# Switch Machine Project



## CliffyJ (Apr 29, 2009)

Hi friends,

I know I have a lot of unfinished projects, but I can't seem to prevent myself from starting a couple more. My apologies for not closing out prior endeavors, but I do intend to complete the switch machine & indication project.

This is related to that.

I've been contemplating an "ultimate" switch machine. Yes, I understand the virtues of pneumatics. Being a specialist in piping systems, I'd favor that. BUT. Given the electrical power available already in a rail-power system (DC or DCC). or almost as easily available as tubing (that is, sprinkler wiring, for an RC or LS layout), I'm interested in an electrical approach.

Furthermore, there are other things that may depend on an accurate reading of point position. Frog power, indication LED's, signal LED's, etc. An electrical approach might be better poised to meet such needs. 

My hope and intent is to develop a switch machine that has the following characteristics.


 Electronics fully sealed against weather and insects
 Works with DCC, DC, or AC
 Prime mover not visible at trackside
 Equipped with electrical contacts reacting to either end of travel, in an isolated hi-amp manner

As a nit, I'd like to add to this list a means of remotely enabling / disabling the indication contacts. This would require...

A wireless means of indication enablement
A dedicated set or indication contacts

I have a design for this, and have parts on order. If anyone's interested, or has a question or remonstration, please chime in.

===>Cliffy


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## fyrekop (Sep 20, 2011)

Cliffy,
Waiting to see what you come up with as I quickly found out that Aristo manual switch throws leave a lot to be desired. Only a dozen switches, plus a few more if sidings find their way in, on my layout so a lot lower requirements from what you are building. Really enjoy watching your "build"
Alan W.


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## riderdan (Jan 2, 2014)

I'm chiming in to say I'm interested.

I think that I'm most interested in point 3: "Prime mover not visible at trackside"

This is what has kept me from moving beyond experimentation with electric switch machines: I just don' t like the sight of that huge box hanging out on the side of the track for all to see. I'm not a rivet counter by any means, but those things tend to be eyesores 

I'd thought about using an under-track system like the Tortise switch motors, but outdoors below track level means below grade which means it would be likely to collect water. Another thought was to place a building trackside with a motor inside and use a long wire the throw the switch from a distance. But I think there would be problems with rigidity unless the building was braced to the track somehow.

Anyway, very interested is seeing what you've come up with.


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## Martan (Feb 4, 2012)

Interesting. I was thinking waterproof servos and wireless control. Pricey though. Latching solenoids perhaps. Like those sprinkler valve ones? Hmm. I 'waterproofed' three cheap servos this fall, they are now buried under a foot of snow, we'll see how they thaw in the spring. I think a little bit of a 'bump' by the track would be ok, prototypical as it could be of course, a bonus would be if it had a signal on it...


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## CliffyJ (Apr 29, 2009)

That's odd, my earlier replies didn't stick. This is a test.


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## SD90WLMT (Feb 16, 2010)

What's that?

..Your test is sticking! !

Sorry 'ol Chap.....


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## Totalwrecker (Feb 26, 2009)

What? No pics?


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## CliffyJ (Apr 29, 2009)

Hi guys, thanks for responding.

The method I propose to use relies on two technical aspects, the viablity of which is tbd.

The first issue, and the main mechanical element, is remote power transmission via translating cable. Specifically, 1/16th inch SS cable thru nylon tubing. Some will call this a "choke cable." Such is able to transmit quite sufficient force, in an undulating path. 

This is the first issue. Pneumatics will have a tube going to a trackside actuator, which will take up a certain transverse volume. A cable-drive, however, will have a tube going to small trackside adapter. 

This second question is the main one, that is, how to push-pull the cable. Yes, we can talk about how to seal the cable, and the glands, and the materials, but that's easy and secondary crap. Once you solve the force transmission, you must next solve the actuator question.

I am going in the direction of a servo, actuated by a driver board. But, all in a sealed housing. I am settling on the Tam Valley board which has numerous control capacities already baked in. 

A big question I have is if their 9G servo can produce sufficient force, when outfitted with a torque arm to produce .3" throw, and with sufficient force. 

I might need to go with a standard-size servo, such as a Hitech HS-311. That would change everything in my design, because of its size. But if needed, so be it.

Here's the basic box, as the design stands.



















There are many details to this, so consider it an overview of something that may or may not work. 

Here is how it would connect with the turnout.










I'll post more, as the prototype progresses. 

Thanks for viewing, best regards, and speak your mind, 
===>CliffyJ


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## Chris Scott (Jan 2, 2008)

If interested if you Google "lever control model trains" you will find a very large number of companies, articles and how to docs on building lever controls for model trains. Here's one example of a freelance model and below is a compalny, MODRATEC, that offers everything you want or need for lever control. In case you're curious about what's out there...


















https://modratec.com/

The MODRATEC Shop where you can buy everything you need for controlling your model railway by mechanical Lever Frame

Either mechanical (wire-in-tube cables) or electronics to your turnouts and or signalling. The Lever Frames are modular and can be made up of from 6 to 60 levers frames, both interlocking and non-interlocking.


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## Beddhist (Dec 17, 2013)

Are you sure you can prevent crud from getting into the switch end of the cable? To my mind a short rod should be more reliable.

However, I would be happy to learn otherwise.


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## riderdan (Jan 2, 2014)

Cliff,

I assume you're thinking that a bowden cable (your stainless line in a nylon tube) fastened at each end would eliminate the need to brace between the actuator and the points? How do you plan to eliminate the free play/take up that results from the space between the line and tube? In my experience (with RC) even over short distances (12~18 inches) there's usually a good bit of play since the tube and cable aren't a perfect fit. Do you plan to compensate by having the servo move the cable more?


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## CliffyJ (Apr 29, 2009)

Chris holy cow. No I'd never seen those before, what fun! Thanks for bringing that company up, I'll be sure to go there and drool like a big dog.

For the down and dirty issues of outdoor op, Beddhist and Riderdan, you've hit the nails right between the eyes.

First, point-end sealing. I was thinking that a close-diameter fit between the cable and tube would be enough. However, some sort of wiper, and/or transition to rod, may be in order. Honestly, I don't know; but I'll try to make an effort in testing the bare cable approach, and see what we see.

Second, diametral play. A close fit would help, but we don't want to add friction. So yes, there will be at least some play. But, the method should rely on some spring force for point alignment, vs. perfectly-programmed hard stops. I was planning on adding a spring at the servo (via a simple kink in the cable, for starters); but for this and other reasons, I'd affirm what Greg E. has suggested, incorporating a spring at the throwbar attachment. 

Another big unknown is how the board works with springs. The servo driver board has an ability to "learn" where to stop servo motion, based somehow on force detection. That's after springs have done their thing. So it will be interesting to monkey with all that.

Thanks guys! 

===>Cliffy


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## CliffyJ (Apr 29, 2009)

Here's the dirty version of servo-side spring. Basically a kink in the cable, with guides from the mount/base that ensures the kink won't foul on other stuff.


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## John J (Dec 29, 2007)

I am doing track inspection today. As do do some repairs I think of things I want to try. ( Pondering) I was thinking of a DC solenoid that would shift either way according to polarity. My other thought was a small Stepper Motor. I was thinking of a stepper motor from a camera lenze used for focus or Iris control. 

JJ.


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## Beddhist (Dec 17, 2013)

Do you think central locking solenoids from cars would work? You may be able to get them cheap from wreckers yards.

Regards,
Peter.


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## CliffyJ (Apr 29, 2009)

Hi JJ & Peter,

I'm not an electrical guy, but what I tend to run into with things like this is the motor controller. So, a good (and cheap) servo and board combo, from the RC hobby direction, makes me feel like it'll work, because it's designed by people who know (vs. me). 

That's not to say that your camera motor idea won't work, but I just wouldn't know how to approach it.

But thanks for your ideas here. Someone in the future may well spot a missed opportunity in what you or others have suggested.

Cliff


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## John J (Dec 29, 2007)

Beddhist said:


> Do you think central locking solenoids from cars would work? You may be able to get them cheap from wreckers yards.
> 
> Regards,
> Peter.



I think you got a workable Idea there Peter. How big are then and can you hide them in your track side Stuff. Maybe put them in a guard shack and run a long piece of Piano wire to the switch.

I like your idea. 

JJ


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## JerryB (Jan 2, 2008)

Why do you want to use a servomotor to operate a turnout?

Since turnouts are simple two position devices (with potentially disastrous consequences of being in any other position), I would think a two position actuator would be much more reliable, easier to design and build, easier to maintain, and less costly.

I use pneumatics and am really happy with the results: Relatively inexpensive, very reliable, virtually 100% weather proof, easily disguised. Since they are inherently watertight, the cylinder can even be located below ground with only a little mechanical protection.

I note that you are proposing to put a spring in the system next to the servomotor. I would think that would introduce another point of failure. In the event the 'linkage' or turnout is jammed, the servo could still think everything is okay. IMO, any spring belongs at the point of connection to the points tie bar. Of course the air pressure set point provides the spring in my pneumatic system.

Happy RRing,

Jerry


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## John J (Dec 29, 2007)

We are Brain Storming here. WE are thinking up ideas and putting them out there. They may not be feasible. Not everything I think of works. Sometimes I have to abandon the project and do something else. 

JJ


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## grsman (Apr 24, 2012)

*Pneumatic controller*



JerryB said:


> I use pneumatics and am really happy with the results: Relatively inexpensive, very reliable, virtually 100% weather proof, easily disguised. Since they are inherently watertight, the cylinder can even be located below ground with only a little mechanical protection.
> 
> Of course the air pressure set point provides the spring in my pneumatic system.
> 
> ...


Jerry
What pneumatic controller do you use for your switches?
Tom


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## CliffyJ (Apr 29, 2009)

Great points, Jerry, and thanks for making them. Let's debate those approaches. 

I think a number of your points deserve underscoring. Yes, air pressure serves as a spring. Yes, if train power is taken off the board (DCC, DC, LS, RC, clockwork...), running a system of pneumatic lines is just as easy as running a system of electrical cable (e.g., multi-wire sprinkler cable).

But. You do have the additional costs of solenoid valves, fittings from them to your actuators, wiring to your valves, and control method for the valves. And, after all that expense, maybe $75 to $150 per turnout by the time you seal everything, you still don't have any electrical contacts for indication or frog power. Further, name one vendor who offers the products, because Ozark, the owners of however you want to spell "easy air", doesn't. All they offer is the cheap fittings, but not the actuators and not the adapters. And not the solenoid valves, nor their enclosures. Nor the boards to drive them. I can buy Clippard and other actuators all day long, but its up to me to design the adapter, pick the SV, and design the electronics interface and housings for everything. It was all way too expensive. So that is why I am looking to a servo approach, with the intent of keeping the solution near $50, and full weather proofing.

I may not achieve this goal. But, I'll try, and take my licks when I fail.

OK Jerry, your turn, blast away. I've given you my best shot, so feel free to return fire.



Cliff


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## Skeeterweazel (Feb 11, 2014)

Sorry for the hyjack, but i'd like to share my switch project. Control switches using phone via bluetooth. Still tweaking it but it works. Think can control 10 switches, limited by outputs on this model Arduino. At this point i'm live steam only. I don't have any DC/DCC. Neat thing w/ the Arduino is that you can program routes to control multiple turnouts w/ one button if needed. Rough costs:
"Knock off" brand Arduino: $10
16 Channel relay board: $18
bluetooth module: $8
air actuator: $24
solenoid : $12 (yet to be tested, coming from China)
air line, resistors: $5
12v power source: hoping to scrounge something up.
air source: tie into compressor or use air pig or ???

Marty


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## CliffyJ (Apr 29, 2009)

That's a great project Mary. I looked into the Arduino at one point, really amazing what it can do, and so cheap. Combined with the relay board, that's great. You can house all your gear (including valves) in a single box even, as long as the tube runs aren't really long. Are you comfortable with the distance limitations on bluetooth? Some folks have raised that as an issue, but I've not tried it.


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## CliffyJ (Apr 29, 2009)

Just a progress shot of my current model, showing the "heavy duty" servo packed in. I also tried to jam in an optional relay board, designed by Tam Valley to plug into the Singlet board. 










The extra 1/4" ID cable glands are for power in, and signal/power out to a frog or indicators. They could be combined.

When the (3d printed) mounting settles down, I'll post a cost estimate.


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## krs (Feb 29, 2008)

I just came across this thread.

Are you guys trying to design something because it doesn't exist or is this just a "fun" project?


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## John J (Dec 29, 2007)

krs said:


> I just came across this thread.
> 
> Are you guys trying to design something because it doesn't exist or is this just a "fun" project?



I am not sure. I have a bunch of Switches and have no Switch Motor for them. I am making my own. I have a couple that may not be accessible so I need a remote way of switching them 

JJ


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## krs (Feb 29, 2008)

Wouldn't it be less of a hassle and probably cheaper in the end to just buy a few?
They seem to run $33.- and change


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## Dan Pierce (Jan 2, 2008)

While a switch machine may be $33 for some, it is the electronics (read DCC) that increases the price.
SO, the EPL drive by LGB needs a decoder to activate it and the all in one units like the Prodrive Cliff uses is less $$$ than buying separate units.

Cheapest is always manual. Even automobile type choke cables can work i manual modes, but not everyone wants manual.
Manual VS electrical is almost like battery vs track power scenarios, it is the end users wants/needs that count.


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## CliffyJ (Apr 29, 2009)

Hi Dan, yep, the ProDrives sure do it all, for $50. They also have the aux lantern contacts, controllable via CV35 (Dan's been working with me on that), almost like an independent decoder for indication or driving a relay. The ProDrive has microswitch contacts ($5 extra), that with CV35-controlled lantern contacts can result in an indication system that can be easily turned on and off (at least, that's what I want). They also have pushbutton inputs (though neither Dan nor I have checked whether those work with the Prodrives under DCC control). 

KRS, compared to the DCC-equipped EPL , the ProDrive cost is far less, the functionality is much higher, and the strength of the servo is better. BTW, you can get the EPL for $30. But for it to be comparable with the Prodrive (with $5 microswitch), add $60 for the decoder and $30 for the aux contacts. So, EPL $120 vs. Prodrive $55.

The controls, ProDrive modifications and indicators has been my main winter project. However, there are weaknesses with my setup. We've had trouble with the CV35 address sticking, but thanks to Dan's help hopefully that will be stable now. The add-on microswitch (which is triggered mechanically by throwbar action) isn't tremendously reliable, or so I've been told. As I said, I'm not sure about local pushbuttons yet. And, the Prodrive isn't sealed: bugs & dirt get in. 

Someone challenged me to find a back-up plan, in case the Prodrives's bells and whistles don't perform in the long term. I'm hoping they do; I sure have a lot of money invested in them. But it would be unwise for me not to have an alternative in mind, that would work with the controls and infrastructure I've designed around the ProDrives. 

So yes, KRS, this has been a for-fun project, though with the intent to build and refine at least one unit. While doing so, I'd like to make improvements. No commercially available switch controller has all the traits I listed at the beginning, e.g., is fully sealed, has local pusbuttons, is operable with DC/DCC/AC, and has high-current aux contacts that reliably switch when the points are at mid-throw. And has a heavy-duty servo. My goal is develop such a device, for around the price of a ProDrive. Not to compete, just to set a ceiling for the project.

The ProDrive still has the ability to remotely activate an indication circuit via CV35 & the lantern contacts. This is lacking in my design; it would require an additional decoder, controlling a relay that feeds an indication power bus. That would push the cost quite a bit higher than the ProDrive, and add the hassle of laying the cable from switch to switch (something I want to avoid). 

Thanks for sharing your thoughts guys.
Cliff


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## krs (Feb 29, 2008)

CliffyJ said:


> So, KRS, this has been a for-fun project, though with the intent to build at least a first article. No commercially available switch controller has the traits I listed at the beginning, e.g., is fully sealed, has local pusbuttons, is operable with DC/DCC/AC, and has high-current aux contacts that reliably switch when the points are at mid-throw. And, now, a heavy-duty servo.
> 
> The ProDrive still has the ability to remotely activate an indication circuit via CV35 & the lantern contacts. This is lacking in my design; it would require an additional decoder, controlling a relay that feeds an indication power bus. That would push the cost quite a bit higher than the ProDrive, and add the hassle of laying the cable from switch to switch (something I want to avoid).
> 
> Cliff


That's what I wanted to get a handle on, Cliff.
You seem to want to design a switch machine that is all things to all people.
Something like that will never be price competitive, but if that is not a requirement,ie this is just a "fun project", that is OK.
My requirements would also include a switch motor that allows the switch to be cut open, the pneunatic ones I have used won't allow that and neither do some electrically driven ones.
The other "must" is true feedback of switch position but without additiona lfeedback wires.
I personally would skip the DCC requirement, but then it wouldn't be universal.

I would think the ProDrive can meet your requirements with a bit of additional work - ie seal the unit and add a local pushbutton.

Knut


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## krs (Feb 29, 2008)

Dan Pierce said:


> While a switch machine may be $33 for some, it is the electronics (read DCC) that increases the price.
> SO, the EPL drive by LGB needs a decoder to activate it and the all in one units like the Prodrive Cliff uses is less $$$ than buying separate units.
> 
> Cheapest is always manual. Even automobile type choke cables can work i manual modes, but not everyone wants manual.
> Manual VS electrical is almost like battery vs track power scenarios, it is the end users wants/needs that count.


Dan,

I agree with you, but why include DCC ?
Only about 15% of Large Scalers in the US use DCC and many of those that I know keep the powering of their turnouts separate from DCC power.

My initial comment in this thread was directed to John - all I meant to say is that buying a commercial switch drive is a lot cheaper and probably more reliable than trying to build your own, manual remote ones probably excepted.

Knut


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## CliffyJ (Apr 29, 2009)

Almost done with the packaging, and about to get a trial run of the printed parts.



















The big thing lacking still is a throwbar spring, so that's next to investigate.


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## CliffyJ (Apr 29, 2009)

About throwbar springs, and a good point that Greg raised elsewhere, that the train should be able to cut the switch points. I've been designing around switch machines that don't permit that, but it would be wonderful to have that ability. 

I'll be looking for tightly-packaged examples of springs between the throwbar and air actuators or ground throws, and if someone has a favorite approach for that, I'd love to see it.


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## krs (Feb 29, 2008)

Cliff,

If you're going allow operation where the turnout points are cut open AND if you allow for powered frogs, assuming you use some type of track power, you now need to somehow prevent a short in those cases.

Knut


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## toddalin (Jan 4, 2008)

CliffyJ said:


> About throwbar springs, and a good point that Greg raised elsewhere, that the train should be able to cut the switch points. I've been designing around switch machines that don't permit that, but it would be wonderful to have that ability.
> 
> I'll be looking for tightly-packaged examples of springs between the throwbar and air actuators or ground throws, and if someone has a favorite approach for that, I'd love to see it.



The "kinks" that you put in your bar should already accomodate this if the wire is springy.


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## CliffyJ (Apr 29, 2009)

Hi Todd, always great to hear from you. Yes, I agree, if things are clean. But if dirt gets in the tube, or if the run is long, the resistance might be too much for regular cars to push the points over. The servo would do its job, and the cable kink would protect it from whatever lockup might occur. But for point cutting, with every wheel trying to rattle their way through, I'm not as confident. 

Your thoughts?


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## CliffyJ (Apr 29, 2009)

krs said:


> Cliff,
> 
> If you're going allow operation where the turnout points are cut open AND if you allow for powered frogs, assuming you use some type of track power, you now need to somehow prevent a short in those cases.
> 
> Knut


Thanks Knut. I've not worked with point-cutting switch machines, and some or most of my switches do (or will) have passively-powered frogs (via throwbar reed switch). So that sounds like an incompatible scenario, as I believe you are saying. 

Hmmm, more food for thought. Thanks very much for pointing that out Knut.

[edit] I'm using DCC, and maybe that does or does not obviate that issue. Don't know. But for a DC rail-power system, I'd think the issue stands. I'll rely on the experience of you and others to address that.


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## SD90WLMT (Feb 16, 2010)

Typically what is refered to here as kinks...are really a means of fine tuning the rod length...and resulting position of whatever may be on the receiving end.....think end point adjustment...

So...unless the wire is very small and flexible..I have a hard time seeing it give enough for cars ..even lite weight cars... being able to cut the points. .

And if the wire is that light .... will it perform.the intended task?


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## toddalin (Jan 4, 2008)

Piano wire is very strong, yet very springy. I'd first try it as drawn.

If that's not working for you, try putting another set of "kinks" out by the throw bar in the horizontal plane.


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## SD90WLMT (Feb 16, 2010)

As I have my plate full of experiments currently Todd, I'll gladly differ to you.

I have used and played with music wire for 20 some years in model airplanes..
..from 1/4" landing gear legs down to 1/64" throttle linkages...

I think you first need to test how much effort our lightweight train cars can exert and push points out of their way.
1/16" wire with a "Z" or "M" bend will not move for this purpose...
1/32" wire is still pretty stiff
Going down to 1/64", that's only 0.015" thick..& may not give much either!!
The smallest piano wire made is 0.006" thick..

Please have fun experimenting...let us know!


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## toddalin (Jan 4, 2008)

OK then, use spring wire.


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## wigginsn (Jan 9, 2008)

From my experience using choke cables for turnout throw, the gap between the case and the 'piano' wire allows some movement before the mechanical thrust is available at the end point.

Perhaps this would be sufficient to allow the points to be pushed open? Just 'nother 2c input.

Great experiment Cliff by the way..

Cheers
Neil


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## Skeeterweazel (Feb 11, 2014)

CliffyJ said:


> ... that the train should be able to cut the switch points. I've been designing around switch machines that don't permit that, but it would be wonderful to have that ability.
> .


Being able to cut would be useful in case the switch is in the wrong position? Just as a "safety"?
thx.
Marty


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## Chris Scott (Jan 2, 2008)

Cliff,
How about a multi-channel servo controller using USB communication/connectivity? They seem to come with a simple computer program to configure each servo, (range of motion, etc.) Not saying use a computer interface to actually operate the servos real time. Maybe an array of toggle switches on a layout diagram, or something. Quick Google search found lots. Controllers from 1 to 24+ channel controllers. They seem cheap - 24 channel controller $50. Seems to me putting the servo at the switch directly connected to the switch control arm is the most obvious and simplest approach. A box with the servo can be coated with spray-on rubber sealant so it's impervious to the elements. 

Two examples; Google search terms; "servo controller"
Robot Shop; Servo Controllers; http://www.robotshop.com/en/servo-controllers.html
Pololu Robotics and Electronics; Motion Control Modules; https://www.pololu.com/category/9/motion-control-modules


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## CliffyJ (Apr 29, 2009)

Thanks for all your suggestions guys. 

Dirk, you mentioned whether it would defeat the purpose to have a really springy spring at the points. That, and Knut's point about frog-shorting while switch-cutting, are new new logic puzzles that I've never had to consider before.... and I don't know the answers. I should probably rip out a switch that has a reed switch powered frog, and experiment with it. 

Like you say Marty, it would be a useful safety feature, especially for the sake of not derailing an expensive loco. So I'd like to push this feature a bit more, and see how the other problems do or don't settle. 

Chris, all great ideas. I'm using the Pololu Meastro on a different project (in a non-R/C version), and it's an amazing product for its price. Something like those from Robotshop, which have the built-in receiver, would be great for a non-rail-power application, which is something I'd like to attempt after putting this (DC/DCC) one to bed. 

Thanks Dirk, Neil and Todd guys for your thoughts on what sort of wire to use. I should clarify something about the cable I'm currently designing for. My vague hope was to make this switch machine strong enough to permit longer cable runs (to hide the box, maybe co-locate a few under a convenient fake rock, and still ensure a proper amount of force at the throw bar. The kink inside the box is for servo protection, and the cable is 1/16th ss wire rope. So, pretty rugged. 

Now, it sounds like you're also adding the idea of a single wire running through the nylon tube. The might be nice, because end-kinks would be true springs; and maybe no further hardware would be needed. Might be more subject to accidental kinking than the 1/16th rope; might not. Don't know. Seems like a perfectly valid way to do it though.

As for the spring at the throwbar, I've seen a number of approaches. Some are a simple in-line spring, traveling with and between the mover and throwbar. The ProDrive internal springs are like that. Some are trickier, with an over-center flip-flop spring, like the one inside the Aristo machine. The former seems more straightforward; the latter more difficult to apply. 

Since force at the throwbar is related, I'll make a further confession. I'm also working on a switch stand project, which is located on the opp side of the cable connection. The throwbar force would need to move that as well, and that might be too much for a switch-cutting spring. I don't want to muddy the waters with that now, but I'm in favor of a switch-cutting approach that still has oomph. 

Thanks again guys,
Cliff


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## krs (Feb 29, 2008)

As to cutting the switch open....
In the prototype there are very few turnouts that are designed to be cut open.
I ever only saw a video of two of those - but it was neat to watch the turnout points moving automatically after the loco had passed through the turnout thrown the wrong way.
For model trains there are three choices
1. Not allow the turnout to be cut open. If it's not set right the train derails. Pretty much standard prototype operation and I think this will happen with the ProDrive; I know it happens with the air-powered ones we're using on one layout
2. Allow the turnout to be cut open and when the train has passed, the points will still be in the original position. Great to prevent derailments for sloppy operators but it doesn't reflect prototype operation. The LGB switch motor with a manual throw will do that.
3. Allow the turnout to be cut open and when the train has passed, the points will have moved to the opposite position and stay there. Also great to prevent derailments for sloppy operators. The electric LGB switch motor will do that.

So the decision would have to be made - which type of operation does one want?


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## CliffyJ (Apr 29, 2009)

The prototypical question is another great point to consider, thanks for raising it Knut. 

For me, I've been planning all along for non-cutting switches, because that's how the ProDrives work. So I'm fine with remaining in that direction.

I've also used Aristo and LGB manual drives some, and saw that they allowed cutting. So I've been unclear on what an "ideal" product should have. I suppose if one were designing for mass market, one would clearly include the cutting feature. 

If there were some way to allow the cable connection to be either sprung or unsprung, and let the user decide, I suppose that would be the ideal. 

Dirk raised a point in a PM, that I think is very applicable: if you allow switch cutting, and your lightest car can't move the points, it's useless. My lightest cars are 4-wheeled lightweight ore cars. I don't want to weight them down just for switch cutting (though I will some, for stability). 

So for me, your option #2 would be a no-go, for car weight and the frog-shorting potential. 

As Marty pointed out, it's still a nice insurance policy. Your #3 might be the best though. The philosophy would be that if a loco pushes the door open, it should stay open. And if the operator forgets that and doesn't like where the points end up, well, you can't have everything. Sounds like it would require sensors & etc. though, and not really part of the switch machine. Unless you've seem such a mechanism that you can share?

In summary, my operation is #1, though #3 would be nice. Others might want #2.

Cliff


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## CliffyJ (Apr 29, 2009)

Here's a thought, based on this design.

http://lsc.cvsry.com/Post2/SwitchPin001-800.jpg
http://lsc.cvsry.com/Post2/SwitchPin002-800.jpg
http://lsc.cvsry.com/Post2/SwitchPin003-800.jpg

It looks like an over-center spring that holds the points lightly to one side, but will flip over when something presses the other way. It reminds me of TW John's spring, though that was a longer straight wire, as I recall (?). 

Anyway, I don't know if a loco would flip this thing over, or if a stick is needed. But here's the idea. The fixed end of the spring would attach not to a fixed tie, but a moving throwbar thrown by the switch machine. It's perhaps analogous to how the internal Aristo spring works. So the machine would make the points go one way; but a cutting loco could flip them the opposite way. 

Sounds VERY tricky though to make the geometry and spring and throw forces work. Maybe I'll put this off till later as an optional add-on thing, because my brain is starting to hurt...


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## SD90WLMT (Feb 16, 2010)

So get out doors and "prove it"[email protected]@

A practical demonstration of a theory ...put to the test...


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## CliffyJ (Apr 29, 2009)

Sure Dirk, I'll test the design. Need to make the parts first though, which requires a design. 

To that end, I'm going to down-scope this current project, and refocus for the moment on the switch machine and direct throwbar linkage, sans throwbar spring. I've been doing some what-if's for the latter, and it is proving too elusive for me to tackle in this effort. Not to discount such adjunct features, those are important too. And feel free to continue discussing anything you care about on this thread, as long as it's related to switch drives. Everyone's been contributing excellent and related points that belong in the stew pot, and I sure don't want to stop that.

For myself though, I'd like to make a first-article switch machine per the last posted pics, with the following caveat: replace the cable kink and crank-disk with a "servo saver," as some have suggested on the sister thread on LSC. This would be a more repeatable and professional feature to, literally, save the servo. Also. it would allow a much easier release of the box for repair/replacement. I'm still trying to pick one out, because the shaft diameters & spline details need to match the servo. Once I do, I'll update the model and post a pic.

One other nagging thing is the electrical cable. Though glands are shown for that, it would be really nice to have something easily disconnectable. I have a wp connector that might do the job, but again, it adds cost.

[edit] 
Strike that last. The various conductors aren't going to the same place, so a nice and expensive multi-con w/p connector is wasted. Two wires are for incoming power (DC, DCC, AC). Other (optional) wires are for signal/indication out. Another two wires are for a local pushbutton in. And maybe a different power source input for indication. So... rather than an all-in-one connector (which would immediately split to different destinations), the gland is ok, with multi-con sprinkler wire going thru. BUT, outside the gland would be different connectors per the different destinations. For example, I like, and have used, the EC5 2-prong connectors and Dean's plugs from http://viciousteknology.com/connectors1.html.


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## CliffyJ (Apr 29, 2009)

Yes, the ProDrive is an excellent bargain. It's the only drive I have on my layout. I think I can fairly cite it as my inspiration for an "ultimate" outdoor, all-climate, all-control philosophy switch machine. 

So, for the sake of design discussion, why not pool our thoughts, and consider what might be possible? In healthier industries, ideas such as what you just wrote would be taken into consideration for further versions. But in our hobby, which no longer benefits from the most robust manufacturing support, we have to talk amongst ourselves and try to move the state of the art forward as best we can, even though in small increments, and even if on an amateur basis. 

As my design stands, I don't think the cost would be outrageous. Here's where my present hard costs breakdown is standing for a "hardened" switch machine.


Basic machine, with a $5 servo saver and 4' of drive cable: $60
For comparison: the ProDrives I use list at $50, and are a true bargain I think.
Note that $19 of my cost is just for the 3d printed mount. If cast from resin, maybe $10 would be taken off.
Basic machine upgraded for relay (for indication or frog or whatever): $68 
 
This cost estimate doesn't include the extra functionality that the ProDrive machine has in enabling a set of indication contacts via DCC. It's hard to calculate a per-machine cost for that, because it would be a system-wide thing, shared by all the turnouts. But, call it $10/per.

No, my costs don't include profit, or even shipping. And assembly labor. But they also don't include the benefits of design-cost reduction, bulk purchasing, and large scale production. In other words, whatever the state of the art could or should be, it's not on a different price planet than EPL, or even ProDrive. 

Speaking of which, let's compare all this again to the LGB EPL:

Basic machine: $30
Decoder add-on: $60
Aux contacts add-on: $30 
Total: $120
 
I'll bet that for that kind of money, an "ultimate" switch machine could be on the commercial market that would satisfy most folks. And it would be amenable to all kinds of layouts, not just rail-powered.

For that inferior EPL assembly, it would be hard for me to put down that kind of money, and leave these sensitive devices outside over the winter. My Prodrives though went through last year's weather just fine, and have done for others over many years. And they have such great features.

Why try to improve on the ProDrive? Heavy-duty weather-sealing, heavy-duty indication contacts, better interface for local pushbuttons, more flexibility in control schemes, and the ability to remotely locate the drives. Also, because it's a fun design project. 

Having said all that, I truly appreciate Train-Li, and I consider the Tillmann's and Dan Pierce friends. They've helped me hugely in the hobby, on a personal basis. And don't get me started on their nickle-plated brass track, it's OUTSTANDING for so many reasons. But, I want a backup plan, in case the ProDrive's have issues in the long run. 

All I'm doing here is making a first article, and engaging the ideas of yourself and others, in the hope of moving the design football forward. But I'm still using ProDrives, and am ordering more as we speak.

Thanks Knut,
===>Cliffy


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## mickey (Jan 28, 2009)

So I first got the LGB switch machines. I'm running LocoLink which is RC with constant 18v DC on track. They seem to work and have been out for a year now in Central Texas heat, rain and cold including several freezes with no issues yet. But I would like some visual direction indicator so ordered one of the LGB addons at $14 to test and while it works, it looks funky (probably a German RR thing) and is just same color light regardless of direction. From distance hard to tell the symbols too. So for someone who doesn't plan to go the DCC route, what advantage are the ProDrives at $50 over the LGB at $25.


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## Dan Pierce (Jan 2, 2008)

Prodrives have a DCC decoder built in, address 0 makes them DC drives, but writing an address in CV 1 makes them DCC. 
Once you give them an address, a track powered DCC system only needs the prodrive wired to the track for operation.

Also, LGB drives (12010) are $30 or more for new ones.


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## krs (Feb 29, 2008)

mickey said:


> So I first got the LGB switch machines. I'm running LocoLink which is RC with constant 18v DC on track. They seem to work and have been out for a year now in Central Texas heat, rain and cold including several freezes with no issues yet. But I would like some visual direction indicator so ordered one of the LGB addons at $14 to test and while it works, it looks funky (probably a German RR thing) and is just same color light regardless of direction. From distance hard to tell the symbols too. So for someone who doesn't plan to go the DCC route, what advantage are the ProDrives at $50 over the LGB at $25.


Mickey,

As you assumed, the switch lantern is a German RR "thing" - it's actually pretty close to the prototype.
You can also buy a "Swiss type" switch lantern that will fit on the drive.

However, both laterns rotate by 90 degrees adding a bit of resistance when the turnout is activayed - if you have long wire runs or low voltage that may just make the difference between a solid throw and a marginal one.

Electric switches of North-American railroads, at least the ones in Canada I remember seeing, don't have any switch lanterns or equivalents - I only see indicators for manually operated switches.

Would be neat if somebody came up with something for US/Canada that would mount where the LGB switch lantern normally mounts so that one can easily see the switch position from a distance.

Knut


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## CliffyJ (Apr 29, 2009)

krs said:


> Mickey,
> 
> Would be neat if somebody came up with something for US/Canada that would mount where the LGB switch lantern normally mounts so that one can easily see the switch position from a distance.
> 
> Knut


Since you guys brought it up, here's where I'm heading. I'll go into it more, once my first-article switch drive is working. But as an overview, this is an indicating (not controlling) switch stand, mounted to the opposite side of the drive. It could be various versions of harp or rotary, with easily swappable targets.



















It has electrical contacts for aux functions, such as (again) indication or frog powering. I'm testing different magnets for the reed switches. 










Here's a section showing the basic magnet / reed / throwbar interaction. I'm using 2 reed switches, which can be SPST or SPDT. I'll probably pot them in with silicone, and just have terminated leads hanging out. 










A variant I'd like to try has a magnetic coupling in the throwbar, so that the stand can be used as an actual switch. For example, sending a command to the drive to flip. Once that move happens, the magnet re-registers, and the stand serves once more as an indication device. 










This design isn't complete, obviously. But feel free to comment!

===>Cliffy


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## toddalin (Jan 4, 2008)

The reed switches won't stand up to the current that could be drawn through the frogs..., for long. You could use them to trip a relay.


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## CliffyJ (Apr 29, 2009)

Good point Todd. I'll quite mentioning frogs, haha!


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## Skeeterweazel (Feb 11, 2014)

Cool! How soon till you can make me one? Ha!


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## CliffyJ (Apr 29, 2009)

Thanks for the vote of confidence Marty


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## mickey (Jan 28, 2009)

The visual indicator is what I was thinking. I'm even considering trying to a green film on one side and red on the other to get the LGB to at least give a color I could see from distance. As for price, I was recently told that LGB lowered the price a little so could get for $25 on street. Haven't tried to order yet, though


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## CliffyJ (Apr 29, 2009)

Mickey, consider yourself in good company, because I've heard that many experiments were done on the targets to best see throw direction at a distance. The V&T ended up with the big red dot over the small green dot, but different RR's came up with their own preferences.

The LGB stand is probably based on the Euro / RhB designs, right? 

BTW, here's one from Train Li, lighted, 
http://www.trainli.com/bproline-customb-dbdr-switch-stand-left-p-5904.html

And a beaut from Sunset Valley, non-lighted, for only $25, in brass! 
http://www.sunsetvalleyrailroad.com/switches.html

Off topic, but I just noticed this relevant 2009 thread by RJD, and wow, all the pics are working!
http://forums.mylargescale.com/24-product-reviews/7527-train-li-45-switch.html

From that, I saw that Ozark has a stand too.


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## CliffyJ (Apr 29, 2009)

toddalin said:


> The reed switches won't stand up to the current that could be drawn through the frogs..., for long. You could use them to trip a relay.


After checking the specs, yeah, only 500ma max current. Huh, I was expecting more, but thanks again for the catch Todd.


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## krs (Feb 29, 2008)

CliffyJ said:


> After checking the specs, yeah, only 500ma max current. Huh, I was expecting more, but thanks again for the catch Todd.


Not sure what you want the reed switch for but you can readily get them up to a rated 3 amps switching current.
Those tend to be larger, more expensive and less sensitive than the lower current ones.
These would typically carry 5 to 6 amps.

Knut


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## krs (Feb 29, 2008)

mickey said:


> The visual indicator is what I was thinking. I'm even considering trying to a green film on one side and red on the other to get the LGB to at least give a color I could see from distance. As for price, I was recently told that LGB lowered the price a little so could get for $25 on street. Haven't tried to order yet, though


What do visual indicators on electric switches of US railroads look like?
I can't recall ever seeing any on Canadian railroads.
Tried google and came up empty - all they had were either switch stands for manula switches or the contraption that Aristocraft uses which look like caboose lanterns mounted on an electrical switch.

Also came across an article how to modify an LGB caboose lantern to fit onto an LGB electrical switch drive - but is that anything even close to the prototype?


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## riderdan (Jan 2, 2014)

CliffyJ said:


> The LGB stand is probably based on the Euro / RhB designs, right?


Yep: http://upload.wikimedia.org/wikipedia/commons/e/e3/Mh_eisenbahnweiche_mit_handhebel.jpeg

I really like the Ozark harp stands, even though they don't exactly "go" with what I'm modeling. I think that having the marker "lean" towards the diverging track when the switch is set that way is clearer than most other indicators I've seen. This is why I'm leaning towards using them as indicators (only) when I get around to adding motorized switches to my layout.


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## krs (Feb 29, 2008)

For an electrical switch the switch lantern actually has an arrow pretty close to the LGB model.


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## toddalin (Jan 4, 2008)

krs said:


> For an electrical switch the switch lantern actually has an arrow pretty close to the LGB model.



Agreed that this would be the prototype for the LGB version.


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## Greg Elmassian (Jan 3, 2008)

Don't forget that reed switches are normally specified for a non-inductive load, steady DC... that is not what is happening with a locomotive. You really need to have them set up to handle a dead short in terms of current.

Just not a great idea unless you are running very low current locos AND have a fast acting circuit breaker (solid state) AND a limited amount of current under a short.

I don't think you have even one of the 3 above Cliff.

Greg


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## CliffyJ (Apr 29, 2009)

For the reed switches, I was mainly thinking (for my application) about powering LED's or commanding a switch drive. I shouldn't have mentioned frog powering. Still, I think it would be nice (in theory) to have a switch stand that had reasonably decent switch contacts. But the reeds I have aren't it.


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## toddalin (Jan 4, 2008)

CliffyJ said:


> For the reed switches, I was mainly thinking (for my application) about powering LED's or commanding a switch drive. I shouldn't have mentioned frog powering. Still, I think it would be nice (in theory) to have a switch stand that had reasonably decent switch contacts. But the reeds I have aren't it.


OK, I don't understand.

If you can have the other parts that hold and move the reed switch or magnet made on a 3d printer (or by whatever method you intend), why can't this same/similar situation be used just push two pieces of brass/copper together to make a contact (think modified knife switch)?

That could stand any current you would throw at it with no expense of delicate reed switches.


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## krs (Feb 29, 2008)

Cliff,

You need to decide on the application where you want to use the switch or control first and then select the appropriate switch.
A reed switch is usually used if you want something activated by an external magnet.

Knut


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## Greg Elmassian (Jan 3, 2008)

What he said 



toddalin said:


> OK, I don't understand.
> 
> If you can have the other parts that hold and move the reed switch or magnet made on a 3d printer (or by whatever method you intend), why can't this same/similar situation be used just push two pieces of brass/copper together to make a contact (think modified knife switch)?
> 
> That could stand any current you would throw at it with no expense of delicate reed switches.


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## CliffyJ (Apr 29, 2009)

Great point Todd. The attraction to reed's for me thus far was their being sealed and rated. I considered them without looking into their capacity; I'm pretty embarrassed! But wiring them to a solid state relay kicks the cost of this theoretical product out the roof. So yes, designing in actual contacts from scratch makes sense -- as long as they can be kept clean and worry-free. 

I'd also like to understand what happens with selling something like that, in view of the electrical ratings. For example, there are contacts beneath my turnout points that act like a switch, because they ensure power to the point rails. They're sure not UL approved. But if you make your own contacts and tell a buyer that they're available for unspecified electrical use, you have to give a rating, or at least limits.... Maybe if it's 12v or 24v, it's below the radar, so to speak. I have no idea. 

Not that I'm going to sell them, or at least in the foreseeable future. In my retirement years though, I might like to for grins, as part of my hobby. It would be a fun sort of thing to develop and peddle, if no one else does. For example, though there's no money in it, it would be fun to research and model up different kinds of targets, stands, and lanterns.

Knut, I apologize for being confusing. I'm going to make some of the (harp) switch stands for a mechanical indication, and because the V&T used them. It'll take a while to work out the bugs just for that. Personally, I don't have a particular electrical need for these, except for them acting perhaps as a local switch to command the adjacent turnout drive. And maybe some LED-based signalling, not sure. But I thought it would be cool to make the design generically useful, while I was at it. That's the for-fun / puzzle part. 

Cliff


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## Greg Elmassian (Jan 3, 2008)

Cliff, what about a microswitch inside? I know you can get 5 amp ones.

they also have sealed ones, but you might not need that level.

Greg


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## toddalin (Jan 4, 2008)

Just seems like it would be so easy to put a brass tube over the lower end of the lower end of the harp stand and have it toggle between to brass "C"s.


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## CliffyJ (Apr 29, 2009)

Great ideas guys. Todd, I was looking at something like that, except with a slider plate (which is common to both the rotary and harp designs) that alternatingly touched 2 out of 3 brass contacts. Would be the cheapest approach, I expect.

Greg, you're right, and here's a Cadillac version: sealed, 10A... really nice.
http://www.mouser.com/ProductDetail...ha2pyFadug%2bfGHS9ncW7kqJ3ezvEzz8ztcJdJiB1uM=

Also need to deal with the screw terminals I suppose. It would be neat if there were a 3P terminal block facing down, where a wiper could slide across the upper (normally bottom) side, connecting 2 of 3 of the contacts. 

Back to the drive. I'm supposed to get the servo saver in today, which would allow me to finish up the model.The connection to the saver is still hopefully with the Dubro EZ, but we'll see. After the Dubro comes a piece of brass rod and a wire clamp (cut out of a nylon terminal block). It bites down nicely onto the wire rope.










Also supposed to get the box today. It has a clear lid to be able to see the LED status lights, and otherwise monitor things. Not sure if I mentioned it, but the LED's are bi-color. From the Tam Valley web site: 

Bi-Color LEDs - Gives you full control of the indication color for each track. Each LED can be set to one of 4 colors - red, green, yellow (red and green on simultaneously) and dark(off) for each position. For example you can indicate the open track with green and the closed track with red, or you could use green/yellow, or you can have the open track be green and the closed track be dark.​
The board also works with a remote button, which I've shown at the end of the box. You press it once to alternate the throw.

===>Cliffy


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## grsman (Apr 24, 2012)

This guy seems to have drive and switch stand indicator.
  
  

This looks like brute force, but it appears to work.
Tom


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## Chris Scott (Jan 2, 2008)

Cliff;
Your dedication to this project is truly amazing !


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## CliffyJ (Apr 29, 2009)

Thanks Chris, I sure appreciate the encouragement!

Yeah Tom, I think those are the SVRR stands. Aren't they beautiful? I saw them mentioned on another thread (and posted on it a little earlier), so I had to get one. Especially for a solid brass machined product, their price is very reasonable I thought.


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## CliffyJ (Apr 29, 2009)

I tested the board today, and guess what? Everything worked perfectly, and I didn't smoke anything! Thanks again to Greg E. for pointing me to Tam Valley, this system is pretty amazing. 

Here's the test setup:










Starting at top and working clockwise:

1. Power in (in my case, DCC; but it can be DC or AC, though I've not gone into that).
2. Relay, in this case DPDT 2A (they have an SPDT 10A available, and I need to make sure that fits in the box...). 
3. Servo. This is the heavier duty Hitec HS-311 that TV recommends for this board.
4. Local button. Press once, the servo goes to the opposite side. I used a JST female battery-type plug to connect.

The DCC address was simple to program. And seeing the indicator lights do their thing is very cool. It was also great to verify that the servo operated via 3 command opportunities: the pair of on-board buttons, the single local button, and the DCC handheld.

The auto-align thing is really neat. When in that mode, the servo slowly hunts in one direction until it meets hard resistance, then backs off a hair, and the board remembers that position. Then it does the opposite. In this simple test setup, and by using my fingers as the "hard stop," it worked like a champ.

===>Cliffy


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## CliffyJ (Apr 29, 2009)

One more thing, about that Dubro EZ connector. I added the 2-screw wire clamp to allow release the cable easily, via a vertical screw or hex driver, because the Dubro screw isn't accessible (thanks to John C. from LSC for pointing out that issue). But now that the clamp is there, I've been wanting to can the Dubro. 

So, I drilled a hole in the clamp at right angle to its axis. It was easy, because the clamp turned out to be plated brass. I clipped and inserted a brass nail, and voila:










Need a cleaner nail and a couple washers, but it looks workable. And, it will accommodate the thicker tab of the servo saver. 

===>Cliffy


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## Totalwrecker (Feb 26, 2009)

CJ,
Wrong clamp.
JC


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## CliffyJ (Apr 29, 2009)

Feel free to explain, Brother John. 

An issue has surfaced with the servo saver. Its spring is so stiff that any forced rotation just back-drives the servo; it seems designed to only remove transients sharp enough to break a servo tooth. I was expecting something far springier, to allow at least some point movement without motor backdriving. So I replaced the spring and now there is around 1/4" of sprung saver rotation (either way from center) before the motor backdrives. That's greater than the point movement, so I guess that's ok. This might change in a couple weeks though, when the printed parts come in and the components are assembled to a turnout for real testing.


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## Totalwrecker (Feb 26, 2009)

Well your box illustration didn't show a cable, but I think a metal Swing Keeper would hold the cable as well, if you bent the end with needle nose pliers. 
I'm wondering if solder would hold the ends together....
JC


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## CliffyJ (Apr 29, 2009)

Yep, another gentleman on LSC pointed that out the swing keeper (I didn't know what it was called), but as you're saying, the cable might not behave well with a sharp 90 bend. Also, I'm wanting to be able to release the cable from either end and maybe feed it back through the tube, so it needs to be just a cut cable end (hence the "clamp").


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## CliffyJ (Apr 29, 2009)

I just ordered the printed parts, so I guess the build will be on hold for a couple weeks until they arrive. Here's the bits:










What I'm messing with has a lot of shortcomings, and there are many other ways to skin this cat. So please feel free to share your views & ideas on what you think a switch drive should be, and keep the conversation going.

Thanks for viewing,
Cliff


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## Totalwrecker (Feb 26, 2009)

Do you envision sharp bends and long runs?
I know spring wire will behave better than cable when it comes to push. I have seen cables spiral inside the housing (old choke cables after the return spring broke) rather than staying straight like highly tempered steel wire. 18 ga wire will be plenty stiff....
It can easily be released, not pulled out both ways, but an easy make/break is the selling point. Use that clamp on the other end...

Sorry I joined this conversation so tardy.
I hear your reasoning, but, too much here.... I wouldn't dare make an electrical suggestion. 
Pssst that other guy? Me.
JC


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## CliffyJ (Apr 29, 2009)

Totalwrecker said:


> Do you envision sharp bends and long runs?
> I know spring wire will behave better than cable when it comes to push. I have seen cables spiral inside the housing (old choke cables after the return spring broke) rather than staying straight like highly tempered steel wire. 18 ga wire will be plenty stiff....
> It can easily be released, not pulled out both ways, but an easy make/break is the selling point. Use that clamp on the other end...
> 
> ...


HAHA! Wow, you sure got me that time John! 

Sure, there are pro's and con's to single wire and cable, and I can only guess what might be best in a generic situation. 

For me, I'm not expecting sharp bends, but I do want to locate the drives "flexibly," that is, park them somewhere simple for starters, but relocate them to a "building of opportunity" down the road. Also, there would be elevation changes, no matter what.

Other than that, if the design is useful for someone else, I'd say either one: wire or cable, whatever's best. Especially if there's a reasonably straight shot to the throw bar, and not a whole lot of chance to kink it, by all means use rod or wire. 

OK, I need to bag this project and plot my revenge...



===>Cliffy


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## Totalwrecker (Feb 26, 2009)

One pic after Chemo, one pic before... 2 peoples.
The beauty of spring wire is it wants to remain straight as we make it bend. Using pliers to make a sharp bend over rides the spring and forges a new shape; the bend. Anything less will resist and 'spring back' to tangent.
It will snake around just fine in a sheath or cable housing.
I want you happy, not me. 
John C


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## CliffyJ (Apr 29, 2009)

OK, you convinced me. Let's test both!


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## Totalwrecker (Feb 26, 2009)

I think you'll be pleased.
John


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## CliffyJ (Apr 29, 2009)

Since I'm waiting on parts for the switch drive, I'm looking at the switch stand again, but starting over with the electrical contacts as the priority. 



Greg Elmassian said:


> Cliff, what about a microswitch inside? I know you can get 5 amp ones.
> 
> they also have sealed ones, but you might not need that level.
> 
> Greg


Greg, I was about to integrate a microswitch, and found that they have very different ratings for DC current vs. AC. Like, 1A DC vs. 10A AC. Now I see that the sealed cherry switch (that I pointed out earlier) doesn't list a DC rating, and their 10A is specifically for AC. I just emailed Cherry for DC rating data...

Questions: 
- Why the dif?
- For component ratings like this, does DCC act more like AC, or DC?
- For frog power, where multiple wheels are in contact and only 1 wheel at a time is on the frog, and the total current for all wheels is 10A (DC / DCC), what should a frog-powering switch really be rated at? 5A DC? 1A DC? 

I'm also looking at home-grown contacts, as Todd suggested.

===>Cliffy


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## krs (Feb 29, 2008)

Cliff,

here is a bit of information on that:

Page 6 - Electrical Conditions
*http://tinyurl.com/ob5wwb3*

I would look at the DC rating if you want to make that switch control as universal as possible.

Knut

PS - links don't work, copy and paste didn't work and uploading the pdf didn't work either - pdf file is too big for this forum to handle.
Cliff - don't worry why there is a big difference between AC and DC current handling - there are valid technical reasons.
Just see if you can find an inexpensive one with a suitable DC current rating.


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## CliffyJ (Apr 29, 2009)

That sure has a lot of info Knut, and I just saw this,

Be sure to check both the AC and DC ratings of the
Switch by referring to its datasheet. The control capacity will drop
drastically if it is a DC load. This is because a DC load, unlike an AC
load, has no current zero cross point. Therefore, if an arc is generated,
it may continue for a comparatively long time. Furthermore, the
current direction is always the same, which results in contact relocation
phenomena, and the contacts hold each other with ease and will
not separate if the surfaces of the contacts are uneven.​
Very informative. So yes, I agree, stick with DC ratings!! 

Thanks very much,
Cliff

PS, I was redirected to here:
http://www.digikey.ca/Web Export/Su...snap-action-switch-tech-info.pdf?redirected=1


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## CliffyJ (Apr 29, 2009)

While I'm waiting for Shapeways parts, here's a small update on related matters.

Based on the comments received, I've re-booted the switch stand design and started around just the contacts. Off-the-shelf 5-10A adaptable switches are elusive and pricey. However, Todd B. and Greg E. encouraged me to consider going homegrown, so I've taken their advice. 

Long ways to go, but here is how things are shaping up. This is a bottom view, showing DPDT contacts of 1/16 x 1/4 bar, held down by "printed" keepers and secured with the same screws that would clamp the wire. 










The wiper is the same material, sprung against the contacts with two 1/8" SS springs. The thickness of the wiper keeps it in its pocket, though bent-down ends would insure it.










The orange-ish block is the wiper carrier, and also the thing that the rotary or harp switch stand would be thrown by. I've not yet put in the throw bar that would move it, but I'm leaning toward bent 1/8" rod that could be trimmed to suit. 

Since a switch drive might not have a lot of excess force to move the carrier (and the stand with it), low mechanical resistance is good. That's why I went with springs, which can be altered to repeatably achieve a specific force, vs. bent brass bars which might be more subject to inconsistency. At least that's what I'm comfortable starting with.

The connecting ties are sized for a 4" harp stand clearance. The ties would be trimmable, if one wanted to reduce this clearance. The six contacts hold down the carrier and retain the wiper. At least that's my story, and I'll stick to it right up until assembly day. 

Speaking of switch drives, I received the box a couple days ago. Here's how it sizes up with, from left to right, the Aristo,ProDrive, and Piko (& LGB) machines. 



















Thanks for viewing,

===>Cliffy


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## toddalin (Jan 4, 2008)

Very nice. Be sure that the brass is laid out in a "break before make" fashion so that you don't end up with a short circuit if you are switching polarity.

In the picture, your throw bar looks a bit long, like it could span the center and touch the two outter contacts simultaneously, and I don't think that is what you are after here, though appropriate in some situations.


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## CliffyJ (Apr 29, 2009)

Good eye, Todd. I thought I'd fixed that... Doh!
See, this is why I post....


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## CliffyJ (Apr 29, 2009)

Here's the "platform" with non-shorting contacts (thanks Todd), a 3/32" rod throwbar, and saddle-type clamp for the rod. 




























The platform is 2"x2"x.5" at the moment. Kinda big, I know... 

===>Cliffy


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## CliffyJ (Apr 29, 2009)

Been tweaking things more, and resurrecting the stands and targets after all the surgery. Main efforts were centering the stand over the platform, and using 3/32 tube for the targets (after handling some real 1/16" tube, and comparing the SVRR stand). 




























The nagging thing I have at the back of my head now is, why not try to make a ground throw out of this? Instead of making it an indicator-only, why not try to make it an operator, as an option? Or both? But then, I try to remember the issues with that, such as:


A ground-throw operator needs some sort of holding means, like an over-center spring or a detent or something, to keep the point rails secure to one side or the other. 

It also should use a spring somewhere in the throwbar linkage.

The indicator stand doesn't need either of these, because it's just following the switch drive & point rails. But ideally, the platform would be usable as either an indicator or and operator, "slave" or "master," depending on whether there's a switch drive present or not. 

Thoughts? Opinions? 

===>Cliffy


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## CliffyJ (Apr 29, 2009)

For connecting a ground throw or switch drive to a turnout's throw bar, with a kink in it to give it a little springiness, what size of spring (or music or piano) wire should be used? I'm about to order some, but due to shipping costs and all, I'd like to get it reasonably right. McMaster has all kinds of sizes, but not in cheap little assortments to experiment with... 

Ideas?

[edit]

Just saw these assortments, not cheap but really covers the range,
http://www.brownells.com/gunsmith-t...-150-spring-asst--sku025150000-26217-476.aspx
similar,
http://www.brownells.com/gunsmith-t...ts/wolff-kit-15-sku969101500-26220-37165.aspx

[nuther edit]
Another assortment, in SS:
http://instrumentclinicusa.com/index.php?main_page=product_info&products_id=2271

I'd rather not blow the dough, if I knew approximately what size to get. On the other hand, a nice assortment is almost like a tool, for ongoing gauging of these sorts of things...


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## Homo Habilis (Jul 29, 2011)

Have you checked your local Ace Hardware? At least the two that I frequent have a small selection of music/piano wire and K&S metal shapes, tubing and sheet metal. Maybe one near you has them so you could choose a few different diameters.


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## CliffyJ (Apr 29, 2009)

That's a great idea, I'll check it out. Thanks HH!

[edit] Well, none really near, but our local "DoItBest" hardware store has a K&S display, maybe they have spring wire too, I'll check.


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## Naptowneng (Jun 14, 2010)

Cliff- The K&B True Value has a K&S display that I frequent. Come on down to O'Brien for a green beer...

Jerry


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## wigginsn (Jan 9, 2008)

Hi Cliff,

I used 1/16" K & S piano wire for these bolt barrel ground throws - you can just make out the bend in the closer one. Worked well.










Cheers
Neil


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## CliffyJ (Apr 29, 2009)

That's a great data point [edit] Neil [not Chris], thanks! Was that you who came up with that bolt/latch idea? I recently saw it in a GR issue flip-thru. Seems really straightforward and effective. 

Jerry, thanks for that. The green beer sounds good. Can't get there soon, but I'm almost tempted to ask you to please pick some up before ECLST, and just add it to my bill, haha!


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## wigginsn (Jan 9, 2008)

I 'borrowed' the bolt idea from OVGRS back in 2010, original web page here: 

http://ovgrs.org/track/switch-throws/

Cheers
Neil (Chris??)


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## CliffyJ (Apr 29, 2009)

Thanks for that link Neil (sorry for calling you Chris! Where did I get that? Alzheimer's kicking in I suppose...) It was great to see what they did with the cranks & choke cables. I was thinking about a right-angle adapter, using a crank, for the switch drive, and so it's neat to see it's been done.


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## CliffyJ (Apr 29, 2009)

About that rotary switch stand. I'll come clean, and admit I messed up: the legs are turned the wrong way. I'm sure some of you caught that. I did find a very few examples of legs oriented the way I have them, but by far, most have the legs spanning the space between the ties. Which totally makes sense. 

Here's an example of one going "my way," basically a thin frame that mounts on only one tie:
http://www.rmweb.co.uk/community/uploads/monthly_06_2011/post-8839-0-65714700-1306937177_thumb.jpg

Another, for a low stand, that was planted on a steel plate to make it work:
http://www.johnnyspages.com/mt_gambier_2003_files/15_small_switch_stand.jpg

But, those are exceptions. So I was going to remodel the rotary stand, to fix this oversight. Unfortunately, to keep the electrical bits underneath the same as the harp, I'm not finding a clear design path for that, because of the off-center rotary motion of the pin that moves the connecting bar.

So for now, I'm going to keep heading the way I was. But at some point, I think a proper rotary, with the off-center connecting bar linkage, will need its own special platform design (vs. the harp, which is centered and symmetric throughout). 

Oh well. The bright side is, ECLSTS next week!
===>Cliffy


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## CliffyJ (Apr 29, 2009)

The bad news was that though the Shapeways parts came in Friday, 2 parts were missing. So the switch drive project is on hold for 2 more weeks. 

The good news is that my local ("DoitBest" type) hardware store had the spring wire assortment within their K&S display (thanks Habilus), so I was able to get a nice selection. Off to find a "swing keeper," thanks to John for that idea (but I might still need that coupler-thingy to release the hook and get the cable out, we'll see).


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## CliffyJ (Apr 29, 2009)

I received the missing parts a couple days ago, and was able to spend most of the day building and testing and commenting on this prototype.

A ways to go still, but here's the state of things at this point.






Thanks for watching,
===>Cliffy


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## tmejia (Jan 2, 2008)

Great explanation video Cliffy. I like the push button feature.

Tommy
Rio Gracie


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## CliffyJ (Apr 29, 2009)

Thanks Tommy


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## toddalin (Jan 4, 2008)

Looks good.

My real negative is that it looks too be too big. Could it even be mounted right next to the rail at ground level without some undercarrage rubbing on it? I have stuff that will rub the old style LGB motors and they sit at rail height or below.


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## CliffyJ (Apr 29, 2009)

Thanks Todd. 
Correct, this cannot be mounted right next to the track. Making that connection, with the box mounted somewhat remotely, is my next challenge.


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## CliffyJ (Apr 29, 2009)

In making the turnout connection, I had a number of minor setbacks, the main one being the fit of the cable within the tube. Early on this thread, Riderdan brought up the issue of play, and, sure enough, today I've seen how big an issue it can be. All of the servo stroke can go into pushing the cable to one side if the tube's ID, or pulling it back against the other side (or a combination). 

The other main problem is that there is friction between the nylon tube and cable. I first tried 20' of it, and I couldn't quite push it through to the end. Serious bummer. 

So, I have some .073" ID / .125" OD tube on order (vs. the current .125 ID / .250 OD), which was the tightest affordable hard flexible plastic tube I could find. Hopefully it will take either cable or spring wire. 

Anyway, on a shorter cable length, the setup did well. Todd, the travel is currently 1/2", with some going into spring tension at either end, and some going into tube slop. This is after I let the board go through its auto-adjust routine, which seemed to take all that into account. The point rails are tight in either position.

Here it is, with the top of roadbed elevated to the same level as the top of the drive box.



















Thanks everyone for your suggestions, comments and viewing.

===>Cliffy


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## grsman (Apr 24, 2012)

*Pushrod*

CliffyJ
There are push rods in the model world that are tube inside a tube. They are very free moving with little friction. They use a short metal stub in each end for connection. The stubs are threaded and may be used for fine adjustment. There are also small Teflon tubes with a small cable inside for a push rod. There is practically no slop between the cable and tube. The fittings on the end of the cable are soldered on. One source is:
http://www.sullivanproducts.com
They have a lot of good stuff for connections and controls.
Tom


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## riderdan (Jan 2, 2014)

Cliff,

I'm curious as to how much difference you're seeing between a straight run and one where the control rod is curved. There's more friction in the curved application (your picture seems to show a somewhat greater than 90 degree bend)... is the servo still able to move the points easily with this bend? I don't suppose there's an easy way to measure the extra effort the servo has to put into overcoming the bent control rod.

I really like where you're going with this. I think that the ability to remotely mount the mechanical and electronic components will lead to a more prototypical look. One thing that's held me back from using automatic switches is how ugly those big black boxes are. Since my notional railroad is in the 20's, with hand-thrown switches, those switch machines kill it for me.

Please keep us updated.


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## Skeeterweazel (Feb 11, 2014)

Have you considered putting a spring on the points to pull them one way, then your servo could pull them the other way. If servo only pulling wire can be light. Just a thought. That's kinda how my air actuator works: spring in actuator pulls on points; when air applied it pushes.
Enjoying reading about your project.
Marty


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## CliffyJ (Apr 29, 2009)

Tom, that's a great resource, I'd not come across it. Of particular interest, which you probably saw, is their No. S522 .032 Push Cable & Golden Clevis, which includes 30' or cable, nylon sheathing and 8 couplings. Cable and couplings are brass plated for silver-soldering, so that's interesting. About a buck a foot. I'll have to look into these, particularly if my bulk cable/tube or wire/tube approaches don't pan out. Thanks!

Riderdan, I ordered an el cheapo digital fish scale the other day, which should come tomorrow. I'll be able to answer you better then. But the simple answer that when it's straight, there's less resistance; when curved, more. For example, when manually moving the points and then releasing, they snap back when the tube is straight; not so well when curved. But the servo still moves them ok. 

Yeah, I don't like the boxes either. I'm modeling ~1875-1900, and I'd rather have only harp stands exposed... 

BTW, the tube here is only 2 feet long. I was hoping to get it to 10ft or more. The reason is that one could house multiple units in a single enclosure and / or scale structure, adding a shared power feed at that point, and perhaps a multi-channel RC relay board. 

Hi Marty, if you're suggesting that a far-side spring would help keep the cable taught and therefore reduce binding, that makes sense. Not sure how that would affect the driver board's auto-calibration thing, but it's worth checking out, thanks for the thought. [edit: I don't see an easy way to get a spring in there, so I'll hold off and see how well the smaller tube does tomorrow].

Thanks very much guys!
Cliff


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## Beddhist (Dec 17, 2013)

Cliff,

You are probably aware that many tractors, ride-on mowers and other such machinery use solid cables for throttle and choke. They have to work in very dirty environments, so they may do the trick for you. There is quite a bit of friction to overcome, though. Have you spoken to anybody in a lawn mower shop or an agricultural servicing place?

The method to pull against springs is used on my Walker mower's park brake, while throttle and choke use the solid push/pull cables.

Cheers,
Peter.


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## CliffyJ (Apr 29, 2009)

Hi Peter, yes I have, and yes they're very effective. But I'm trying to go with products that are cheap, and that can be bought in a coil (vs. a set length of, say, 3' or 4'). 

Earlier on, Neil posted a link to a great article on using proper choke cables: 
http://ovgrs.org/track/switch-throws/

Cheers back at you,
Cliff


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## Beddhist (Dec 17, 2013)

These kinds of cable used to be sold in bulk to the shops. I don't know whether that is still the case.


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## CliffyJ (Apr 29, 2009)

I'm sure you're right Peter, and I'll keep my eyes peeled. Please let me know if you run across it.
Thanks,
Cliff


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## lotsasteam (Jan 3, 2008)

another idea!


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## CliffyJ (Apr 29, 2009)

Now that's practical, funny and fascinating, all at the same time. Thanks Lotsa!


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## CliffyJ (Apr 29, 2009)

I received the smaller sheathing tube, and cut a 10' length of that and the 1/16" SS cable. Too much resistance still. 4 or 5 ft would work, but I really would like to get that friction down as far as possible.

So, as some prognosticated, I'll get a coil of spring wire, and mess with that next. Actually 3 coils, in different sizes for comparison. McMaster has it in SS for a great price, but as always, the bummer is the shipping charge. 

If that doesn't get me a decent 10 feet of actuation, I'll either try the kit offered by Sullivan, or call it a day and determine whatever max length seems workable.


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## CliffyJ (Apr 29, 2009)

A little update.

Last weekend I compared the cable to spring wire (.031, .041, .051 dia's, with and without spray teflon lube), run thru a 1/8" od x .073" id nylon tube. The .041 spring wire worked best, but was still too sticky for the switch machine to happily deal with. Still, that's what I used for subsequent testing.

By "happily," here's what I mean. The controller board has an auto-adjust routine that, when it senses the servo having too much resistance, calls that the end of travel. Then it goes the other direction, and does the same. If there is too much resistance in the cable, the board will think that's the end of travel, and the points won't be thrown all the way.

I tried 8', 6', 4', 2' and 0' cable lengths, with straight, and (as possible) 180-degree, 360-degree, and reversing 180-degree paths, using a digital scale to read the peak force needed to throw the turnout. The more extreme the cable path, the more resistance, and force required, as you'd expect. 

The threshold resistance for the board (Tam Valley Depot "Singlet II") is about 1/2 pound. The lengthier / more extreme cable paths required more force than that, so the board didn't auto-calibrate for those. 

So, I ordered 2 sample push-pull cables from RC product manufacturers, to see how the pro's do it. Today I compared everything, as follows (dimensions are approximate).

1. Sullivan cable: .032 SS plated cable (7x1x.014) in nylon tube (.070 od x .040 id)
2. Dubro cable: .06 nom steel cable (7x7x.006) in nylon (?) tube (.125 od x .095 id)
3. Spring wire: .041 SS spring wire in nylon tube (.125 od x .073 id)
3. McMaster cable: .06 nom SS cable (7x1x.020) in nylon tube (.125 od x .073 id)

Here's the setup, using 4' runs, no turnout attached, 










Average push/pull forces were:
1: .10 lbs
2: .14 lbs
3: .41 lbs
4: .32 lbs

Long story short, #1 was too flexy; #3 & 4 (the ones I'd messed with last weekend) were too sticky. #2 seemed the best, but the tube is unmarked, so I don't know where to get it in bulk. So I tried the Dubro cable and my prior tube, and it worked as well.

Here's a brief vid of it working.






I learned several things through this, which I'll type up a bit later.

Thanks for viewing,

Cliff


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## riderdan (Jan 2, 2014)

Appreciate the update Cliffy. I'm following this closely, since as I mentioned, the sight of electric switch machines isn't my favorite. I think that remote mounting in a straight line would almost always work on my little layout, since I have relatively few switches an they're all within "reach" of a logical building location. So the ability of the system to work around 180 degree turns isn't an issue (for me)...

Anyway, be sure and share your conclusions. And thanks for doing all the thinking, testing, and sharing.


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## wigginsn (Jan 9, 2008)

Nice work Cliff.

When I used the choke cable mentioned a ways above, the force needed reduced drastically (by feel) once the cable was buried in crusher dust and the sheath could not move at all. Also the movement was very positive as there was zero flex in the sheath.

Might not be practical for above ground installs but I'd be keen to see if the measured throw force drops if you bury the cables under 4" of wet rock dust.

Yeah, yeah - more work.. 

Cheers
Neil


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## CliffyJ (Apr 29, 2009)

Thanks for the encouraging words, guys! 

Riderdan, I agree; if I use these, the cable will most likely run straight (-ish) to a convenient operating location. But, I don't know what obstacles I'll run into, so... 

Neil, that's a great point. I stapled the tubes down, but not firmly (didn't want to depress them). So yes, they flexed. I'll see if there's a way to more firmly hold it in place, and check it out.

Thanks again guys,
Cliff


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## CliffyJ (Apr 29, 2009)

I learned a few things last weekend and yesterday, starting with raw output force of different drives. 
By "servo drive," I mean the thing I've been messing with.

Piko (similar to LGB, but I don't have an LGB): 0.22 lbs causes spring to flip; motor put out 0.40 lbs
Aristocraft: 0.20 lbs 
Train-Li: 1.02
Servo drive (resistance when auto-endpoint-setting kicks in): .43 lbs (@ crank radius of .47")
Servo drive (stall force): 4.80 lbs (@ crank radius of .47")

This heavy-duty servo puts out a lot of force, more than the other components (e.g., the servo mount) would want to see. 

The automatic calibration of the board, however, was causing me problems. I set up several wire & tube configurations last week, and all but the most simple had more mechanical resistance WHILE THROWING than the board's resistance threshold. So, while going through the calibration routine, the controller would see this resistance, and assume an endpoint was reached.

This is exacerbated with increased complexity of the cable path. I found that additional length and curvature, especially reversing curves, really drove cable resistance up. At ten feet, with reversing 3-bend, the wire-in-tube simply locked up, and spray teflon lube didn't help. 

Additionally (and this is a little hard to describe), a small resistance at the throwbar (say, sticky points) caused a sort of traffic jam back along the cable path, as the cable went from one tube wall to the other. 

Point being, there are a number of variables in the tube / cable, so simpler the better. 

Having said all that, I received some good news this morning from Duncan McCree, designer of the controller board. Here's the jist of the Q&A:

CJ: Can I manually set the ends of travel beyond what the automatic method thinks they should be? The unaided auto method feels the resistance in the tube, and stops too soon. But if I help the servo with my finger, the positions end up ok, and the servo still stops properly. 

DM: Yes this is a perfectly good way to set the end points - wait until the servo arm gets where you want and then push back to get it to accept that position.

CJ: Even if the servo does stop where I want it, does the above sound damaging in some way?

DM: No it won’t cause any harm.

CJ: Is there a way to increase the auto resistance amount?

DM: Every time it runs it ups the resistance level a bit - so if it stops too soon try it a again.

CJ: I'd like to try manual setting with the pushbuttons, but I couldn't work out the instructions. Line 1 of your chart says: "Hold Button | LED1 flashing | Set the endpoint for Button 1." Which button? Do I force the servo into position before this, or after, or ? 

DM: You hold down one of the buttons until the LEDs flash. Then you use the 2 buttons to move the servo arm to the correct position. You don’t move the arm before you start.​
There are a number of additional things to resolve in this project, like final mount design & final cable / wire selection & attachment method. I'm coming back to the idea that track-side spring is needed. 

Thanks for viewing!
Cliff


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## Greg Elmassian (Jan 3, 2008)

I thought CV50 allows you to set the force during calibration?

The manual operation is a bit tricky, you have to watch what mode you are in with the lights and it's easy to go one step ahead of where you want to be.

Greg


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## CliffyJ (Apr 29, 2009)

Right you are Greg, via DCC I was able to up the auto-adjust current (CV50) to 40 (vs. the default of 24), which seemed to work well. Thanks for that tip / reminder! 

I did the auto-adjust a number of times today, and sometimes the servo kept buzzing, as you've mentioned elsewhere. Usually, it shut off after about 5 or 10 seconds. But when it didn't, I'm assuming that the adjustment needs to be backed off. And per Duncan's instructions, I was able to tweak that manually (via buttons).

Main thing, the auto-adjust process works far better now (with the increased current threshold). This was with a tightly convoluted 4' cable.

Though I'm using DCC, I'm interested in maintaining flexibility for other folks. So, since "you can program all functions with the buttons," I've asked DM how to do that for CV50 (adj current), CV35 (speed) and CV37 (direction). 

BTW, one little thing that helped was putting tag lines on the jumpers. This is nylon button thread, melted at the ends and crazy-glued at the knot. Fluorescent orange or red would probably be better, if it were dropped while programming _in situ_. Anyway, it saves having to use needle-nose pliers. Sorry for the suckie pic, but you get the idea. 










Cliff


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## CliffyJ (Apr 29, 2009)

I did some some final testing this morning, and have come to my personal opinions on best push-pull cable products to use on this project, going forward. This is after working with 3 kinds of spring wire, 5 kinds of cable, and 6 kinds of nylon tube.










My criteria began with corrosion resistance, availability, the ability to easily cut it to length, cost, and a minimum length of around 4 feet. These final selections are based on smoothness of operation and flexibility. The bronze and ss cables worked equally well, except that one can solder the bronze (should that become important). The bronze cable is slightly more flexible. 

Here's the clickable links,
http://www.mcmaster.com/#8908t32/=wwm6pq 
http://www.mcmaster.com/#3462t53/=wwm6gi 
http://www.mcmaster.com/#9685t1/=wwm7ly 

Thanks for viewing,
Cliff


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## fyrekop (Sep 20, 2011)

Cliffy: It looks great and Now that you've done all the hard work ....... 
Cost per unit including Train-Li DCC switch machines.
WAG (wild a.. guess) for a site with 16 turnouts including those so cool 
control panels you made. (Looking at LARGE spare change jar)
Alan W.
PS: Standard Aristocraft manual throws not working well around fine dust and rocks in Southeast AZ.


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## Greg Elmassian (Jan 3, 2008)

I think that my pneumatic system is probably much greater in cost after this amount of work.


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## CliffyJ (Apr 29, 2009)

Hi Greg, did you mean lesser in cost? 

Hey Alan, thanks for the vote of confidence. The raw costs are hovering around $70, per unit (vs. ~$45 for the Train Li). I'm still slowly working on the design, especially re. the throwbar connection and spring approach there. 

As for the control boxes, I'm glad you liked them. All in, I blew about $400 (for 3 panels + the receiver box). The big drivers were the laser-cut back panels, rc relays, and boxes. If you're serious about going in that direction, I'd be glad to send you spreadsheet / parts list.

CJ


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## riderdan (Jan 2, 2014)

Cliffy,

Thought I'd post this here, as you were talking about remote mounting switch machine mechanisms.

Here's my test version:



















Here it is in operation:






I think your method of flexible tube is a lot more versatile than my straight brass tube, but since I can easily find places within a foot of the switch for the remote servo part to be mounted, this works fine for me. This is really rough, as I was just trying to figure out if it will work... but it's a Tam Valley servo singlet and the push-button controller running the servo.

Later today (or tomorrow) I will mount a harp switch stand on the opposite side to give a visual cue as to which way the switch is thrown.


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## Greg Elmassian (Jan 3, 2008)

yeah, lesser ha ha... no more Scotch...


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## riderdan (Jan 2, 2014)

With the harp stand...













The reason the harp (and points) "jump" in the first half of the video. is that the servo is loosely coupled to the throw arm, which allows the spring in the switch to close that last little bit of travel of the points. I need to adjust the servo so that it's equalized, as it currently isn't.


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## CliffyJ (Apr 29, 2009)

Nice job with the harp stand Dan, that's just what I'm ultimately interested in. And I'm glad you're delving into the diy servo control. Those TV singlets are pretty awesome, right?


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## riderdan (Jan 2, 2014)

CliffyJ said:


> Nice job with the harp stand Dan, that's just what I'm ultimately interested in. And I'm glad you're delving into the diy servo control. Those TV singlets are pretty awesome, right?


Thanks Cliffy. 

Yes, the singlets are a really neat piece of kit. I fiddled around with building my own controllers using a 555 timer IC, but ultimately decided that since I need ten or twelve of them, the price was easily worth it. Plus I think the Tam Valley units are a good deal smaller than I could make a roll-your-own PCB.

I have some Azatrax pulsed IR train detectors that I'm going to use to run a set of crossing gates near my town. I've already modified one to run off a servo--at some point I'll start a thread about that. I'll just hook the detectors to the singlets and *poof* I'll have working gates that stay closed until the last car goes by.

My only concern is how everything will stand up outside. I found some good info on waterproofing hobby servos (intended for people building RC submarines) that I tried to follow. I guess we'll see once they've been out for a year or so. At $6 a pop, it wouldn't be a big deal to replace the servos. I potted the PCBs in silicone, so they should be OK.

Anyway, glad you liked the harp stand. I have a couple switches that are too far from the "edges" of my layout to easily see which way they're thrown, and I think the big "flag" on the harp will make it so I can tell from most anywhere which way a set of points is thrown.


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## CliffyJ (Apr 29, 2009)

I see, you're placing the servos without a box. I was wondering about that. I'd be interested in understanding that sort of waterproofing. 

I could picture a sort of bellows, like a rubber bag that enveloped the entire servo and arm, clamping the body to an external mount, and penetrating the rubber for just the wires and the throw-bar connection. But I have no idea how you're approaching it.

Feel free though to continue on this thread, or start your own. I'm sure it will be interesting either way. Best luck!


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## riderdan (Jan 2, 2014)

CliffyJ said:


> I see, you're placing the servos without a box. I was wondering about that. I'd be interested in understanding that sort of waterproofing.


I've seen several ways suggested to waterproof them--not all of which seemed very sensible to me  The site I found most informative was societyofrobots... there's a whole section there on waterproofing ideas.



CliffyJ said:


> I could picture a sort of bellows, like a rubber bag that enveloped the entire servo and arm, clamping the body to an external mount, and penetrating the rubber for just the wires and the throw-bar connection. But I have no idea how you're approaching it.


It's funny you mentioned this, since one of the common (but silly-sounding) suggestions was to put the servo in a balloon!

Actually, I will probably do my best to seal the servos up with silicone, much like potting a PCB. I'll open them up and silicone the circuit boards first, then close them and do the outside. If the case is covered in silicone, including where the wires go in, only the hole for the post that the horn mounts on needs work. I'm going to try some silicone o-rings to seal that up. Filling them with mineral oil sounds too complicated for me, and I've had poor success with CA as a waterproofing agent.

The controller PCBs will be encased in some sort of enclosure. I've thought about little plastic food containers that seal--siliconing up holes where wires protrude and then adding desiccant packs to help keep moisture from attacking the electronics. I'm still thinking all this through.

I'll keep you posted on how it all works out.


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## fyrekop (Sep 20, 2011)

When in the Marines and worried about water getting into rifle and pistol barrels we didn't have access to balloons. However Trojan made several items that worked quite well.


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## Dan Pierce (Jan 2, 2008)

WOW, waterproof and lubricated also!!


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## fyrekop (Sep 20, 2011)

And they didn't block the barrel if the weapon needed to be fired suddenly.


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## riderdan (Jan 2, 2014)

I thought I'd stick this on the end of Cliffy's thread, rather than starting a new one.

I've got my first servo-controlled switch on the layout. I'm using a Tam Valley servo singlet, which gets both power and DCC signal from the track. The amperage draw is nominal when the decoder is just listening, and since at most I would ever move two of these simultaneously I think it's ok. My layout is rather on the small side--small enough that I don't expect to ever run more than two locomotives at a time.

Here are some pix




This is a section that hasn't been leveled or ballasted yet, but you get the idea. The brown plastic box contains the singlet and servo. The brass tube holds the box a fixed distance from the switch and provides some stiffening for the brass rod that moves the switch points.

Once this section is ballasted, I expect the ballast to cover most of the brass tube. The brass "clip" that holds the tube to the ties will weather (or be painted, I haven't decided yet) to a deep brown that I expect to blend in to the background or to be covered with ballast, since the top is within 1/16" of the top of the ties. So the only visible indication will be the small (3x2x2) box nestled under the tree.

The harp stand on the right will also look better once the ballast hides the fact that the brass stip is holding it up 

The servo and singlet were waterproofed with proven methods from the RC world. I disassemble the servo and greased the servo shaft with marine grease. Then I reassembled it and dipped it in plastidip. This should waterproof the servo quite thoroughly--I've seen servos done in this manner operating under water. The singlet was also coated with a generous coat of plastidip before installation in the housing.

The housing is built from laser-cut styrene and is sealed top and bottom. There are very small vent openings just below the "roof" that should allow any water that gets in to evaporate. Since I leave the track power on most all the time, I expect the warmth of the circuitry to assist with the process of evaporation and to help prevent condensation. 

The four brown "blobs" on the closer end are the singlet "fascia" controller's two lights, push-button switch, and mounting screw. There are holes through the side for these that were sealed on the inside with silicone. The button allows for manual operation of the switch points without resorting to a throttle.

By the way, if you're interested in animation, I'd highly recommend looking in to the servo singlets. They're not very expensive (for what they do) and can be thrown from a throttle or manually from the "fascia" controller, or triggered by an electronic input. It's a really neat piece of kit. I'm thinking I will use these for crossing gates and some other animation I want to get to eventually 

Overall, I'm pleased with how this has turned out. I was hoping to have electronically controlled switches (certainly in the less-accessible ares of my layout) but without the unsightly track-side plastic boxes that LGB, Piko, or TrainLi use. This method allows me to have the appearance that the switches are controlled by the harp stands, even while they are throwable from the throttle. And the very visible harps provide an easy to see indication of how the points are aligned. Sort of the best of both worlds. In addition, getting the power and signal from the track at the point where the mechanism is eliminates the need for any additional wiring.

As a last note, I've set up a RaspberryPi with JMRI connected to my NCE PowerPro command station. This means that the layout--both trains an switches--is controllable from any web browser. This afternoon I added a webcam to the Pi so I theoretically could start a train running in the morning and watch and control it from my basement office during the workday. Not that I'd ever do that, of course


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## CliffyJ (Apr 29, 2009)

riderdan said:


> Overall, I'm pleased with how this has turned out. I was hoping to have electronically controlled switches (certainly in the less-accessible ares of my layout) but without the unsightly track-side plastic boxes that LGB, Piko, or TrainLi use. This method allows me to have the appearance that the switches are controlled by the harp stands, even while they are throwable from the throttle. And the very visible harps provide an easy to see indication of how the points are aligned. Sort of the best of both worlds. In addition, getting the power and signal from the track at the point where the mechanism is eliminates the need for any additional wiring.


That's wonderful work RD. You're accomplishing what I hoped for (but haven't yet achieved), the harp stand as the signal, with the remote (non-trackside) DCC throw. Great job!!

I agree, those singlet kits are an excellent value with lots of application.

When I get back to this project, I'll have to ask you for some specific info / vid's on the waterproofing of servos and boards. Or, please feel free to post it here & sooner.

Also, I didn't quite understand how you were securing your servo assembly, relative to the turnout. Is there a solid brass rod moving inside an outer brass tube? Also, is that a machined brass interface at the ties? Maybe with the outer tube soldered on?

===>Cliffy


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## Totalwrecker (Feb 26, 2009)

Click on the pic Ciffy.
I think I see the small rod that actuates the harp also coming out of the tube going into the switch.
Dan, I like your over lapped compressed wye. 
John


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## riderdan (Jan 2, 2014)

Totalwrecker said:


> Click on the pic Ciffy.
> I think I see the small rod that actuates the harp also coming out of the tube going into the switch.
> Dan, I like your over lapped compressed wye.
> John


Thanks John. I wanted a "real" wye but the only way it would have fit was as an R1 which I wasn't pleased with. The overlap allowed this R5 wye to just squeeze in.

Cliffy, John is right--there's a brass rod inside the tube. The piece trackside is a flat sheet soldered to the tube. The sheet has two "pins" that fit in the screw holes in the tops of the ties. Then a u-shaped clip holds the sheet down onto the ties so the pins don't work free. On the servo side I bent a brass sheet into a servo mount and soldered it on that end of the tube. So the tube is what keeps the fixed distance between the servo and switch.


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## fyrekop (Sep 20, 2011)

RD, 
Are you using the Tam Valley Micro singlet? And can the tube to be adjusted for distance from track? Several of my turnouts are located close to concrete walls so not as much space as you have. Love the idea of no wires.
Alan


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## CliffyJ (Apr 29, 2009)

Seems like I missed your 11-10-15 posts Dan, looking really fine. 

Alan, not sure which one Dan's using, but I used the Singlet II, with a heavier-duty servo. Lots of functionality to this unit. The auto-align routine is neat, it automatically figures out how far to throw the points. 

I was using the cable in a flexible tube, at around 5'. But I like the brass tube approach, because you can solder directly to sheet like Dan did.


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## riderdan (Jan 2, 2014)

fyrekop said:


> RD,
> Are you using the Tam Valley Micro singlet? And can the tube to be adjusted for distance from track? Several of my turnouts are located close to concrete walls so not as much space as you have. Love the idea of no wires.
> Alan


Alan--these are the Tam Valley micro singlets. I had hoped that between the micro servo and flexibility in the brass actuator rod that it might be possible they would allow you to cut the switch from the back end when it wasn't aligned for that route. But unless the locomotive was really heavy this won't work. At least, my LGB 0-6-6-0 Mallet, which seems like a monster to me, won't push the points aside. Bummer.

It would be really simple to make the brass tube whatever length you wanted. This particular one is "full length" for the pieces I bought from Hobby Lobby, but it could be as short or as long as you wanted. In Cliffy's experiments (where friction was an issue) the nylon tube and actuator weren't running in a straight line--I don't think that's at all an issue for a setup like this where the brass rod and tube are perfectly straight. So however long a brass tube you could find would be the upper limit. The lower limit would be how close the mechanism can be to the switch and still look better than "normal" G-scale switch machines.


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