# CROSSOVER & SWITCH DEAD SPOTS?



## PSLIMO (Jan 4, 2011)

Hi,

I'm new to large scale and have a question. From a quick search of this huge forum this seems like the place to ask. My question:

Running small Eggliners and Lil' Critters across crossovers and switches I'm experiencing dead spot's at slower realistic speeds if not a total stall at the plastic insulator's on the PIKO track I'm using.

Is there a simple capacitor fix to carry current past these dead spots? Is there a simple way to have both sets of wheels used as electrical pickups?

Thanks in advance,

Phil


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## Axel Tillmann (Jan 10, 2008)

Phil:

Yes there is, but it is a little bit thorugh the back door: Using a DCC decoder or a DCC decoder with sound. We have sucessfully experimented with ZIMO decoders putting capacity on the +/- decoder outputs which feeds the logic that continues to control the power to the motor. The reason why you can't use a capacitor directly is the change of polarity on the track. Capacitors with the right storage capacity are polarized, so when you either put the loco incorrectly on the track (assuming you only run one way) or switch the power supply to reverse the capcitor blows. But with the decoder in place you do not have to worry.

As far as using both axles for power pickup, that would only work if you have a second motor block and take its axle. Alternatively you can try to buy a set of LGB pickup shoes and construct an LGB like "off center" mounting and then run the wires into the engine.


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## toddalin (Jan 4, 2008)

Posted By Axel Tillmann on 04 Jan 2011 05:58 AM 
Phil:

The reason why you can't use a capacitor directly is the change of polarity on the track. Capacitors with the right storage capacity are polarized, so when you either put the loco incorrectly on the track (assuming you only run one way) or switch the power supply to reverse the capcitor blows. 


Sure it can be done using a couple capacitors and diodes. However, the capacitors are large and fitting two into a critter or eggliner would be no easy task. If you want more axles to pickup power, you can add a trailing car with "live axles" and a jumper wire to the engine.


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## PSLIMO (Jan 4, 2011)

So, all layouts with these smaller engines have the same problem? This wouldn't make the Critter a very realistic switcher IMO...

That said, which would be the method most often used to deal with this problem. A second car that has pickups already for maybe lighting cabled to the engine. Or, is a second set of pickups on the engine a simpler way. Does Aristo Craft have these type of add on kits or solutions for their trains? I haven't been able to locate any after market solutions either.

I also was searching for some aftermarket way to keep the lights at a constant brightness without much luck. 

Phil


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## PSLIMO (Jan 4, 2011)

This is the small layout I have around our Christmas Tree. The engines at a slow crawl has such a better look. I have a feeling that this layout will continue to grow each year as I'm enjoying the hobby. 



http://www.mylargescale.com/Portals/0/activesocial/profiles/9363/gallery/82/lg/4.png


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## Axel Tillmann (Jan 10, 2008)

We cary the 2 pin plugs as well as the Banana plugs used in LGB setups. Those you can use to crete such a solution. Not elegant however, but workable.


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## aceinspp (Jan 2, 2008)

I would tend to think that the Aristo Egg liners and the Critter would have all four wheels as pick ups. Later RJD


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## PSLIMO (Jan 4, 2011)

Unfortunately they don't and that's the problem. The Eggliners look like it would be easy to add pick up shoes between the wheels like the ones Piko Loco's have. However, I'm new at this and hope to draw from the experience of this board for proven methods.

Phil


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## Torby (Jan 2, 2008)

Of course egg liners have pickups on all 4 wheels. I see it all the time when cleaning the wheels at the Botanic.


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## Dave Meashey (Jan 2, 2008)

Just put my Eggliner on my lap and checked all four wheels with an old HO power pack. All four wheels do pick up power. These units do have a relativaly short wheelbase. The same power unit is used in the trucks of the RS3 diesel locomotive, BUT that locomotive has two trucks to help span the dead spots in switch frogs and crossing frogs. The small units, like the Eggliner and the Lil Critter, are prone to stalling over frogs at lower speeds, especially if one or more wheels does not have optimal pickup. The newer units have the Aristo "MU" cables. Connecting two or more of these small units with the Aristo jumper cables can help spread the power through such dead zones as frogs. 

I'm afriad that I'm not too clever with the electronic devices that were mentioned above. My unit predates the MU cables, but I tend to run it faster, so I have fewer problems at frogs. I do see the lights blink as it traverses a frog, but it's on its way again before it stops dead. 

David Meashey


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## PSLIMO (Jan 4, 2011)

Once again, I'm glad I found this forum.

After some more trial and error after reading the last post. It's not that both sets of wheels don't conduct from the track. It's that the span of the frogs on the crossover are the exact wheelbase of the Eggliner! Very frustrating and I'm back to square one...

Phil


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## Totalwrecker (Feb 26, 2009)

There was an article in Garden Railways mag a couple of issues ago where a gent added thin strips of brass across the plastic rail of a crossover. He wired them and solved your problem. 
Sorry I don't remember the issue. 
John


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## Totalwrecker (Feb 26, 2009)

Posted By Totalwrecker on 05 Jan 2011 01:05 AM 
There was an article in Garden Railways mag a couple of issues ago where a gent added thin strips of brass across the plastic rail of a crossover. He wired them and solved your problem. 
Sorry I don't remember the issue. 
John A couple of corrections;
1 The issue was Oct '09... a bit more than a couple....
2 He used brass channel to make the plastic rails 'live'

Looks easy enough to do.

John


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## PSLIMO (Jan 4, 2011)

I received responses from both Piko and Aristo Craft today on this problem. Piko emailed this response:

_*"Dear Mr.Phil,*_

*Thank you for your request. Since the frogs are made of the point of plastic, it can be when driving slowly come to a halt. This is by design and in switches of other manufacturers*


_*Best Regards*_



_*Hans-Josef Börgers*_
_*Produktmanagement"*_

Aristo Craft responded by phone that the only way to prevent the stalling if I choose to use switches and crossovers with Lil Critters or Eggliners is to wire an additional powered car to it and offer no wiring kits for this purpose.

Both local hobby stores suggested using aluminum tape or adhesive flat copper wire to fill in most of the plastic gap being careful no to short anything.

I guess it's time to purchase a larger loco if I want slower more realistic speeds...

Phil


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## PSLIMO (Jan 4, 2011)

Hey Guy's

This is driving me crazy!

I've decided that the outer rails have the same polarity on the 30 degree crossover. Those are the easiest to bridge. If I remove the 5 1/2" sections of the four outside rails. Dremel out the plastic part of the frog that completes that part of the 30 degree crossover and replace them with new 6 1/4" 30 degree angled rails butting together. The wheels will close the remaining tiny gap if any and the problem is solved!

Although this might give Piko something to think about, it might not be a good idea from a cost effective manufacturing point of view and the limited amount of loco's it effects.

However, it would be if they had to explain to their 6 year old daughter why the train always stalls!

I'll let you guy's know if it works as planned.

Phil


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## Torby (Jan 2, 2008)

Such is the case with short wheelbase 4 wheel locos. If they get both wheels on one side on an insulated spot, they stop. Often they have enough momentum to reach the other side.

It's just the nature of the beast.


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## Chata86 (Dec 5, 2010)

Woha. I've never thought about exploding electrolytic capacitors on the trains before. I suppose fast reversing could easily have damaged the old analog sound system in my 2080S.

Also... I wonder if those super capacitor kits aren't that great of an idea for non DCC trains?


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## sandbarn (Feb 13, 2010)

First, I don't use track power. But I was thinking you might try looking at different brands of switches, such as Llagas, Sunset Valley, SwitchCrafters. These don't have insulated frogs but use a micro switch at the throw to direct power. Others here can correct me if I'm wrong. Good luck.


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## Dan Pierce (Jan 2, 2008)

I have added super caps to my sound modules with great success. You must have a current limiting restistor for charging, and a diode for the discharge path. 

LGB has been doing this for many years, all F7B units have super caps on the sound units. 

For track power, I find it easier to just add power pickups to the tenders or 1st car behind the engine for better lighting and motor power.


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## Dave Meashey (Jan 2, 2008)

You know, this could be a business opportunity for one of the small manufacturers of after market accessories and details. If somebody could create either a flywheel kit or an "electronic flywheel" kit that would allow these critters to coast through the dead spots at lower speeds, there could be a good market for that product. 

Also, G-Scale Graphics' Critter Control is another viable solution to the problem, and at a very reasonable price. 

Just raising this up the flagpole to see whether anybody salutes, 
David Meashey 

P.S. This thing simply coasts on its ball bearing wheels, so it doesn't have time to stall before it's over the dead spots.


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## Axel Tillmann (Jan 10, 2008)

Posted By toddalin on 04 Jan 2011 11:17 AM 
Sure it can be done using a couple capacitors and diodes.
Tod I am interested to learn how you switch the polarity of the capcitors (that face the motor)







The problem is not the polarity change of the track power to the capacitor (a simple diode bridge fixes that







) but now we have the motor connected to the capacitor and we need it inverted and that automatically. Sure you can do it with a whole set of electronic - why not then put a motor controller in (i.e. DCC board) and you are done for the day.


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## Axel Tillmann (Jan 10, 2008)

Posted By PSLIMO on 05 Jan 2011 08:39 PM 
Hey Guy's

This is driving me crazy!

I've decided that the outer rails have the same polarity on the 30 degree crossover. Those are the easiest to bridge. If I remove the 5 1/2" sections of the four outside rails. Dremel out the plastic part of the frog that completes that part of the 30 degree crossover and replace them with new 6 1/4" 30 degree angled rails butting together. The wheels will close the remaining tiny gap if any and the problem is solved!

Although this might give Piko something to think about, it might not be a good idea from a cost effective manufacturing point of view and the limited amount of loco's it effects.

However, it would be if they had to explain to their 6 year old daughter why the train always stalls!

I'll let you guy's know if it works as planned.

Phil 
The two out rails have only the same polarity if this crossing is not part of a loop. So if you uyse this in a swtiching yard screnario, then you theory works. But manufacturers cannot offer this solution because they can't restrict the usage of the crossing to one application. The perfect way to make this an all metal solution is to insulate all 4 tracks from the outside and hook up in a clever way a polartiy changer (an easy task in DCC - more involved in analog).


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## Axel Tillmann (Jan 10, 2008)

Posted By Dave Meashey on 07 Jan 2011 06:26 AM 
You know, this could be a business opportunity for one of the small manufacturers of after market accessories and details. If somebody could create either a flywheel kit or an "electronic flywheel" kit 



Dave: 

In DCC the capcitor solution is also very often referred to as "electronic flywheel". So your wish has already come through for analog and DCC since the DCC boards are becoming now even more popular in analog. Why, because they provide even backemf and other functionality (including all the integrated sound capabilities) that customers want.

It is like the transition in the old day in the electric drill market. I remember my first Bosch drill and then 5-6 years later the first Bosch electronic drill - what a difference that was. Once you experience electronic motor control - you never go back


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## Dan Pierce (Jan 2, 2008)

One thing to note on 90 degree crossovers, LGB has metal powered rails in the middle of the crossover, Aristo has plastic rails, so you have approx. 3 inches of non metal to traverse and with a 2 axle engine, you can loose power pickup especially if the crossover is not level(engine is on 3 wheels, 2 on plastic rails and one that should be on metal is in the air!!!


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## toddalin (Jan 4, 2008)

Posted By Axel Tillmann on 07 Jan 2011 07:01 AM 
Posted By toddalin on 04 Jan 2011 11:17 AM 
Sure it can be done using a couple capacitors and diodes.
Tod I am interested to learn how you switch the polarity of the capcitors (that face the motor)







The problem is not the polarity change of the track power to the capacitor (a simple diode bridge fixes that







) but now we have the motor connected to the capacitor and we need it inverted and that automatically. Sure you can do it with a whole set of electronic - why not then put a motor controller in (i.e. DCC board) and you are done for the day.





Follow the link and learn a new trick.









Give your train the ability to ignore dirty track


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## PSLIMO (Jan 4, 2011)

Hey Guy's

Thanks for all the helpful insight to this problem. After reading the posts again I decided it might not be wise to attempt to modify the switches.

I ran across this company http://shourtline.swl4.com/ that makes solutions for all kinds of things. After talking to them directly, they said they could put a unit together that would work with the stock Eggliner.

Apparently, if you put 2 capacitors back to back they become bi-polar and the unit will work in both directions. They were going to experiment with different size capacitors to give me 2 wheel revolutions at 20 volts when the track power was lost so not to greatly effect the train while slowing down. At slower speeds the unit should provide more than enough to clear a 1" long frog. The nice thing is the unit would also cure the flickering lights issue.

I hoping to have something shipped to me next week.

Phil


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## toddalin (Jan 4, 2008)

Posted By PSLIMO on 07 Jan 2011 12:19 PM 
Hey Guy's

Thanks for all the helpful insight to this problem. After reading the posts again I decided it might not be wise to attempt to modify the switches.

I ran across this company http://shourtline.swl4.com/ that makes solutions for all kinds of things. After talking to them directly, they said they could put a unit together that would work with the stock Eggliner.

Apparently, if you put 2 capacitors back to back they become bi-polar and the unit will work in both directions. They were going to experiment with different size capacitors to give me 2 wheel revolutions at 20 volts when the track power was lost so not to greatly effect the train while slowing down. At slower speeds the unit should provide more than enough to clear a 1" long frog. The nice thing is the unit would also cure the flickering lights issue.

I hoping to have something shipped to me next week.

Phil
This methodology is what is in the link that I posted.


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## Axel Tillmann (Jan 10, 2008)

Posted By toddalin on 07 Jan 2011 12:00 PM 
Follow the link and learn a new trick.







Give your train the ability to ignore dirty track 
That is unfair







Two capacitors - and I am wrecking my brain how you do this with a couple of diodes and one capacitor









They should have called the headline Dirty Trick - not Dirty Track


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## toddalin (Jan 4, 2008)

Posted By Axel Tillmann on 07 Jan 2011 04:12 PM 
Posted By toddalin on 07 Jan 2011 12:00 PM 
Follow the link and learn a new trick.







Give your train the ability to ignore dirty track 
That is unfair







Two capacitors - and I am wrecking my brain how you do this with a couple of diodes and one capacitor









They should have called the headline Dirty Trick - not Dirty Track




Is fair. Go back and look at my post.









"Sure it can be done using a *couple* capacitors and diodes. However, the *capacitors* are large and fitting *two* into a critter or eggliner would be no easy task. If you want more axles to pickup power, you can add a trailing car with "live axles" and a jumper wire to the engine."

BTW, to the original poster, back on March 4 of this year I posted a thread with pictures for a small flat car that could be pulled behind the Accucraft railcar or even the MDC/USA speeder that had wheel pick-ups and a jumper to the railcar and speeder just to get over insulated frogs on my layout. The thread should be in the archives, but I've not been able to access it.


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## SteveC (Jan 2, 2008)

Here ya go Todd

Traditional Power Forum/Topic: New "Power Wagon" for Small Two-Axle Motive Power[/b]


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## toddalin (Jan 4, 2008)

Posted By SteveC on 07 Jan 2011 06:29 PM 
Here ya go Todd

Traditional Power Forum/Topic: New "Power Wagon" for Small Two-Axle Motive Power[/b]




Thanks Steve.


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## PSLIMO (Jan 4, 2011)

Hey Guy's,

I really appreciate the input and followed up on all the posts.

A big thank's to "toddalin" for help on the bipolar capacitor array link. An even bigger thanks to David who has the website on these issues. A couple of emails to him and I was good to go.

In short, I started the project with 2 very small 4700 uf capacitors and 2 diodes... That's it! Initial testing was very encouraging and at higher speeds it eliminated the light flickering as well as the jerky performance of the Eggliner.

At slower speeds it had no problem getting passed the frogs. Without the voltage robbing lighting it could crawl across them. Time to ramp it up with larger capacitors. I might even replace the lighting with LED's.

Phil


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