# Bachmann Davenport



## nkelsey (Jan 4, 2008)

Christmas came early and the man in brown delivered my Davenport switcher yesterday. Is anyone (TOC you listening) aware of any issues with the Davenport before I start conversion?


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## East Broad Top (Dec 29, 2007)

Check the wires from the track pick-ups to the control board. On my sample, they're undersized for the current that could potentially be drawn through them. (See the review in the December '08 _Garden Railways_). If you're doing DCC, I'd be tempted to beef them up a bit just to be safe. I'm not sure what effect undersized wires have on DCC signal integrity, but I seriously doubt it's a beneficial attribute. If you're running regular track power under light loads, I wouldn't worry too much. It's not hard to run new wires just to be safe, and if you're wiring sound or plan to use the smoke, it might be a good idea. If you're converting to battery power, this is a non-issue. You'll chuck everything inside anyway--not that there's a whole lot to begin with. Good luck fitting batteries in there. I'd look to a small LiIon pack for maximum use of space. 

If you are running track power, make sure the pick-ups stay in contact with the back of the wheel. On mine, they did, but some wiggling of components during my inspection showed that _if_ the pick-up assembly is moved as far inboard as it can possibly go _and_ the wheels are moved as far outboard, then there may be a gap just large enough to break contact. That's a big "if," so it's not something I'd particularly worry about. It would have to happen on both axles at the same time for pick-up to be interrupted. The gearing appears sturdy, and both axles are powered, so you don't need to worry about loose counterweights or things of that nature. All the screws on my sample were snug. 

Later, 

K


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## SlateCreek (Jan 2, 2008)

Interesting. I'm reading this after just unpacking mine, which arrived about an hour ago. 

Here are a couple of impromptu photos (as in, on the desk where I'm typing....) just for fun. 


















Mine will be going to NWRCS for conversion into a DAVEnport, once I move the grabiron supports off the radiator to the frame where they belong, install a rear headlight, and a new front headlight that's a bit more reasonable. It'll also get graphics to be Slate Creek #2, and probably a horn and a bell or something. 

I'm also kind of concerned about the seat in the cab -- especially as a big guy, it concerns me that if you were really a 1:20.3 fellow (and not just the itty bitty Sherman Pippin that comes in the Annie) you'd have a lot of trouble sitting on the itty bitty seat in the cab, and even if you did there'd be noplace to put your feet! I'm thinking something larger, and probably hinged to the back wall of the cab.... the "transmission hump" is so large, I can't see much else working. 

But, overall, it's a solid little guy. I'll be interested to see how it runs. 

Matthew (OV)


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## wchasr (Jan 2, 2008)

I saw there at Ridge Road last weekend but wasn't able to truly look them over. Not near enough time. Next trip I'll plan better and take more time there. 15 minutes in that place was barely enough to make ANY purchases! I was not impressed by the price though. (sigh) 

Chas


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## nkelsey (Jan 4, 2008)

Thanks, mine will be converting to RC/Battery so I guess its cut and chuck.... May not put sound in this, may be tough getting just he batteries and airwire card in...Nick


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## stevedenver (Jan 6, 2008)

my, what a large head light!


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## vsmith (Jan 2, 2008)

Posted By stevedenver on 10/28/2008 4:56 PM
my, what a large head light! 


..the better to see you with, my dear.


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## TonyWalsham (Jan 2, 2008)

Looks like they had a bunch of big headlights left over in the parts bin and used them instead of something more aesthetically pleasing.


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## nkelsey (Jan 4, 2008)

Yeah, the headlight will be changed...


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## snowshoe (Jan 2, 2008)

Posted By wchasr on 10/23/2008 12:31 PM
I saw there at Ridge Road last weekend but wasn't able to truly look them over. Not near enough time. Next trip I'll plan better and take more time there. 15 minutes in that place was barely enough to make ANY purchases! I was not impressed by the price though. (sigh) 

Chas

The prices in the store are more then if you bought them on-line. I remeber ordering a few things from them but had trouble with my internet. I ended up calling them. When I got done they gave me the price and it was more then what the internet said. I mentioned that to them and they said that they made a mistake and gave me the store price and ot the internet price.


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## stevedenver (Jan 6, 2008)

so-how does it run? 


heavy?


pulling ability?


stalling issues?





how is the quality and plastic etc?


any goodies likes tools, engineer, etc included?


cool looking little loco





tell us all about it


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## East Broad Top (Dec 29, 2007)

It runs well. Smooth, quiet, and speeds well suited for battery power. 

4 pounds; 

around 1 pound drawbar, pulled two Accucraft passenger cars up a 4% grade--slipping, but it pulled 'em. (Accucraft passenger cars aren't known for easy rolling) 

short wheelbase, so be careful on long frogs; 

Good quality plastics, crisp details; 

No goodies. 

_Garden Railways_ review: http://www.trains.com/grw/default.aspx?c=a&id=1161 

Later, 

K


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## Road Foreman (Jan 2, 2008)

Kevin, 

Where is the DCC plug?? I do not see a 8 pin plug on the board.. 

BulletBob


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## SlateCreek (Jan 2, 2008)

I'm not Kevin, I know! 

The DCC plug is in the very corner of the board.... it's designed so that a small 8 pin decoder would plug in there, and the decoder body would snap into the big metal clip right next to it (much more visible on the board.) It comes with some kind of dummy plug inserted in it reminiscent of some of the HO stuff I've seen. 

I have the board on my desk at home, having removed it ... I'll put a close up photo up tonight if you'd like. 

Matthew (OV)


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## Road Foreman (Jan 2, 2008)

Matthew (OV), 

Yes, I would like to see a picture of the socket & where it is on the board.. 
Thank you very much.. 

BulletBob


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## East Broad Top (Dec 29, 2007)

In the photo on the GR review, it's the small board between the two plugs on the upper left part of the board. 

Later, 

K


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## Road Foreman (Jan 2, 2008)

Kevin, 

Thanks, I see it now.. 

BulletBob


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## SlateCreek (Jan 2, 2008)

Here's not the best you'll see, but it's large. 










Matthew (OV) 

PS. note the dummy plug which I've removed and set just below the socket it fits into, on the table.


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## Tom Lapointe (Jan 2, 2008)

Hmmm- the "Force" must be strong with this one!









Looking forward to getting one of these myself, just have to decide what color scheme (leaning towards a green one).








Tom


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## SlateCreek (Jan 2, 2008)

LOL ... that's about as close as I can get with that particular camera and still have any kind of focus. (It's old... REEEALLY old.... has a 3.5 floppy disc drive in it!) 

The mouse pad was originally there to get enough tilt to remove glare... I didin't even really notice how the dark side of the Force had showed up until afterward! 

Matthew (OV)


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## East Broad Top (Dec 29, 2007)

Here's a close-up of the circuit board. Not much to it, really. The DCC plug is in the upper left, shown with the "dummy plug" installed. You can see the difference in size between the wires coming from the track (the brown and black pair) as opposed to the wires going to the motor and LED (red and black). It's almost as if they--literally--got their wires crossed, installing the smaller socket intended for the LED connection where the track pick-up was supposed to go. There's no reason for wires going to the LED to be that heavy, and they are smaller in other locos. Moot point if you're going battery. 









Here's the loco next to a B'mann 1:20 box car. It's comparatively a small little critter. 









While not a Davenport, this is a (shaky) shot of the cab of the EBT's M-4, a diesel mechanical critter that's about the same size as the Davenport. 









Another shot from the other side, showing the engineer's seat, and showing the air tank and what I believe is the transmission transfer case or somesuch below it. 

Later, 

K


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## Road Foreman (Jan 2, 2008)

Matthew (OV) & Kevin, 

Thanks for the pictures.. They are just what I need.. Will be installing a HO decoder & may be a Digitrax DH165xx with the "SoundBug" decoder.. Again thanks!! 

BulletBob


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## East Broad Top (Dec 29, 2007)

Make sure whichever decoder you buy has a minimum rating of at least 1 amp, higher would be better. At slip, without smoke, the loco draws .8 amps. Stalled, it drew over 2 amps. Turn on the smoke and add sound to that, and you're increasing your current draw even more. I'm not familiar with the whole gamut of HO decoders, but a sampling of the ones I saw at Caboose the other day were around .5 to .75 amp capacity. 

Later, 

K


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## Road Foreman (Jan 2, 2008)

Kevin, 

A lot of Digitrax decoders are 1.5 amp / 2 amp peak.. Will get 1 of those & try it.. I hope 1 that can have the "SoundBug" added will fit.. It looks close.. May have to double the socket to get the clearence.. Again thanks for the pictures.. 

BulletBob


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## StanleyAmes (Jan 3, 2008)

Posted By East Broad Top on 10/31/2008 8:33 AM
Make sure whichever decoder you buy has a minimum rating of at least 1 amp, higher would be better. At slip, without smoke, the loco draws .8 amps. Stalled, it drew over 2 amps. Turn on the smoke and add sound to that, and you're increasing your current draw even more. I'm not familiar with the whole gamut of HO decoders, but a sampling of the ones I saw at Caboose the other day were around .5 to .75 amp capacity. 

Later, 

K

Kevin

If you use one of the more modern decoders than 1 amp motor drive decoder is likely more then sufficient. 

Most modern decoders use a high frequency motor drive and as such the stall current is not really relevant. I am using a 1 amp continuous rated decoder with absolutely no problems. I would recommend overload protection on the decoder should something happen in the future but manu modern decoders come with this as a standard feature.

After reading your article I also checked out the wiring to the rails in mine. The wire they used in the locomotive is actually larger then the wires used in most 1 amp decoders. True they are much smaller then in most large scale locomotives but the amp draw of this one is more in line with HO locomotive current draw.

I run mostly steam but I decided to get one for yard duty and it seams to work very well.

Stan Ames

www.tttrains.com/largescale


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## Crosshead (Feb 20, 2008)

Posted By StanleyAmes on 10/31/2008 6:30 PM
Posted By East Broad Top on 10/31/2008 8:33 AM
Make sure whichever decoder you buy has a minimum rating of at least 1 amp, higher would be better. At slip, without smoke, the loco draws .8 amps. Stalled, it drew over 2 amps. Turn on the smoke and add sound to that, and you're increasing your current draw even more. I'm not familiar with the whole gamut of HO decoders, but a sampling of the ones I saw at Caboose the other day were around .5 to .75 amp capacity. 

Later, 

K

Kevin

If you use one of the more modern decoders than 1 amp motor drive decoder is likely more then sufficient. 

Most modern decoders use a high frequency motor drive and as such the stall current is not really relevant. I am using a 1 amp continuous rated decoder with absolutely no problems. I would recommend overload protection on the decoder should something happen in the future but manu modern decoders come with this as a standard feature.

After reading your article I also checked out the wiring to the rails in mine. The wire they used in the locomotive is actually larger then the wires used in most 1 amp decoders. True they are much smaller then in most large scale locomotives but the amp draw of this one is more in line with HO locomotive current draw.

I run mostly steam but I decided to get one for yard duty and it seams to work very well.

Stan Ames

www.tttrains.com/largescale





Stan,

I'm intrigued.

You say: "If you use one of the more modern decoders than[sic] 1 amp motor drive decoder is likely more then[sic] sufficient."

You also say, to explain this that: "Most modern decoders use a high frequency motor drive and as such the stall current is not really relevant."

Assuming that's true, I wonder why they have a rating attached, like "1 amp continuous" or why they'd "recommend overload protection on the decoder should something happen in the future" and why "many modern decoders come with this as a standard feature." If the current isn't really relevant, why worry, and why bother? And, why make some decoders capable of handling so much more? 

As I recall, USA Trains, arguably the most current hungry of them all, often operate quite well on Aristocraft PWC, which is a form of "High Frequency Motor Drive" and I bet the 1 amp rating of your standard 1 amp decoder would, if used in such a locomotive, become quite relevant!

Finally, isn't the operative question not "Are the wires in the locomotive larger than the ones on most 1 amp decoders," but "Are the wires in the locomotive capable of handling current beyond 2 amps, since at full slip with smoke and sound working, it might be expected to handle that much?"

I am glad that you've found the engine meets your needs with a 1 amp continuous decoder. Hopefully conditions in your yard will not tax it beyond that, so that you may continue to enjoy "no problems"

With my compliments,

Richard C.


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## Curmudgeon (Jan 11, 2008)

Ah. 
Stall current over 2 amps as tested. 
When shiny wheel plating goes away and tractive effort increases, you are saying the one-amp coninuous will be just fine. 

Lordalmighty, I am glad someone quoted that. 

Now we're back to that "special current" you've been on about.


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## TonyWalsham (Jan 2, 2008)

Aaaaaah!!! Stanley. 

What a guy!


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## Greg Elmassian (Jan 3, 2008)

Well, I have to weigh in for a bit. 

First "1 amp decoder" is a meaningless phrase. "1 amp continuous" or "1 amp stall" means something. 

You can probably draw 2 amps at stall plus the smoke unit (maybe 1/2 amp) plus a sound decoder (about an amp, let's say)... so you could draw 3.5 amps continuous. So your wiring should not have significant loss at that current. I think that the wire supplied is not up to the job... It may be fine in the stock loco, but don't add sound and don't run it at max load with the smoke unit on. 

OK, now I am confused about the statement: "Most modern decoders use a high frequency motor drive and as such the stall current is not really relevant." 

I don't get this at all. Is this saying because the PWM is high frequency, the current used is less? I think I know where this might have come from. 

If you are going slow, you get higher voltage and less current in PWM as opposed to analog. This is because PWM is ALWAYS at full voltage. That makes sense. 

At full load, with full speed (which is the way you should design your installs, to be bullet proof), then the PWM is "full on" and you have full analog DC voltage to the motor. 

So I can understand a statement like "at low speeds PWM uses more voltage and less current to a motor" 

But we are talking a quality installation here, I hope, not one that runs ok when going slow, and melts wires at high speeds or loads. 

Regards, Greg


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## Road Foreman (Jan 2, 2008)

Kevin, 

What size is the track wire?? Looks to be about 22 gage.. If it is 22 gage wire then the maxium amps is 7.. This would be plenty good it looks like to me.. 

BulletBob


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## Curmudgeon (Jan 11, 2008)

Look at the "Con2 M+M-" plug. 
Granted, you can't tell with Bachmann and insulation size. 
Seen some that LOOKS good from insulation OD, but cut it back, and you might be surprised at what's inside. 
Now, compare the diameter of the insulation to that in the "Con1 L-R" plug. 

Now, looks like Con1 is track. Looks like Con2 is motor. 
Looks like track is about half the OD of motor.


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## East Broad Top (Dec 29, 2007)

Bob, the wire measured out on the order of 28 gauge or so. It is most decidedly smaller than the 24 gauge wire spools I have in the workshop. If you look in the closeup photo, you can see where I peeled the insulation back to expose the wires themselves. The wire going to the motor and headlight measured at around 24 gauge. 

Later, 

K


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## Curmudgeon (Jan 11, 2008)

Maybe that's a design criteria, Kevin. 
You know, a built-in fuse. 
Kinda like what Stanley was telling us about the 3-truck circuit boards. 

Funny thing about radio/battery.........never have to worry some assembler (or consultant) hasn't used super-small wire or worry about pickup springs and contacts.....


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## paintjockey (Jan 3, 2008)

Kevin, in your photo at the top of the page, I don't see the DCC plug. I see the 8 holes in the board with solder between 2 sets of 3 holes, but there is no 8 pin socket there nor a dummy plug. I may be wrong, and please correct me if I am, but did it come this way? Or is that a loaner model B-mann sent to you without the plug? In slate creeks picture the 8 pin socket is in the lower right corner, with the dummy plug removed, your board doesn't look like that. Really, I'm just curious. 

Terry


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## SlateCreek (Jan 2, 2008)

(Still not Kevin, I know) 

In Kevin's photo, the dummy plug is still installed, and you're looking at the bottom of it. It's there, toward the top left of the photo, between the brown/black track pickup plug and the red/black headlight plug.... you can see it says "ROHS" on it or something, and is hard to see because it's the same color as the board behind it. 

I removed the dummy plug from the socket in my photo to make it a little easier to see.... otherwise it's the same thing. 

Matthew (OV)


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## paintjockey (Jan 3, 2008)

Yup, your right. I was looking at it last night with some tired eyes and couldn't tell it was there. It looked like part of the board. My apologies.


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## Road Foreman (Jan 2, 2008)

paintjockey, 

Welcome to my club!! I could not see it either.. Had to have it pointed out!! 

BulletBob


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## Guest (Dec 25, 2008)

running light, 0.5 amps, full slip, 1.4 amps, full stall, 3 amps. This is at 20 volts. 

This is a little heavy for an HO sized decoder, maybe it would work, maybe not. 

Anybody put a decoder into one of these puppies yet?


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## chaingun (Jan 4, 2008)

Just received and put into service my first (last?) Davenport. I was initially impressed with the construction and detail. I wired it for battery operation and put it to work. I was stunned when I found out it has the same flaw (with a single power truck) as do the two truck Shays! This flaw is - when going down hill (2-3%) the power train binds up releases, binds up release … etc. I won’t go into this as the Shay problem has been beat to death here on MLS and if you are interested I am sure you can locate a lot of it in the archives. 
For its size the little sucker is a good puller on flat ground or up hill. 
Best, Ted


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## Guest (Dec 30, 2008)

yep, on a steep enough grade, it does surge, see 

http://www.girr.org/girr/tips/tips10/davenport_tips.html 

h.264 video 

http://www.girr.org/girr/tips/tips10/Davenport.mov


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## East Broad Top (Dec 29, 2007)

I just double-checked mine, and noticed no surging at all on grades up to 8%. I tried running both ways, with and without a load, running on as little as 1.5 volts (a single AA battery). I'm not disputing the above experiences, just offering that they may not be representative of the whole. Why one does and one doesn't, I can only chalk up to the vagaries of mechanical design. 

Later, 

K


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## SlateCreek (Jan 2, 2008)

Yeah, but you know, having ridden in something similar.... the PROTOTYPE surges on grades.... even with a hydraulic clutch! 

I should have some "finished" photos of mine in the next week or so, I'm just finishing up the final 12 details or so. 

Best, 

Matthew (OV)


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