# Need help with B unit speed/power issues



## Bluemill (Nov 26, 2012)

American Flyer models 466 & 467 counterfeit 

I have put a great deal of effort into making a counterfeit model 467 Alco B unit for the Comet locomotive set. Our first train in the family was a 466 Comet with the coaches given at Christmas 1954. I have redone the body shell on a completely stripped old Silver Flash B unit, repainted it silver and Comet blue, put on the decals, pinstriped it, and sealed it. 

I had a very good tech do the electronics, including a new speaker, diesel roar, and a new diesel horn generator. That 1954 technology is so poor, that I've opted to disconnect it, for I thought that it was robbing too much power from the motive motor, to the point that speed was cut in half. The diesel roar isn't bad, but it appears to be taking a lot of amps/watts, and the fall off of speed is equal to a 50% drop.

When you press the diesel horn generator the lights all brighten and the train actually goes a little faster, so it's also not very impressive.

However, the body is still nice, and looks good with the rest of the train. I decided to unsolder all of the electronics so as not to cut into the speed performance. This made little difference in speed, if any. It still is very slow. Physically, it is a lot heavier than a passenger car, but I did lubricate the wheels, and it appears they roll freely, although it does have sprung contact pads on each truck that might add friction and slow things a bit. 

I had another theory, the fact that all wheels are metal, makes me wonder if they are still absorbing electricity- or is it a simple case of a metal heavy car and too much friction?

Any help on this would be appreciated. The train without the B unit is the fastest of a fleet of 8 locos. With it, it's the slowest, the fall off of performance is that pronounced!

Best, 

Bluemill


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## flyernut (Oct 31, 2010)

My guess is the b unit is adding a lot of weight to the a unit. I had a b unit without any guts in it and it was a heavy beast, and I no longer use it. It had a home made chassis in it. For electrical issues I would contact "GunrunnerJohn", here on the forum. In my opinion, he's a wizard. Is the a unit a single or double engine unit?


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## tjcruiser (Jan 10, 2010)

Not sure how to speed up the B, but you could slow down the A to match, if desired...

Wire a few pairs of diodes into the A power feed ... each pair in parallel, in opposing directions, then a string of pairs in series. The diodes with induce a power drop, essentially castrating the A a bit, to the point where it can be a better match for B.

But castration is a nasty word 'round these parts ... 

(John, if you see this, please correct my electro-logic above, if need be.)

TJ


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## flyernut (Oct 31, 2010)

tjcruiser said:


> Not sure how to speed up the B, but you could slow down the A to match, if desired...
> 
> Wire a few pairs of diodes into the A power feed ... each pair in parallel, in opposing directions, then a string of pairs in series. The diodes with induce a power drop, essentially castrating the A a bit, to the point where it can be a better match for B.
> 
> ...


TJ, I believe the b unit is not motor-driven, just using power for the horn/roar.


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## tjcruiser (Jan 10, 2010)

Oh ... you could be right ... I've re-read the posts once or twice, and my head's a bit dizzy.

Then again .. I'm having a generally dizzy day ...

TJ


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## Bluemill (Nov 26, 2012)

*More details of the Counterfeit B Comet Alco*

The B unit is unpowered, but has trucks just like a powered Alco A unit, including metal wheels on both sides and sprung contact buttons, one on opposite sides of the two trucks .

The A unit is a single engine, "front wheel drive" loco. As a little guy, I used to pump more and more oil into it to make it go faster, and very soon it didn't work at all, so it got left on the siding, or the big train box. As a result, there is not a lot of wear, and it was run on the floor exclusively, i.e. it didn't fall off the table, so no serious wrecks. It's faster than a Plastic Pacific with a modern Can Motor conversion and Dalee e-unit, my answer to an AF hot rod. I have a big motor 326 Hudson that growls and is also very fast, but it can't touch the Comet. To have the B unit kill the speed is just too cruel after all the freaking work I've put into it!


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