Flakey power pickup, Forney

[scottychaos]

I finally got a forney! 
sound equipped..and she's a beauty! 

arrived with some damage..
one cylinder took a hit at some point in its long journey from China to me, was nearly broken off, but I was able to glue it back and straighten the piston rod..appears to be no lasting damage done..(I think..unless its related to issue described below..)

engine runs smooth, (when its running) sound working fine..
except the engine appears to be getting power ONLY from the tender truck!
no power pickup from the drivers at all..is that normal?
and when im testing the engine, sometimes the engine loses power..if I jiggle the tender truck, the power comes back on..

im sure its the tender truck causing the flakey pickup..other engines run fine on the test track.
I can lift the drivers right off the rails, and the wheels keep spinning, picking up power from the tender truck only..
however if I lift the tender truck off the rails, leaving the drivers on the rails, the whole thing goes dead..I have never heard of a model steam engine that doesnt pick up power from the drivers! 

oh..one other thing...I switched tender trucks! 
and..I never tested it with the original truck, because I didnt own a DCC system before I swapped trucks..
the wires to the tender truck appear to be uninsulated bare metal?!
how is that possible?
varnished wire or something??
im wondering if I scraped something loose when swapping trucks, and now perhaps im getting an intermittent short through those wires?

so..two odd things..(odd to me anyway!)
1. power pickup from the tender truck only.
2. tender truck wires, going to both rails, that appear to be uninsulated wire!

This is my first ever DCC engine..so maybe these things are  "normal" these days and I just dont know it! 

anyone one have any suggestions to make it run more smoothly?

thanks,
Scot

[morrisf]

The cracked cylinder is not unusual. Your fix is easier than sending it back.

There are pick up wipers for the drivers. For some reason, yours may not be either touching the back of the wheels or somehow got otherwise disconnected. Poke around the cover plate and/or trace the leads to find the break.

Morris

[morrisf]

Furthermore...

Remove the bottom of the ashpan. You'll find the various wiring connections under there. A red wire and a black wire run to the driver pickups.

There should be two wires of the same color to each terminal as follows:
Red to R
Black to L
Yellow to M+
Orange to M-
Blue to L-
Green to L+

The "bare" wire is enamel coated.

[scottychaos]

thanks Morris!
I thought those drivers should have power pick-up!
I will poke around, let you know what I find..

enamel coated??
hmmm..that seems risky to me..
whats wrong with good old plastic coating?
isnt it terribly easy for that enamel to wear off and cause a short?
looking at the wires, you cant even tell one is insulated..they both look like bare copper..strange.
but again, maybe this is some new technology that is actually perfectly fine and im just not used to it..wouldnt be the first time!

thanks,
Scot

[morrisf]

Actually, enamel-coated wire is a good selection for a fine wire that must be flexible, such as lead wires to a tender truck.

Enamel-coated wire is used in practically every electric motor. It certainly is not new.

If you've ever had to remove enamel coating to solder a wire to a terminal, you may have noticed that the coating is quite durable.

Morris

[scottychaos]

I fixed it! 

I took off the "DCC sound on board" cover on the bottom,
underneath is a bundle of wires..unscrewed the one screw holding down the wiring...one of the wires in the bundle had some damage..a small crimp..like something fell on it, sort-of smooshed..hard to explain.
I thought it might be smooshed enough to kill the power flow..so I jiggled it a bit, then put some electricity to the drivers..they turned!

just that small crimp in the wire was enough to kill all power from the drivers..
but now driver pickup is restored, and she's running smoothly! 

next step..major disassembly to see if I can convert her to On2..scary!
im not used to working with models that are so tiny!!

thanks,
Scot

[amdaylight]

Scott,

I e-mailed you from MLS wondering if you had tried to narrow this little monster down but never heard anything from you still wondering. From what I have gathered on the Yahoo On2 site it is possible but not easy.

Andre 

PS
My four Forney’s ran perfect straight from the box, If you have any problems I would send it back and get a different one no sense in having one with problems from the git go.

[renniks]

     Scott,

   The 'smooshing' may have broken the wire inside the insulation and your jiggle has pushed the ends together.  Vibration or a coupleof knocks could make them pull apart again. If there is any slack in the wire I would cut the squashed part,trim back the insulation and solder the ends together,covering the join with 'shrink'tubing. Don't forget to slide the shrink on to one end before you solder. Have done so myself before now when connecting lights to a DCC decoder. LOL

    Eric UK