DCC Conversion Project

[richd286]

I bought an FT-B loco at a super price that would complete my SF Super Chief prototype.  Missed the fact that it was a DC version and teaming that with my DCC FT-A was not going to work.  I also have a decoder I got a while back... so 1+1= a challenge.  My first DCC conversion.

Step 1:  Open up the FT-B and see what the connections look like.  The loco shell came off easy.

Step 2:  Observed the black (-) wires, one coming from each truck, soldered to the top of the motor.  Clearly the appropriate decoder wires will come between that connection.  Easy enough.  The schematic shows the (+) connections down by the trucks, so the trucks needed to be separated from the chassis.  Done.  The drive shafts dropped away easily and I hope getting them back in someday will be as easy.

Step 3:  No (+) wires... Ahh the (+) in the schematic are really spring clips connecting the power pick up to the metal chassis.  The metal chassis is the heavy metal block that occupies 90% of the body cavity and gives heft to the model.  I have read enough to know that in some conversions when the chassis is part of the connection it has to be isolated,  Hmmmm how will I wire the decoder to this?  Clearly the spring clips have to go and a new lead from both trucks needs to be wired to insert the decoder into this portion of the circuit.  Quickly approaching the limit of my knowledge.

Knowledgeable people can pitch in at any time....

[Lt Dan]

I just converted one of my son's newer Bachman DC engines to DCC, it is fairly straightforward.

If you had photos that would be helpful, but here are my suggestions:

The black wires from the trucks need to be tied together with the black wire of the decoder. The red wire of the decoder needs to either be tied to the chassis or you need to isolate the chassis from the trucks and run wires from the trucks (as you mentioned)

If you make sure the decoder and wiring is electrically isolated from the chassis you should be able to simply drill a hole in the chassis in a convenient location and solder your red decoder wire to it.

You will then need to run a black wire from the motor to the decoder (usually the gray wire). I'm assuming there is a red wire from the chassis to the motor, if so, you'll need to disconnect it from the chassis and connect it to the decoder (usually the orange wire).

The remaining wires will be for lighting effects/sound/etc.

[richd286]

It works!
I read as much as I could on the topic.  It was a very straight forward upgrade.  The decoder tells you which terminal to solder to which color wire.

I bought some thin wire that I thought would be fine, and even then the wires in the locomotive and coming from the decoder are very fine and the wire I bought thicker, so I should have bought the finer wire gauge.  Thinner wirewould have made the clearances within the chassis easier to work.

Thanks Lt Dan

Now I have a 20 year old proto 2000 BL2 that need to come into the future.

[Jim Banner]

richd286,

I sound like the locomotive you converted might have been an Athearn.  The Proto 2000 BL2 looks just like an Athearn once you get the shell off.

I am wondering if you tried "to simply drill a hole in the chassis in a convenient location and solder your red decoder wire to it." and if so, how you made out.  Personally, I have never had much success soldering to chasses and either drill and tap them, then attach a solder tab or simply drill them and stuff the wire(s) into the hole along with a tooth pick to tightly wedge them in place.

Jim

[richd286]

This conversion was just a Bachmann DC FT B and it went well.  I was more worried about my soldering technique rather than where the wires go.  I chose to avoid using the chassis and instead isolated the power from the wheels to the motor.  Runs so well that I had to program the CVs to slow the initial accelration to match my store bought DCC FT A.  I needed to speed match them in a consist for the maiden run of the El Capitan Super Chief.

I actually have two DCC project pending:

First is a Maine Central switcher that has an 8 pin plug that was supposed to be simple enough.  HOWEVER upon reading the locos conversion directions I need to change out the headlight which I believe has too high a current draw.  Need to research that more!

My big challenge will be the old Proto 2000 BL-2.  I have test run it and replaced the axel gears ( Imagine! Cracked from day one when I bought it in 1991).  I will need another bare wire decoder and a plan for the lighting change that will be required.  More investigation. 

[jward]

cracked axle gears are pretty common on proto locomotives. many of the older ones use a drive that is based on the tried and true athearn drive. they are so close that in many cases the gears are interchangeable. since athearn axle gears do not have a reputation for cracking like proto and kato ones, i'd look into getting a few athearn gears if you can find them, or buying an old athearn for dirt cheap at a train show, and using it as a parts source.