I’m in the midst of a kit bash and have hit a stumbling block. My motive power for this bash is a Bachmann Gandy Dancer. But I need to install a decoder on it. It will all be hidden so nobody will see the wiring or decoder. But how can I make the connections? I’ve never tried anything but a plug-and-play so I’m a bit lost here. Anyone tried this before with any success?
I doubt you have any room in there but Digitrax and TCS both have tiny decoders good for Z, N and HO scale… The decoders are about the size of a dime and quite thin. Usually good for 1 amp. I am using a Digitrax DZ125 in a Mantua 0-6-0T. Check with online DCC sellers. They show the size of the decoders.
I suspect the inside is all motor like the tender of the Bachmann John Bull which I have. No room for a decoder in the John Bull tender.
The Dancer looks like the size of the John Bull tender. Not having that thing, it is just a guess. Track pickups are going to be a real pain.
Rich
This one may indeed be Mission:Impossible (the original, not the horrible Tom Cruise movies). There are some fairly large photos of this model (larger than actual size) on the internet and it looks like other than the two yellow side plates, the entire middle is the motor. The floor is thing, and I don;t see there being any room underneath with the motor gear in the middle and gears on each axle.
I wouldn;t sya anythign is too small, not after seeing the scratchbuilt N scale steam locos a friend of mine has made and installed decoders in - slopeback tenders, tender drive AND the decoder in the tender. He used a CT Elektronik decoder, it makes the DZ125 look huge. Even so I don’t see how you could hide this and the wires in that Gandy Dancer. You’d have to repalce the motor with something slightly smaller and mount the decoder right on the motor. Good luck getting a diffeent motor AND getting the gears to work out.
–Randy
A TCS M-1 or Lenz LE077FX, both of which are smaller than a dime, are what I have used. You must know how to solder delicate electronics and have a soldering iron with a very small tip.
I guess I was not really clear in my original post. The motor assembly will be completely hidden under a boxcar sized “hat”. So the motor and decoder will be hidden from view all the time. The size of the decoder will not mater. But I don’t see where to solder the wiring. As I stated earlier, all I’ve done are plug-and-plays so the soldering is intimidating to me!
Soldering’s fairly simple.
In general;
- If the join is a dull metal colour, it’s not good - should be reflective
- The best method is to hold the the solder to the two items to be soldered, and just touch the soldering iron to them. Once the solder starts to flow, back off.
I’d suggest getting some scrap PCB and wires and practicing until you feel confident.
With hardwired DCC installs:
Red & black wires go to track pickup
Orange and Grey go to motor.
White and Yellow go to the front and rear headlights (can’t remember which is which off the top of my head) with blue as the return, IIRC. These should be listed in the instructions for your decoder as well.
Hope this helps,
tbdanny
I have one of these somewhere, it disappeared into a box long ago when I went DCC so has not been run in ages. But as I remember, this thing has a split frame. The conduction path is from the wheels, to frame to motor. The motor pickups as I recall, sit up on top of the motor, somewhat in view between the two men. To convert this to DCC, you are going to have to figure out how to get the split frame apart.so that you can isolate the motor contacts. The goal here is to break the conduction path from frame side to the motor. I would use an Ohm meter to ensure that the motor is fully isolated. Once you have accomplished that, then it is a simple matter of connecting the decoder. Red and black wires, one to each frame side, orange and grey to the motor contacts. Since it is going to be hidden, it does not have to be pretty!.
I found my GD and it does not look like it will be hard at all. The motor contacts are indeed right on top and exposed. There are small metal pieces from the motor contacts to each the frame. These are the conductors. If you remove them, then you can solder your motor wires (grey and orange) directly to the motor contacts. I would then prep and solder the red and black track pick up wires right onto the frame sides. Looks fairly straight forward and not a difficult soldering job. Your biggest problem may be getting good solder connection to the side frame. It may even be worth tapping in a screw and doing it that way?
Everything you stated above makes sense. Finally I get it! What about isolating the motor as someone else posted? Isn’t the motor already isolated since it’s in the plastic housing?
If you have an Ohm meter you can check. Once you have removed the wires that connect the frame to the motor contacts use the meter to see if there is any conduction between the motor contacts and the frame. You want to see infinite resistance (ie no conduction) Somehow I doubt there will be a conduction path, but I always like to check myself to be sure. It is a 2 second test that can save a problem if things are not isolated. I agree that the plastic film around the can of the motor almost certainly acts as an insulator.
Thanks for the response. I have no clue what you are saying, but thanks. I have alot to learn. I may need to find my local electrician to help me out here!
Not to discourage you but you should get a multimeter and learn how to use it if you are going to mess with DCC. P Lug and play is a different issue. This is where you are working at component level.
Below is a diagram I found for the Dancer. It “appears” that the motor brushes are connected to side frames that i think “might” be metal.
With a ohm meter, there should be no continuity between the motor brushes and the wheels, i.e. motor brushes isolated. Red and black decoder wires to left and right wheels. Orange and Grey to motor brushes. Standard NMRA wiring colors.
Do a Google search for dcc decoder wiring colors. It sounds right now you do not know much about DCC decoder wiring.
http://www.hoseeker.net/assemblyexplosionbachmann/bachmanngandydancerpg2.jpg
Rich
http://www.hoseeker.net/assemblyexplosionbachmann/bachmanngandydancerpg2.jpg
It appears the motor occupies most of the inside. Pickups will be very iffy with this style of mechanism. The John Bull motor in the tender is similar. I had to take apart the mechanism and clean off all the corrosion and apply a thin film of electrical contact cleaner and corrosion inhibitor.