I’ve got my antique Bachmann GP40 converted to DCC and running like a dream. I didn’t know if I’d be able to, being that it’s what I call an ‘old school’ locomotive, with the motor grounded directly to the frame. It was easier than I thought it would be. The piece that the motor grounded to was just a thin metal tab that stuck up from the frame. All I had to do was break it off. From there it was a simple matter of just soldering a ground wire to the motor and soldering the other end to the decoder. From there, everything else was a snap. After about 20 minutes, I had the decoder wired. I put the locomotive on the programming track, sent a command to it and it responded. From there, it was to the main line, where it performed flawlessy. Before the conversion, it had no crawl capability and ran like a scalded ape. Now it’ll crawl with the best of them and runs at a believable speed. My oldest locomotive (30 years old) is now a DCC runner. I also swapped out the old GP40 shell for a GP40-2P shell that I had laying around, just to update it a bit. Maybe some day, I’ll get around to putting a can motor in it and get rid of the old open frame motor that’s in it now. But as long as it works, it’ll stay in there.
I’m close to being into dcc and have two hobbytown units I’ll want to do one day, rs3 and geep chassis under tyco gp-20 shell; sounds a lot like your older bachmann. glad I saw your note, inspiring it is. I’ve already got the motor isolated on the gp frame, mounted it in some caulk to cut down vibs, does ok with one brush to rail and the other brush gets juice from a wire captured under the motor frame. might just work. take care. have fun!
Jeffery,
The older (black box) spectrums are made like that. They use a split frame and ground both poles of the motor to the frame. The lighting circuit board has two prongs, one touching each side of the frame, for power. They also have the small metal tabs which must be removed to convert to DCC. The good news is the can type motor is otherwise electrically isolated from the frame.
I converted a Dash 8 40b without problem and will do a DD40AX next.
Tilden
My old Bachmann’s frame is very similar to that. I think what you’re describing is a frame with a left half and a right half. This one is also two pieces. A lower half and an upper half. Only the lower half had a tab connecting to the motor. The upper half was connected by a wire. It looks very similar in appearance to the Bachmann units that are out now, but with a drive similar to Athearn. Keep in mind that this unit was made in Germany and not the US, Japan or China. I’ve seen very few like it. Here’s a pic of the mechanism.
If I understand your physical limitations, Jeff, I applaud you for trying this venture. I am sure it gave you immense pleasure to have succeeded. Well done!
Thank you, Selector. You’re right. What’s easy for most can be difficult for me. Just doing a simple soldering job can be hard. Try soldering something when you’re shivering and you’ll get the idea.
Yes Jeff, the frames do have a left and right half. Nice pic on the conversion. A lot of time those frames do not leave much room for a decoder. The conversion works out well though. Now that I’ve got the Toby and Spencer conversions out of the way I’ll tackle that DD40.
Also, I think I’ve got your Bachmann beat. I converted my first train engine, a 1959 (when I got it for Christmas) Mantua 0-4-0 switcher to DCC. Used a DZ123 decoder and added lights. (Of course, I had already replaced the original open frame motor with a Helix Humper, so that might be considered cheating).
Tilden
Good for you Jeff keep up the great workmanship
I’ve decided I’m going to pitch the open frame motor and replace it with a Mashima motor. Of course I’ll have to remove the flywheels from the Mashima, as there’s no room for them in the Bachmann frame. Should take me about two hours.
It’s done! I had planned on using a Mashima motor but couldn’t find one in my parts box. I did however find a PPW motor that I had gotten to remotor a 4 axle switcher, which I never got around to doing. Removing the old open frame motor was easy enough. It was getting the can motor to go in that was the tough part. It took a little grinding, a little coaxing, some kind words and some glue to get it place, but it’s done. It’s a shotgun wedding if ever there was one, but it’s a 300% improvement. The locomotive used to hitch (jerk) when going from low speed to high speed. No longer. Now it’s a smooth acceleration from low speed to high speed. And it’s much quiter. Before it sounded like a small pepper mill. Now it’s almost silent.
Great news Jeffrey nice when things work out.
Jeffery I am happy you got it to work. That is a challenge I would not have tried. Well done!
I thrive on challenges.