Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
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.
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).
Good for you Jeff keep up the great workmanship
Lynn
Present Layout progress
http://cs.trains.com/mrr/f/11/p/290127/3372174.aspx#3372174
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.