want to add a DCC decoder to an engine where one motor brush is not insulated from the frame. Would like to figure out how to isolate it from the frame. I recently bought the engine, a Reading I-10. It looks like someone did a nice job adding a gearbox and replacing the motor.
Does anyone know what model motor this is?
the following photo shows the motor and the insulated brush with a yellow wire soldered to tab (there's a single strand from the black wire as well). (Click the photos for a bigger image).
the other side shows the other brush and a non-insulated screw near the bottom of the motor into a copper plate between the motor and magnet. I need to isolate this from the frame. I believe the other side (above) has some insulating plastic. I assume I'll have to take the motor apart. I do have some plastic screws.
another, more common motor has the brushes isolated from the frame. This is not that type of motor.
another option is to replace the motor. I have another that could probably fit, but there's probably even more effort to figure out how to mount it by either making a bracket or drilling and taping a hole in the motor to use this existing screw.
greg - Philadelphia & Reading / Reading
If you can't isolate the brush, I would use some automotive grade RTV and use that to reattach the motor to the frame.
Jim
What make is the model? That will probbaly help identify the motor. Looks like a knockoff varient of a DC-71. Not nearly as easy to isolate that brush as a DC-71 though. Also, if it's fairly old, the magnet is probably weakened and it will draw too much current.
That can motor there, you can attach with RTV. Might need to make some sort of angled wedge piece that you would screw tot he loco using the existing motor scre, then RTV the can motor to that. I see 23:1 on that motor - does it have an internal gearbox? Might be too slow, combining the internal gearbox with the one on the loco.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
+1 on the RTV
Or
Caulk does amazingly well as a way to hold the motor in place and to isolate it at the same time. I like caulk because it's easy to yank the motor up with a #11 Xacto incase you have to replace it.
Quality can motor replacement motors can be obtained from Micromark and NWSL.com
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
On brass steam that I've installed DCC in with motors like that, the motor was held to the chassis from the bottom with two screws into the frame of the motor to act as the ground points. Use an insulated washer between the motor and the chassis and replace the metal screws with plastic ones. You can then utilize any one of the screws in the motor's frame to act as the grounded brush contact point.
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
rrinker What make is the model? That will probbaly help identify the motor. Looks like a knockoff varient of a DC-71. Not nearly as easy to isolate that brush as a DC-71 though. Also, if it's fairly old, the magnet is probably weakened and it will draw too much current. That can motor there, you can attach with RTV. Might need to make some sort of angled wedge piece that you would screw tot he loco using the existing motor scre, then RTV the can motor to that. I see 23:1 on that motor - does it have an internal gearbox? Might be too slow, combining the internal gearbox with the one on the loco.
Both models pictured are imported by Gem. Other models from Gem are manufactured by Olympia and have different types of motors.
I had thought of using Kaptan tape between the motor and frame and using a plastic screw to hold it in place. I hadn't thought of using some sort of glue.
thanks to all for the comments
Greg.
Look for a Bowser DC71 with the scewed armiture and replace the magnet with super amgnets. It should be a direct replacement for that motor. A KTM open frame is another choice. Why risk frying a decoder for a cheap motor? I have seen the DC71 and KTM motors sell on Ebay for under $10. K&J magnets has the super magnets for another $2.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
locoi1saLook for a Bowser DC71 with the scewed armature and replace the magnet with super magnets. It should be a direct replacement for that motor. A KTM open frame is another choice. Why risk frying a decoder for a cheap motor? I have seen the DC71 and KTM motors sell on Ebay for under $10. K&J magnets has the super magnets for another $2.
i replaced the magnets on my other locomotive with super magnets. I assume i can do the same with this one.