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 Posted - November 11 2022 : 7:36:42 PM
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This is not so much a customization nor kitbash, but a set of repairs that reek of home talent. The MDC Boxcab is a nice locomotive in some ways, but it's not bulletproof. In short, some things just don't hold up. So far as I know, parts are not all that available, so the high art of jury rigging is needed.
I had one boxcab that worked quite well and got another at a bargain price, but it was not such a bargain. It lacked power and the motor overheated. At the time, I didn't know what that was about, and the engine languished on the sidelines. Later I found out that those symptoms mean a weak magnet. By that time, I also knew that you could get rare earth magnets in a variety of shapes and sizes. The picture below shows the motor with new magnets and a new lease on life:
Also, there was a flexible tube connecting the motor shaft to the flywheel, but it was inefficient enough that there was really no flywheel action. I took the tube off, and that let the gear walk off the end of the shaft, so I put just a short piece of tube on to hold the gear.
Each truck has a worm shaft geared to the axles, and that connects via a universal joint arrangement to a set of gears on the frame. The universal part that presses on the worm shaft splits after a while. Before putting on a metal ferrule occurred to me, I replaced one of them with something I cobbled up from plastic sprues:
On the left, you can see the original part, and on the right, my imitation. Of course, it was a matter of time before the other one split, but this one got a metal ferrule cut out of a piece of broken car antenna.
On the bottom of each truck is a snap on cover that covers the gears and keeps the bottom of the truck from spreading open:
One of those broke as you see here:
You can't really glue delrin, and the part's hard to replace, so once again, the engine was sidelined intil it occurred to me that there was probably another way to hold the truck together and the snap on the other side would hold the cover on.
There's a pair of posts that touch end to end and space the halves of the truck correctly. Here you can see them spread apart:
I brainstormed a number of ways to hold those posts together and settled on this wire staple through holes drilled in the two posts. The cover snaps on over the whole works and the remaining snap on one side holds it in place.
The original wheels were sintered steel, but they got dirty pretty quickly, so they're replaced with Northwest Shortline Nickel Silver wheels. Long ago, Athearn trucks had the bearings in the sideframes, and these wheels are the ones for that design, so apparently it's worth NWSL's while to make the upgraded wheels.
One other thing I noticed: Power is conducted from the trucks up into the frame by springy bronze tabs that touch screw heads on the frame. It's best that there's the same spring pressure on both sides so the truck is not biased to tip one way or the other. This can be adjusted by bending the tabs.
Until something else breaks, I've got a working locomotive and with the new motor magnets, it matches the other boxcab's speed well enough to double-head the two.
Carpe Manana!
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Posted - November 12 2022 : 1:28:29 PM
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neato I need to find one again 
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Posted - November 12 2022 : 1:47:04 PM
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quote:neato I need to find one again
Originally posted by microbusss - November 12 2022 : 1:28:29 PM
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Good hunting!
Carpe Manana!
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Posted - November 12 2022 : 6:15:05 PM
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quote: quote:neato I need to find one again
Originally posted by microbusss - November 12 2022 : 1:28:29 PM
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Good hunting!
Originally posted by scsshaggy - November 12 2022 : 1:47:04 PM
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in 14 days I will 
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