Author Topic: Contactor Rings on Jacobs worn out  (Read 352 times)

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adobejoe

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Contactor Rings on Jacobs worn out
« on: September 04, 2017, 07:22:12 PM »
This is on an older Jacobs and I suspect the reason I am not getting near the electrical output. Ideas on how to rehab/replace copper contact rings? See pics.

Adobe Joe

adobejoe

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Re: Contactor Rings on Jacobs worn out
« Reply #1 on: September 04, 2017, 07:24:02 PM »
here are rings

joestue

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Re: Contactor Rings on Jacobs worn out
« Reply #2 on: September 04, 2017, 11:24:40 PM »
copper water pipe, epoxy. it helps to have a lathe but you don't really need one to get them mostly accurate.

i made slip rings for a 3600 rpm generator from 3/4" copper pipe and electrical tape.. concentricity on the order of .02" didn't even matter at that rpm, definitely won't matter for a wind turbine..

copper on copper is probably not what you want. alternatives would be relay contacts from a 35 amp or larger relay. they are often silver and a few alloying elements to harden them. the silver should be thick enough to get a pencil eraser sized contact area after the curve is broken in, of course, you want several of them for each.


if you are careful you could solder the new copper rings right over the top of the brass old ones, if the diameter is close enough that you could find a suitable spacer to fill the gap.


you can probably clean those rings up with a file, then progressively sand them holding the sand paper against a flat, curved surface. diamond turning them in a lathe is overkill and not required for this application, but its the usual route for cleaning up motor commutators and sliprings.
« Last Edit: September 04, 2017, 11:34:29 PM by joestue »