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How to electroplate onto a cathode rotating at 1000 RPM

1998

We are plating onto a rotating cathode and having problems getting power through the motor to the cathode. If anyone has any suggestions. We are plating at 200 amps and the motor is spinning at 1000 rpm.

Thanks for any help
Jon Hughes

Jonathan Hughes

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The only help I can give you is to tell you not to give up

Yes, there are mercury switch contacts designed for exactly this purpose, and which can carry 200 Amps and more.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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Shouldn't you be insulating your motor from your components ? Don't want any stray currents, Try carbon brushes for a cheap & easy way to get the plating current to your part. Just look inside your washing machine at the motor for the principle. a local electric motor distributor should be able to advise you on the size/contact area to carry your current.

Regards

Richard Guise
- Lowestoft, U.K.
1998

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At that amperage and RPM, tinkertoy homemade units that I have used will not suffice. If you want to try, use a cast bronze bearing and apply the lead to the bearing housing. It needs to be fairly sporty in size if you want it to last.

Store bought units can be found in the Thomas Register.

James Watts
- Navarre, Florida
1998

I could not help but notice that you say you are plating at 200 Amps, what is the voltage? Also, are you actually running through the drive motor, or is the cathode isolated from the motor? If it is isolated, then an arrangement to introduce the plating current can be established like one would use for plating of wire or strip.

Richard Zuendt
- Garfield, New Jersey
1998

Hi, I came across an exchange about rotating cathodes connections purely by accident while searching another topic. The thread dates back a few years but some one may still care about solutions. I have experience with rotating connections operating at 7,000 A beneath the surface of a hard chrome bath. Working above the surface should be relatively easy.

John Carroll
- Gillette, WY
2003