15" Leblond lathe servo shift repair?

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Richard_W
Posts: 2031
Joined: Fri Jan 10, 2003 1:00 am
Location: Molalla, Oregon

15" Leblond lathe servo shift repair?

Post by Richard_W »

I am trying to fix a friends 15" LeBlond lathe. When its supposed to brake and shift it doesn't. I replaced a micro switch which was bad, but that didn't fix it. I have to open up the back of the lathe and manually push the contact in for it to shift gears. Any ideas of what to check?

Richard W.
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Will's 2882
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Joined: Thu Jan 03, 2013 9:31 pm
Location: Oakhurst,Ca.

Re: 15" Leblond lathe servo shift repair?

Post by Will's 2882 »

Most Leblond servo shift have a mercury switch on the motor shaft that will make (close) when the motor stops turning so unit knows it is safe to begin the shift operation. They lose some of the mercury over the years and don't make contact any longer. You can't buy that switch now and the replacement that they is very expensive, it's an electronic unit that they came up with to avoid using mercury.
Richard_W
Posts: 2031
Joined: Fri Jan 10, 2003 1:00 am
Location: Molalla, Oregon

Re: 15" Leblond lathe servo shift repair?

Post by Richard_W »

Will's 2882 wrote:Most Leblond servo shift have a mercury switch on the motor shaft that will make (close) when the motor stops turning so unit knows it is safe to begin the shift operation. They lose some of the mercury over the years and don't make contact any longer. You can't buy that switch now and the replacement that they is very expensive, it's an electronic unit that they came up with to avoid using mercury.
There is a light on a blue box that shows it working when the spindle stops. Spindle runs and the light is off and the light turns on when the spindle has stopped.

Richard W.
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