Lathe power lever fix

PeterT

Ultra Member
Premium Member
This might be lame, but maybe worth a post if it happens on your import machine because its somewhat irritating.

My 14x40 power lever is the typical 3-position lever. Down=forward rotation, Middle = off, Up = reverse. The lever rotates a hex rod rod which opens & closes contact switches inside a cover near the head stock. The positions are indexed by a bearing ball & spring which detente in some matching depression holes in the casting. Down & Middle always operated smooth, but Up would sometimes drop out & turn the power off while machining. Might have something to do with the ridiculously heavy duty Neanderthal casting & handle assembly that would look more at home on a car jack. The set screw is uber fussy, if you turn it too much inward, the lever can stick in too well into position & you can actually overshoot neutral throw the motor into opposite direction. Not good.

I dressed the holes with a ball end mill, they were crudely drilled. I lapped the neutral action so it slides in better coming from Fwd or Rev, that was another sticking point. The switches are triggered by eccentric cams, I confirmed they were set right & also tight. It finally dawned on me that the set screw was unscrewing itself over time so changing the setup. Tonight I got positioned it with blue Loktite to stay temporarily put. Then I had just enough threads to put another set screw behind to prevent the spring retention one from migrating. It feels a bit better, lets hope it stays that way.
 

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John Conroy

member
Premium Member
Yeah,,its a clumsy set up for sure. I always wondered why they need a 10 mm hex rod to operate a tiny switch. On my lathe the handle sticks out so far that I sometimes bump it with my hip by accident.
 
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