Variable Feed Speed Control for Mini-Lathe

A good while back I bought a Grizzly mini lathe, and like my old Atlas 6 incher, I had to switch the gears to adjust the feed rate. My solution for that is pictured below.

I center drilled the lead screw with a 5/16" drill, then drilled and tapped a setscrew hole an inch or so from its end. I then made a female to male adaptor that slid into the end of the lead screw and fit on the shaft of a Grainger gearmotor. The male end of the adaptor had a flat milled into it. A drilled detent would have accomplished the same thing. I drilled and tapped a couple of holes in the end of the lathe and made a motor mounting bracket that bolted in place.

A DC model railroad transformer controlled the feed rate in forward and reverse.

Attachment 38077 Attachment 38078 Attachment 38079 Attachment 38080

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Thanks tmate3! We've added your Mini Lathe Variable Speed Feed Control to our Lathe Accessories category,
as well as to your builder page: tmate3's Homemade Tools. Your receipt:

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So, if you add a way to read RPM you "could" do rudimentary threading?

Pretty cool idea. I have that same exact DC speed controller.

Quote:

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Originally Posted by cementtruck

So, if you add a way to read RPM you "could" do rudimentary threading?

Pretty cool idea. I have that same exact DC speed controller.

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I believe you would need a way to sync the spindle speed with the carriage movement.

I guess a stepper motor moving the carriage and a hall effect sensor on the chuck end would be the only way to get that 99.98% to synch up. Back to the drawing board ... and the ELS forum (*sigh).

Still a great project though if all you need is a quick way to get that carriage back and forth quickly.