Mini-lathe POWER FEED - DIY

[Crusty]

I used a Dodge Ram wiper motor for the power feed on my milling machine and a year later it's still doing what I need it to do. In the motor there are 3 brushes, a common, a low speed and a high speed brush which produce 2 speeds but I found that if you isolate the common from the case (which connects back to the battery negative) then you can apply power across the low and high speed brushes and get a third fastest speed. I used a 3 gang, 6 position rotary switch to control it and I have 3 table speeds in each direction. I included a power switch for off and limit switches at each end of the table's travel to automatically stop the drive at each end and with an adjustable spindle speed I can adjust it for a good cut at any particular table feed.

Here it is before I wired it up. There's a stub shaft on the end of my lead screw connected to a deep socket and a hex stub connected to the motor and the motor assembly slides in or out on pins to engage or disengage the feed. I included a brass shear pin in case of motor stalls but I suspect that the plastic gear inside the motor protects the shear pin so I always keep my thumb on the off switch.

Wiper motors deliver a surprising amount of torque and are handy and affordable for a variety of projects.