Making my own milling power feed?

[choochoo_balooParticipant @choochoo_baloo]

I have just purchased a nice bench top horizontal mill.

Having read different pieces I gather that for a lot of milling, a powered cross feed is desirable for finish/consistency etc.

Before it arrives, I'm obviously unable to look around for mounting points. However I wanted to ask whether in theory the following would work:

12V car wiper motor connected directly to the non-handled end of the table lead screw, wired to a suitably 'beefed up' 12V DC model train controller.

Having tested a wiper motor from a 12V battery, I know that the feed rates would need to be considerably lower than the 12V speed of the wiper motor. Hence I cannot see why a train controller modified to take say up to say 3-4 Amps, with the knob turned down from 'full speed' wouldn't work?

Any advice gratefully received.

[choochoo_balooParticipant @choochoo_baloo]

[JasonBModerator @jasonb]

Did you see this thread last week?

[choochoo_balooParticipant @choochoo_baloo]

Just read it. Perfect thanks.

[Ian S CParticipant @iansc]

I think you may need a bit more than the train controller, my power supply is from an old Xerox printer, the transformer in it is about a 7" cube, as originally wound, it was an autotransformer, I wound another layer on top with 16 swg wire to give me 18 volts isolated, it's got a bridge diode rated at 35W. I geared the out put of the worm wheel down 2:1, the base speed is about 120 rpm. These motors will easily take 18 volts, and probably up to 24 volt.

Ian S C

[AjohnwParticipant @ajohnw51620]

I had a quick look around on stepper rotation speed. I only found info on moderately powerful nema 23's of the usual length but on this higher end brand it looked like they could provide full torque up to maybe 300 rpm. The 3" long ones can produce a lot more torque given ebay figures.

Personally I would want to use gears to couple to the lead screw because I wouldn't want the drive to sit proud of the top of the table so even more torque could be available via suitable gearing down. Maybe say 200 rpm to 60. Hard to be sure without trying it.

John

–

Edited By Ajohnw on 09/08/2016 11:30:04

[HopperParticipant @hopper]

Another alternative is to use an old cordless drill. You can set the output gearbox on the low speed setting and use the trigger mechanism with an eccentric for speed control. All you need then is a fixed output 12 volt supply good for a few amps.

[Author]

Posts