Motorising a Mill-Drill Table

by John

No, I did not tidy up for the photograph.

I have had this round column mill-drill for quite a few years. The head and the table are both able to be raised and lowered with a rack and pinion operated with a handle. It is a heavy unit, and raising the head or table by hand has always been a struggle, so much so lately that I have been planning to motorise the movements.

There are a few YouTube videos on the subject, but none for my particular setup. And both the head, and the table with its XY table and milling vice, are very heavy. I decided to really gear down the mechanism so the motor could be compact and not overloaded. So that meant another worm and gear in the train. I ordered a 1:40 worm and gear, but meanwhile a friend offered me one from his junk box, which I happily accepted. (thanks Stuart.)

A powerful, reversible, compact motor at a reasonable price, and not requiring complex wiring, is not readily available. But, then I thought, how about trying a reversible electric drill, with speed control? I have a Metabo 750w drill, and I decided to try that. If it worked I could buy another one on Ebay for about $AUD250. As it turned out, it is so easy to attach and detach the drill, that I will probably not need to buy another one. (note added March 11. I bought a second hand Metabo drill on Ebay for $30! It is very second hand, and battered, but has forward and reverse, 2 speed gearbox, and variable speed regulated by trigger pressure. 600 watts. Works like a charm!)

The next decision was whether to attach the motor to the head or the table. My original plan was to attach it to the head, but on testing the power required to turn the handles manually, it was obvious that the table was easier to move, so I have positioned the head at its maximum height, and will probably never need to move it again. The new mechanism was installed on the table.

The following video summarises the assembly of the components, and a brief demo. Click on the arrow to view it (10 minutes duration), or go to YouTube to see it full screen. It was shot on my iphone held vertically.