Mill / Drill power feed.

This is a power feed that I made some years ago for my Mill/Drill.

The motor is a 240V DC unit with double reduction gearbox. Final
drive is 60rpm. Speed control is by a simple light dimmer switch
which with the standard 10 tpi lead screw gives a speed range from
a max of 6" per minute to nearly stationary.

The output shaft of the inline gearbox has been extended by using
a bronze bush pinned to the end of the gearbox. The other end then
fits onto the extended portion of the leadscrew where the handwheel
normally sits on the mill/drill.

A keyway has been machined in this bush to carry a long key and on
this bush slides a dog that engages with the handwheel dog. This is
activated by the alloy grip ring that you can see in the photo by
two selector pins that engage the dog.

The whole arangement is secured by two screws that locate the
extension tube to the register on the end of the mill table.
One screw can be see in the picture. In use the drive can be left
on the machine all the time and just brought into play as needed
by the sliding dog.

Not visible in the photo is a micro switch fastened to the front of
the table to contact the travel stops so that it can be left running.
The black coiled lead is visible leading to it.

Photo at:-

http://www.metalworking.com/dropbox/_1999_retired_files/milldrill.jpg