"gtslabs" wrote in message
oups.com...
I am making an attachment to my knee mill height hand crank. I drilled
a hole in a rod to match the diameter of the crank shaft. However there
is a keyway that I need to mill out of my adaptor on the INSIDE
Diameter. I dont see a Woodruff cutter working in this 5/8" hole.
I can mill it but it will not have square corners. What is needed to
get the square slot?
Thanks
Steve

There are two "right" ways to do it. One is with a keyway broach (not real
cheap). They come in all the standard sizes. The other way is to cut it
with a shaper, if you know someone who has one.

But, for a "one shot" deal, you can use the mill as a shaper. Run an end
mill down through it to get it to the right width and depth. Then take a
boring bar or grind a piece of drill rod to make an appropriate cutter and
chuck it in the mill. Put the mill into back gear, if it has one. Rotate
the mill to position the cutter (easy if you can get at the belts...) and
then use the quill feed to drive the cutter down through the work, cutting
out the corners. Use the table feed to move the work for successive cuts.

You can do the same thing with the lathe, holding the work in the chuck and
driving the boring bar with the carriage feed.

Jerry