Thread: another qctp variation

Saw a youtube video a few days ago with a variation on controlling tool height.

Was unable to find the video again but have made a sketch for your perusal.

Thought it was interesting but maybe also a bit awkward and clumsy compared to most other qctp variations I've seen.

The chap was using this for ordinary cutting tools as well as boring bars.

Bill

Hi Bill, Guys,

I had that Idea years ago I used a 3/4" inch piece of round bar, held in a "T" piece that fitted in place of the tool. Drilled it out 3/4" whilst fitted in the lathe tool holder, so it was bang on centre hight. Slit it with a hacksaw and used a single M8 Cap screw to lock it and stop the bar from moving. The 3/4" bar was put back in the holder, nipped up and the end drilled to take 8 mm HSS tool bits but 1/4" inch off centre, using a 2Ba grub screw to nip the toolbit so when rotated its cutting edge could be moved up and down. I cross drilled the back end of the 3/4" bar to take a tommy bar to rotate it.

After a while it got consigned to the scrap box. It was more trouble than it was worth rotating two items to get the cutting edge at the right hight, and it added about an inch to the overhang of the tool holder ! It seemed like a good idea at the time !