Left-Hand Tools and Tool Holders

Tools that rotate counterclockwise require tool holders that won't loosen from the effect of that rotation. February 20, 2011

We have a small job that requires the use of a left hand compression cutter. For anyone that uses these do you use a left hand tool holder as well, or just run them in a standard rotation one?

Forum Responses
(CNC Forum)
From contributor M:
I almost always use a LH tool holder, but typically, my left hand cuts are very short duration without a lot of load on the tool, so I probably don't need the LH tool holder. We use a torque wrench to tighten the collet nut properly so it would probably be ok, but I prefer to play it safe.

From contributor F:
The opportunity for the tool to loosen is when the spindle stops and starts with a standard RH collet nut. If you keep the spindle on there is much less chance of a problem.

From contributor B:
I would use a solid holder that uses a set screw on a flat to drive the tool this way you can cut either way. I would never use a RH Collet Holder in combo with a left hand tool.

From contributor Y:
I never knew there was such a thing as a left handed tool holder. I use a left handed down cut bit to score along edge banding prior to mitering plywood parts (works like a dream), and have never seen any issue with the bit loosening up in the chuck or collet. When I really get going on jobs requiring this process, that particular tool gets started/stopped about 20 to 40 times a day. Even still, now that I know there's a left handed tool holder, I think it might be worth investigating.