I have one that I have used about 50 times with great success. I drill a lot of steel and it's a real time saver to keep bits sharp. My 9/16 and 5/8 I still do by hand, but for everything 1/2 to 1/8 it works great. It is very useful on unique bits, like the ones inside wood screw countersinks that have a flat side (and thus can't be replaced by regular bits when they break). I've never had a problem with them wandering, but I center punch and go up in ~1/4" increments when I drill, hand or press, and I use cutting fluid on the heavy/hard stuff. The drill doc is well worth it.

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1982 Mercedes-Benz 300CD
1982 Mercedes-Benz 240D - stick