Just wanted people's opinion on this... I need to create a flat spot on 1/4" aluminum rounds for both 4-40 screw holes and 6-32 screw holes. The flat spot needs to accommodate the screw head size, but also the nut size, which is a little larger. I guess this would mean the counter-bore would have to cut down about 1/8". Most of the bits I've seen don't seem to counter-bore a wide enough spot. Is there a bit where I could get, say a #36 hole with a counter-bore a little wider than 1/4"? This would be used in a press, not a mill. Hundreds of these have to be done, so it be great if it could be done with one bit/tool.
Thanks,
Dave