Maybe somebody smarter than me can figure out what is happening
here... I do a lot of drilling in aluminum. Anywhere between 1/16" and
1/4" thickness and between 1/4"-1/2" in size usually. I have no idea
why, but the only drill bit I have been able to cut very clean holes
with, is a basic HSS black oxide bit from Hitachi. There's nothing
special about them, but they work very well. I've tried what seems
like every other type and brand of bit known to man, and none will
work as good as the Hitachi... I've even tried centering bits and
other much more expensive ones. When I look at the Hitachi, I don't
see anything different about it as compared to numerous other bits.
It's got the same angle and everything as at least 10 others I've
tried, but they don't work. Usually I just get a sloppy hole with
ridge build up, messy sides, and less than perfect circle.

So why not just buy the Hitachi ones then? They just started offering
a new kind and you can't get the old ones. The new ones don't work
either.

It's a stupid problem, but I can't figure out what the deal is.

Thanks for any help,

Dave