On Mon, 27 Sep 2010 07:19:21 -0500, Karl Townsend wrote:

How bad were the chips?

I had no trouble with my mystery metal AL. Some AL is a stone bitch to
feed the chips up the drill bit, others work great. As nearly all my metal
falls in the mystery metal class, i can't tell you which grade is best.

You should feed maybe twice as fast as my small run.

Once, after hours, I found some really spiffy pieces of aluminum out in
back next to the bandsaw. I wanted to make a trinket, and the resident
machinist taught me how to use a mill - I was astonished how much metal
he could hog off that aluminum block; Previously, as a hobbyist, I had
used about a quarter the feed rate this guy was getting away with.

I once got tasked to drill a couple of 1/2" holes in a 3/16" plate of
304SS. I din't even know you _could_ drill 304SS with an ordinary
twist drill, but again, my coach(es) said, "GO FOR IT!" I really bore
down on that handle thingie that extends the quill, and the stainless
just gave way. I heard that sound that you hear when one mongo chip
is being produced, and it felt almost like the drill was pulling itself
into the work - I was through 3/16 of metal in a matter of seconds,
almost effortlessly!

So, I guess I'd have to admit, when I'm playing with metal, I should be
more aggressive with my cuts. :-)

I once saw a guy deburr a steel part with an ordinary pocket knife. Does
that dull the knife?

How can steel cut steel? Howcome the part doesn't cut the bit?

Thanks,
Rich