My boss had a wild idea, which of course was placed on me to figure out. We have lengths of boxed 6061 T6 aluminum which is about 1/2 x 2 x 10' in length. The idea was to do a simple program to cut the ends to size and drill a few holes in the piece, so we did not have to outsorce this work. I reminded him that this is a woodworking machine, with no coolant, or adequate workholding for metals, but he insists on figuring out a solution.
I first tried a 1/2 solid carbide down spiral that we had a crapload of. I ran the tool at 15000 rpm which is our normal spindle speed, and feed at about 100 ipm. This did cut the piece, but it was real jagged on the ends (I believe it was moving the piece on the table) and played hell on the bit. We then ordered a 1/2 TiCN coated triple flute upspiral, which was recommended to us from our tooling supplier. We ran that at the same speed and feed, which just mangled the end and drug the head into the peice. We tried again with a fresh bit, this time as slow as the machine would go (3 ipm) this time it just melted the metal and made no chip formation.
We have the piece held down with the pins using the supplied clamps which holds pretty rigid, so most of the problem has to be with our tooling choices or our feed speeds. I was thinking of using a multi flute roughing bit but I dont know if that would make things any better. Any help would be appreciated..