Had a job requiring some large(for me) chunks of aluminum. Stock was 9" diameter x ~3.1" thick, 19 lbs. I wanted to come up with a process that wouldn't take forever on such a small mill. I also needed a tool that could stick out > 3.5" from the spindle face without chattering like crazy. Thought I'd share this. I got a 3/4" clamp collar from mcmaster carr to clam directly on a 3/4" shank tool (iv'e done this before, but not on a tool this long). I wanted to use a 3/4" tool to increase rigidity sticking that far out. The tool is a .787" diameter,3/4" shank ABtools shear hog single flute cutter with a 6" long shank cut down to 5". I found the happy place for cutting parameters was around 2.95 cu"/.min. .1" DOC .59" WOC 50"/min. You can certainly push this tool harder, but at that length of stick out this seems to be the sweet spot where I can walk away(this tool is really loud) and let her rip. I bored the I.D. for a sleeve bearing. The interior mating part, I left .003" stock from roughing with the shear hog and used an extended reach 1/2" end mill to finish the walls. Came out great, now I gotta make 3 more.