On May 24, 8:02*am, "Joe AutoDrill" wrote:
I guess you don't have the torque and linear force to run an indexable
drill? They have excellent chip breaking capability.

Depends on the hole size. *I can go to 3 HP with very low RPM and create up
to around 1500 lbs. of thrust. *However, the machine is only about 120 lbs.
total so it's not going to be nearly as steady as a Bridgeport or even very
large drill press, etc. *It's tough to make a hole with standard tooling
(step works) at that size as the micro-vibrations simply kill some tooling.

The problem isn't so much the stability of my drill, but the fact that
nobody wants to build a 5,000 lb. fixture to hook up a 100 lb. drill.

Running a ~Ø1.0 indexable drill (two inserts which work out to one
flute) in 6061 aluminum on our cnc lathe, spindle reaches about 40% of
10hp. That's 0.785sq" of area at 42ksi tensile. 2" works out to
3.14sq" at 60ksi (1018 mild steel). That's quite a bit more...


You can get indexable trepanning tools but they usually start at Ø3"+
and they look pricey.

I'm selling the machine, not the tooling so... *

Yup. Couldn't hurt to contact the company about your app.


Thanks as always for the thoughts Robin. *You and a few others around here
make the group worthwhile above and beyond the entertainment value of the
spam. *
--

Glad I could be of some use

Regards,

Robin