.125 hole 3" deep

[MIL-TFP-41]

ok, I have done this many times in the past, deep, smaller holes. Typically I use a pilot drill & go about 2x dia deep. Then comes the long one, enter with a slow RPM, ramp up the RPM and coolant (will dwells in the appropriate places) & go to town, no pecks. Nothing to it. On the machines I have done it on, we had 1000PSI coolant. Now I gotta repeat this process on a machine (A Multus) that has only 150-200 PSI thru coolant. I am thinking I might have to peck....but thought I would ask & see what others thought.

[Tim Johnson]

The 1/8" dia is pretty close to the Mendoza line as far as the flow rate vs. pressure. Chip-break and cut the feed by a third if the material will allow it..

[Matthew Hajicek - Singularity]

Job it out? (duck)

[MIL-TFP-41]

whoops...forgot to mention that its just 6061 alum. Farm it out....not gonna happen, lol.

 

Chip break cycle is a good idea.

[Bwank1124]

I haved drilled 1/8" holes 5-6" deep in 6061 a lot at a previous place. I usually pecked at half the diameter of the tool and have had great success. That was using a Guhring series #503 I believe.