[rwskinner]

I'm machining the T-Nut blank that came with my Phase II BXA QCTP. I have to take off a lot of material and I was curious how much I can possibly rough cut per pass. Here is my setup....

G0619 Super X3 with Spindle @ 500 RPM, with automatic feed
New 3/4" TIN Coated 2 Flute End Mill
Machining Steel, Manually brushing cutting oil on cutter and work peice.

Must take 0.560" off each eadge to trim width
Must take 0.260" for Thickness

I've done 0.050", 0.075, and 0.100" per pass.

0.100" per pass is not bogging the machine at all but sorta afraid to take much more than that.

I know there is probably no exact answer but I was curious how much metal this thing could possible hog.

[Donkey Hotey]

You're right: too many variables. Any more than 0.100 and you have to ask yourself how securely is the part held? Remember that for every cutting action, you're also applying that same force to rip the part out of the machine. I'd say that if you were hogging a large block, rigidly bolted to the table, that 3/4" endmill should be able to reasonably cut 0.5D (0.375") deep and full engagement (0.75"). That's gonna' generate a lot of heat, but if done right, it's the fastest way to remove the material.

The next question would be: is that machine rigid enough to handle that kind of cut? Probably not. It'll probably chatter like crazy and destroy the part and itself.

Would I even try a T-nut that way, on an open machine with an oil brush? Not on a bet. At 0.1" per pass, you'd spend far less time machining that one than making it over if it gets spit out of the machine, ruins the part and breaks the cutter.

Always, always, think about how rigid your work holding is before you attempt something like this.

[rwskinner]

I finished machining the new tool post Nut. Turned out great. I just took 0.100" off at a time until it was done. I kinda felt like that was taking off enough.

Man, that Phase II 200 Series (BXA) is darn near as big as the little lathe.... 10x22 G0602. Should gone with the 100 series.

Thanks,
Richard