Thread: Two fold post, Wasino LJ63M m12 ?? and hex milling on it.

That makes a little more sense. So, I recommend that you do what I suggested in my last post and program the points as if the hex is larger by the diameter of your cutter. And make sure your cutter is touched off to be on center with the spindle. That should give you the geometry you are looking for.

The way the hex is aligned with the C and X is fine. That's the same way I would do it.

If you'd rather climb cut instead of conventional mill, just change the sign of your positions so that the tool goes around the hex in the opposite direction.

For conventional milling a 1.602" hex with a 3/4" end mill, your program would look like this...

X1.3579C1.176
X-1.3579C1.176
X-2.7159C0
X-1.3579C-1.176
X1.3579C-1.176
X2.7159C0
X1.3579C1.176

For climb milling...

X1.3579C-1.176
X-1.3579C-1.176
X-2.7159C0
X-1.3579C1.176
X1.3579C1.176
X2.7159C0
X1.3579C-1.176

Originally Posted by wmpy

That makes a little more sense. So, I recommend that you do what I suggested in my last post and program the points as if the hex is larger by the diameter of your cutter. And make sure your cutter is touched off to be on center with the spindle. That should give you the geometry you are looking for.

The way the hex is aligned with the C and X is fine. That's the same way I would do it.

If you'd rather climb cut instead of conventional mill, just change the sign of your positions so that the tool goes around the hex in the opposite direction.

For conventional milling a 1.602" hex with a 3/4" end mill, your program would look like this...

X1.3579C1.176
X-1.3579C1.176
X-2.7159C0
X-1.3579C-1.176
X1.3579C-1.176
X2.7159C0
X1.3579C1.176

For climb milling...

X1.3579C-1.176
X-1.3579C-1.176
X-2.7159C0
X-1.3579C1.176
X1.3579C1.176
X2.7159C0
X1.3579C-1.176

Since I've set the machine up for another job and can't test what you're saying right now, how can programming bigger numbers do anything but make a bigger hex? In case you missed it the current problem is it making convex flats with the corners undersized.

Read post #19 again. The convex flats are because the program was written without compensating for the radius of the tool.

"My guess is that you're looking for a 1.602" hex, didn't compensate for the end mill in the program, and got the machine to kind of cut to size by moving the X offset up so that the center of the tool is no longer zeroed at the center of the spindle. That would give some funky geometry like you're getting."

Yes, 1.602" flat to flat.
No I didn't change anything in X offset, the only change to made it cut to size was to touch off the side of the EM on a cut dia and set GEO. Up to that point I was only trying to get a hex and didn't care what size. At that point I did touch the edge of the EM at the edge of the a turned, known dia. so in my thinking the edge should be on diameter instead of having to comp to it.
I wasn't arguing above that it can't happen, I'm asking how does it work to program bigger numbers to get rid of the convex, or is that black box magic and nobody knows?

It is kind of black box magic. I have a faint idea of why it needs to be programmed like that, but not enough of an idea to be able to explain it.

I think of it like I'm programming a mill. I can't expect to program a hex to the exact dimensions and get the desired result without compensating for the cutter. The same with polar interpolation on a lathe.