HSM Express+Tormach undersized holes

[billbo911]

Originally Posted by Cory

Maybe this is a function of how HSMExpress works, but I don't really understand why this is even a problem. Aren't you hand entering a depth to cut to? Or is it selecting that depth based on the depth of the chain you selected?

If it's the former, just put in -.1875 or -.250 for a .125" wall thickness tube.

HSMExpress selects the depth of cut based on the contour/profile you select. So, if the part being milled is modeled with a wall thickness of .125", but in reality has a wall thickness of .127", in a perfect world, the milling operation leaves .002" of aluminum at the bottom of the hole.

What I have found is that if I just set the "Bottom Height Offset" to a value of .010", then the end mill will extend .010" beyond the selected profile. This will cut the hole cleanly as long as the material being milled is less than .010" thicker than the expected .125".