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Cutting air


New member
I've got a pocket that I want to rough with one cutter and finish with another cutter. The way I program it now the second cutter goes through the entire toolpath as if it was the only thing milling that volume. This is very time consuming and unnecessary. Is there a way that proe can 'know' what its already cut and not cut that again?



New member
Dear EvilSpeeder,

There are a couple of changes you can make to that you are not cutting air. The first is to trick Pro by setting the parameter STEP_DEPTH to something equal to or grater than the final depth of the pocket with no PROFILE_STOCK_ALLOWANCE set. Else you can use a sequence called rest milling. Unfortunately I have not used that before so you may need to play with it a little. Good Luck!



New member

Another thing you can do is the following. In the Volume sequence you can change your type to pocket milling. This will cut all the vertical walls first and then the bottom(s) of the volume.

This works well when the pocket is deeper then the lenght of cut on your e-mill.



New member
I think you could also use Local Mill, optimize it for no retracts. I don't know if Local Mill is still being used or not but if you use a smaller end mill the end mill will machine away the areas left from the larger cutter, but i think ctarmijo suggestion might be better.

If material is only be left on the sides i would just make a profile pass and pick the side surfaces of the pocket volume.


New member

I'm not much of a volume-type programmer (we don't do molds) but I know they have put in many enhancements for re-roughing and finishing. I think local mill requires a remainder surface (could be wrong) which is created from a surface mill sequence in the parameters REMAINDER_SURFACE YES.

Then, when you create the local mill you reference the previous sequence.

Also, though I don't want to point out the obvious, you could create a material removal feature after the rough sequence and then put in the next sequence and it will 'know' there is nothing to remove there - if you are using a volume sequence and turn on the trim_to_workpiece parameter. You may want to sketch the cut instead of doing an automatic as the automatic mat removal doesn't consider cutter radius.



New member
Local Mill does not exactly require the REMAINDER_SURFACE usage, although the remainder surface dovetails nicely with Local Mill by Previous Tool. Remainder Surfaces take a good long time to compute, though, and don't always give you a lot of control over what is selected.

Local by Previous Tool requires surface references, and two tools--it pretends to machine the surface with the big tool, and then figures out what the big tool would've missed, and gets it with the little tool.

Local by Previous Sequence is more useful, 'cause it takes a sequence that's already been made, figures out what it missed, and hits that with the smaller tool. Either way, it tends to be very much aware of what has already been removed.

Hope this helps.