I am working on cutting my first part that I designed start to finish. For the sake of conversation, I am trying to cut a .375" wide by .500" deep by 6.045" OD circular slot in a piece of 1.25" acrylic plastic using a .375" HSS 2-flute general purpose end mill.

The part was modeled in Alibre design, exported through the "add-in" to SprutCam, and the code was generated using the Tormach PCNC-1100 postprocessor.

Mostly the first attempt went ok with two exceptions. Instead of a smooth circle the slot is broken up into straight line segments, Picture a "Stop" sign but instead of eight sides it has 40. Secondly instead of cutting the slot in one fluid spiral motion the mill plunges .25" cuts a slot in the CCW direction, reverses CW back to the starting point plunges another .25" cuts a slot in the CCW direction reverses CW back to the starting point, retracts, and shuts down. Why is it essentially cutting the slot in both directions instead of, plunge .25" cut slot CCW, plunge .25" cut slot CCW, retract done?

This was done as a "roughing>pocketing" operation through SprutCAM.

Attached is a *.zip that contains the .igs, .stc, and .tap files.

I just replied to your thread on the SprutCAM forum with what may be a more successful resolution to the faceting issue. If that site is down (all too common), here is a link to the STC file I created for your part:

http://member.newsguy.com/~mphenry/TopPlateGroove-MPH.stc

To create the file, I imported your IGS file into Alibre and then exported that as a renamed IGES file and then manually imported the re-named file into SprutCAM.

Mike

Is it actual Sprut or Dolphin

I am not really sure who that is directed to but my parts were created using SprutCam.