Hey guys, Mastercam newb here. i am in the roughing op of a part i have programmed. i have backplotted and verified the program. i ended up crashing my part due to my cutter taking a very hard undercut during the Optirough and pulling the part out of the workhold. i put another part on because i thought maybe the part shifted and that is why it undercut, but that wasnt the case. i do not understand why it would undercut on a Optirough. Our main programmer told me tl use "stepup" in the toolpath control, i dont quite understand the "stepup" parameter and would appreciate if someone could explain what it does, why/how it would prevent an undecut. would also love to know WHY it is taking an undercut, it just doesnt make sense to me.