I'm still wrestling with some issues with Fusion360 tool paths and UCCNC. I've enabled smoothing set to .005" or higher and played with CV settings in UCCNC with some success, however one common thread seems to be that UCCNC doesn't want to keep accelerating through multiple lines of G code despite the path looking smooth and straight enough for it to do so. This is all related to 3D surfacing BTW, I haven't had the same problems with 2D yet. I think there may be issues both with post processing and UCCNC, and could really use some help to understand this more. Despite high smoothing values, I don't usually get arc segments in my tool paths, typically its just lots of straight segments. In fusion I've been inspecting the tool paths and number of points in them, and even when they look good there, it's no guarantee it will run smooth on the machine. One strange case I tested was running a spiral morph finish pass and a scallop finish pass made from the same geometry. The spiral morph had more simultaneous 3 axis movement, yet ran fairly smooth @ 6500mm/min. The scallop that had less 3 axis movement, yet it couldn't accelerate past 3000mm/min despite the same feed rate as the spiral morph. Neither one had much stuttering, but the more complex path could accelerate to the set feed rate while the simpler one couldn't. The only culprit I can think of is that the spiral morph path had arcs in it while the scallop didn't. Considering the shape, the scallop path could have easily fit lots of nice arc segments but it didn't. Any ideas why a post processor would ignore arcs?