working with drag knife causes rough movement

[cnc-peter]

Until now I have had no problems with rough movements on my CNC milling machine (start-stop-start-stop,.... with acceleration).
Since I use the drag knife, the machine moves very rough.

I think the problem is that the cutting direction changes constantly. See the attached screenshot
File mill_direction: all the arrows are in the same direction
File: drag_direction: the direction changes very often. The machine starts, stop, starts, ........

BTW: the same file was loaded and then the toolpath for the drag knife was generated in ASPIRE.
The result is absolut OK. No problems where detected.


How can I avoid this rough movements ?
I am thankful for every hint
Regards
HP

[Les Newell]

The arcs probably aren't exactly tangent to each other so SheetCam needs to do a small realignment move to ensure accuracy. You can tell SheetCam to ignore these small moves. It reduces accuracy so you have to make a tradeoff between accuracy and smooth cutting. Edit your drag knife operation and move the accuracy slider to the left a bit and try again. You'll have to experiment a bit to find the best tradeoff between accuracy and smoothness for your application.

[cnc-peter]

I have changed the accuracy in two steps:
first: lowest accuracy: the movement is a very little better
second: max accuracy: the movement is very very very rough
So I think there must be another way to fix this problem