Rotary speed issue when cutting

K40, Smoothie on C3D mini running LB 09.02

Not used my rotary for cutting for a while now but I’m having an issue when cutting squares out.

The speed is OK when X is going +ve but when its -ve it slower causing increase in burning.

Checked the G-code and every time the X speed is always slower for some reason.

Tested on circles and other shapes and its all good.

This only happens on squares.

Any ideas guys.?%20v3

File attached of basic square G-Code in picture format, forum won let me upload Gcode file…


Did many many more runs and when “fill” is selected it works perfectly.

Select it to cut and it cuts 3 sides at the correct speed but when doing the return cut on the square it slows down.

I have tested this on flat using X/Y and it works perfectly every time.

picture of the G.code with cut using x/y

.So I still cant it to do what it used to do…

If I can find an earlier version will drop back to that see if it does has the same issue.

Any help or suggestions would be appreciated.


Ok. Managed to finally get some more time on this.

Whenever I use Rotary on fill it works right.when I try to use it on cut it still changes speeds on each cut @LightBurn any ideas ?

I have tried laserweb and it works accurately each time.

So I k ow it’s not the rotary device I have.

Tried to drop back to an earlier version but it won’t let me install.

I believe I have this fixed. Will need to do a little more testing, but there was a reasonably obvious bug in the calculation for feed rate when using current position or user origin modes.

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