Kerfs going wrong

Hi guys, having major dramas today and have wasted so much material in the process. Long story short, I had glass mirrors made to suit a product I sell. Worked out all my kerfs for the different shapes, mirrors are inset into acrylic.

Today one of my particular shapes, everytime I try to cut it, either the sizing or kerf is going wrong… my shape is 140x140mm and the kerf needs to be -0.35 to fit my mirror inside. Too much material is being cut instead.

I have tried the following:
:black_small_square:︎ Using my original design made in lightburn
:black_small_square:︎using the dxf file the manufacturer used to cut my glass
:black_small_square:︎using an old lightburn file and fixing up the sizing and kerfs to match what it needs to be.

It will finally work on one go, so I save the file and then start again and then the cycle happens all over again.

Surprisingly turning off the machine and restarting lightburn seems to help but i cant do this with every cut.

I’m a bit puzzled, kerf is normally assigned to both parts by LightBurn, you only have one part, so kerf should be less than what you set. (actually half)

My outer cut is set to 0, inner cut set to -.35, the glass i had made to sit inside of it is 140x140mm.

Upon further testing tonight the error seems to happen when i do both the inner & outer cut in the same job… if I run 2 jobs instead I dont have that issue. Usually i can do both cuts without any problems