I’ve had almost the same exact problem from an unusual, but easily fixable source. I was leaning on the X-carve to watch it work. The frame was flexing and moving the piece down just enough to make those kind of marks. The solution? I don’t lean on it while it works anymore.
There are two possibilities here:
You are taking off too much material during pocketing and the z axis is deflecting/lifting while cutting. When it goes back to clean up around your letters the machine is dropping to full depth and taking off the material left behind as a result of the machines deflection.
Your material is warping or lifting during the cut. This is very common with mechanical hold down.
OK… so this morning. I did two carves both the same file, same material (cedar), placed in the same location on the unit, all lockdown points identical. I’ve addressed all the suggestions previous in this post… The pictures show the two different carves as they came at of the x-carve. My problem seems to be with these smaller pieces, they are 16x5 1/2 (and others I’ve done which are smaller yet). as you can see with the larger carve in pine 24x12, in every single layer the bed came out perfect. Any insight on what is going on? I’m at a loss here…
That is really strange, is this only happening with that Sauna file? Maybe try a file that you know cuts clean in lets say pine and then try it in cedar. Maybe there is something funny with you file.