Mill Marks

Wondering if anyone might be able to help me troubleshoot. I’m getting milling marks on pretty much everything I do. How much of this is expected, and how much of it is the machine out of alignment / calibration.

I’m using VCarve to mill .06" deep at a 45 degree angle. It mills flat when moving to the up and right. However, when moving down and left it leaves behind the little marks that you see.

I’ve been sanding them off, and it seems to work pretty well, but if I could avoid the marks, that would be ideal.

looks like either the gantry is shifting with torque or the step over is a bit high - do you have a strengthening mod on the cross extrusion?

I don’t have the stiffening mod, I was going to work my way towards that. The 30 minute one I saw used M5 bolts, but they are too big to fit in the gap. When I force one in there, the box that rides the rails won’t ride past it. I guess I could try and find some M4 bolts and see if that works.

Yeah, it looks like the bit is not perpendicular with the surface. Without some kind of stiffing mod the gantry will twist just a little under load, causing the bit to angle.

I highly recommend doing the 30 min mod (getting some smaller bolts) and see haw that affects things.

Use M4 bolts not M5 :slight_smile:

I suspect that when it is cutting in one direction it is traveling against the rotation of the bit (conventional) and all is well. But when going the other way it is “climb cutting” or traveling with the bit rotation and with what appears to be a significant step over being used the bit is grabbing the naterial and pulling the router out of perpindicular alignment with the surface.

Try a smaller stepover. if that reduces it, a stiifening mod will probably pretty much eliminate it.

Also double check the set on the x axis/carrige v wheels.