Smooth bottom of tray issue

[WoodStudioIA]

I am cutting the Catch All Tray that was one of the monthly projects and I am getting an “X” in the bottom of the tray. It looks like the bit is dragging across the bottom. The picture is after I tried to sand it while still on the table. Any ideas what causes this or how to remove? Thanks.

[Rcnewcomb]

Does the X appear in the preview? If not then it may be an issue with material holding, the bit slipping, or the Z losing steps.

[adze_cnc]

Ask yourself:

• Is the machine at a complete stand-still at those points?
• How do Girl Guides create a fire with a rotating vertical stick?
• Does a router bit at a complete stand-still resemble a vertical stick?

[WoodStudioIA]

Does the X appear in the preview? If not then it may be an issue with material holding, the bit slipping, or the Z losing steps.

It does not show these marks in the preview.
I am running the Pocket Toolpath with an Offset Strategy with a Climb Cut. So the "X Pattern is along this path when you view the video preview.
I have .25" End Mill pass depth at 0.125".
Do you think if I switch to a Raster tool path it may help? Conventional vs. climb cut?

[WoodStudioIA]

Ask yourself:

• Is the machine at a complete stand-still at those points?
• How do Girl Guides create a fire with a rotating vertical stick?
• Does a router bit at a complete stand-still resemble a vertical stick?

So your saying the machine may be hesitating at those spots and rotating a "burn". I did not ramp the plunge moves. Should I change to ramping? Could this be the spots where it is plunging in a "Offset Strategy"?

[Charlie_l]

Raster and maybe slow the rpm.

[TReischl]

That strategy (the one you used) is the absolute worst IMHO. It is virtually guaranteed to produce results like that. Precisely because of what Adze wrote above. Not only that it guarantees that the bit will be cutting across the grain and with the grain. That will also cause light to reflect off the cut fibers differently. And we can see that.

On my machine those lines are very narrow when I get stupid and use that technique. The reflected light issue is very noticeable. (I wasn't saying YOU are stupid for using it, you are just getting started, now me, I should know better, but every now and then. . . .).