Smooth Engraving Issues

I’ve had my xcarve setup for a bit and decided to do some things with the compression bit ( and the engraved areas aren’t coming out smooth. Is this just the nature of the bit or do I have something else going on? I do not see this issue when I use the straight flute bit ( The only reason I’m trying this one is I’ve noticed the straight end mill breaking pieces off if it’s going around a sharp acute corner.

1 Like

I’ve had the same problem with the flute bit…not sure why either

Looks like the Z is slipping / flexing.

Compression bits only work as intended at full depth, thru-cut (using the length of the cutter), otherwise they behave like down-cut when doing incremental Z

Compression/Down-cut will want to push material down and if Z isnt rigid enoug it will lift every so slightly causing such marks.
Another possible reason, or adding to the above - is an untrammed Z.

1 Like


1 Like

Tramming = making sure Z plunge/retract truly perpendicular relative to the X/Y plane and isnt raked/angled after the waste board have been skim cut.

A tram gauge or something one can rotate to check equal distance from waste board.

The compression bit is designed to carve through material with clean accurate cuts in both top and bottom. The bit is designed to pull work into the center of the stock reducing or preventing tear out. That being said it’s possible that the forces it creates carving at full depth per pass are too great for the X-Carve. It doesn’t work if you aren’t using the full length of the bit. Check out this diagram to see how it works.


Thanks everyone. This makes sense. I don’t think it’s my Z axis because when I use a straight flute bit, I don’t have this issue. I’ve seen it in random places with the straight flute, but I get a pretty flush engrave per pass overall. I need to pick me up one of those tram gauges though. I used a simple square on my Z axis and it did a pretty good job but those gauges would definitely make sure everything is spot on. Can anyone recommend (and provide a link to purchase) a good gauge?

In a pinch “anything” will be better than nothing:

A compression and downcut bit are not the same thing and behave differently than you’re describing.

I am aware of that, which is why I specified a compression bit need to be at full depth to work as intended.
When doing incremental depth a compression bit will act as a “upcut” since only the bottom portion of it is cutting.