Z alignment off slightly between left and right side

I am cutting some additional holes for threaded inserts on my Shapeoko’s stock waste board. I’m using these to mount a supplemental waste board. The design has a very shallow outer ring/pocket for the top of the threaded insert and then a deeper hole for the body of the insert.

The hole on the left side of the waste board works as it should.

However, the same design on the right side “machined air” resulting in no outer ring/pocket.

I even tried re-zeroing the Z on righthand side of the board with no better results. I have noticed before that I sometimes get a very thin layer of material left when I try to cut out designs on one side of the board.

The rails, gantry, and waste board are level. I realize there are multiple things that I could adjust–lots of screws. Is there a best place to start?

If it makes any difference, I have a standard size Shapeoko with a Z-Plus and Carbide 3D router.

I would make sure your file is setup correctly and it is not trying to cut a different height there. Especially if you re-zeroed your Z axis near the problem area. If it does turn out to be a mechanical issue and you want to adjust your machine to get it closer, it is quite the job and it is much easier if you have a dial indicator and magnetic mount. I remove my router and attach the mount to the Z plate. From there you can find how you need to adjust your machine. It will probably be a combination of the X and Y end plates that will need adjustment. EDIT: I just loosen the screws and use a clamp to hold the rail in the new location while I tighten everything.

1 Like

If everything else is level, square, and plumb, then the next thing to try is tramming the spoilboard.

Best thing to do is add one to the MDF baseplate and then surface that.

Discussion on adding one at:

Files for this at:

1 Like

@nwallace, good point on checking to make sure the file is setup correctly. I checked and it is (would have preferred for you to be right!).

Before I try more involved solutions, I’m going to go through those final squaring/alignment steps in the manual one more time. I did check to see that things are level on the machine, but there’s still a little bit of wiggle room even when the level’s bubble is in the center–and that’s probably enough to throw things off here.

The last time I squared the machine, I did it by myself. I thought everything was okay, but I want to do it again with a second set of hands available to tighten the screws.

So, I re-sqaured the machine and also adjusted the tramming screw on the Z-plus. That seems to have fixed the left-to-right differences. There is a tiny bit of difference front to back, but surfacing the supplemental wasteboard appears to have addressed that.

1 Like

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.