Z-Axis trouble when cutting with Easel

So I have a new X-carve, and I’m new to CNC, but I’m having a particularly hellish time with the Z-Axis, and I am now convinced that it’s not me. Its a 1000mm machine with an Acme screw and Nema 23 motors.

Basically the Z-Axis is cutting somewhat “interestingly” here are some examples (in inches):
A cut for a .204 acrylic needed to be set at .196 or it would cut through the waste board
A cut set at .22 for an inlay proceeded to cut through a .44 birch plywood board, so I hit the stop switch, I have no idea how deep it was going.
A test cut of .1 depth measures at .228 with the digital measure.

Since I plan on using this for veneer inlays, I need precision depth. I’ve troubleshot the hell out of this thing, the Y-Axis had current issues so I adjusted that potentiometer, so I know that behavior and it doesn’t seem to be that. I saw a video about calibrating, so I calibrated the XYZ. Z was off 10.5mm on a 30.5mm check, so I adjusted the Z steps, tested again and got a precise hit. Stepped into carve mode and checked the Z using the homing buttons and had a precise check over 30.5mm.

Then reran the test cut, which still came out .228" deep when it was set in easel at .1" (test easel here: http://easel.inventables.com/projects/dPQVcEJCI1FqKzqa_jcPwg). I have NO idea what to do at the moment. Any help people have would be golden.

There’s a couple things you probably want to check:
-Make sure you’ve got it set in mm or inches.
-Make sure the wasteboard is flat. If it’s not, either flatten it or make a secondary wasteboard and flatten that.

Tests I ran in MM, cuts are done in imperial because my stock is, sadly it’s not that easy. The .28 occurs across the cut regardless of location on the waste board so it’s nearly perfectly level to the thousandth. :frowning:

I cannot give you the exact answer , but I can give you a clue, based on other postings I’ve seen. It looks like your depth is off by a factor of two. With the acme screw there is a two for one gear reduction. There are settings in gcode to set the steps per mm/inch for the axis. It is either the machine setup wasn’t done right, or you need to manually setup the value. I’ve seen posts that either redoing machine setup have fixed it, or that people have set the values manually based on observed depth of cut. Sorry I can’t be more specific, but a search may find out what you need, or call inventables and have them help you