Well, almost perfect. It is within plus or minus .02mm or .0008".
I’ve posted it to Thingiverse:
Here’s a video of it in operation;
So I did a manual level and learned that the front two rows were off. The last row seemed ok. So I decided to put a Dial Indicator to it. I learned that the grid points were all over the place. So I tried manually tweaking the points using the “M421 In Jn Zn” command to input corrections to the grid. WORKS! Also wrote a couple of GCODE commands to do the check. One of them offssets the location to account for the distance to the Dial Indicator tip. The other one can be used to check with the test card delivered with the Snapmaker.
The sound isn’t great. Give me any feedback you might have.