Well this is embarrassing......

Well this is embarrassing… Over the holidays I upgraded my ShapeOko2 to an Xcarve and I must say I am seeing better results. I did notice that the Z Axis movement was different. I chalked this up to switching to the ACME lead screw which is 12TPI. Well guess what I forgot to do? Change the travel setting for the Z Axis. :confused: The old setting was 1.25mm per rotation. I calculated the ACME screw to be 2.11mm per rotation.

However I am not totally sure I am right. The TinyG uses a travel per rotation. I did some measurements and it seems right my isolation cuts seem to be better because the Z head is traveling less per rotation.

Can anybody confirm?

Working on the math now. What micro stepping setting are you using?

8 since the all the NEMA17s that cam with the ShapeOko2 were 200 (1.8) with 8 for micro stepping.

So your old value was 1280 (right?) and your new value should be 755.79

That’s a substantial difference. Based on your pcb milling results I’m not sure on how you broke through all the copper if you weren’t going down far enough.

By upgrading do you mean you switched out all the mechanical pieces? Wondering if I should do the same.

Actually the original micro stepping per step was 4 so it calculated to 640.

Changing 2.11mm/Rotation and micro stepping per step to 8 gives me 758.293 or 15% reduction in the plunge depth?

Which I think is what I need. But again the TinyG ask for the mm per rotation not micro steps per step. So I think the 755/758 number is right.

The team at Inventables say the number should be 188.976 which comes in at 2 micro steps per step if using the GRBL controller.


I purchased the ShapeOko2 to Xcarve upgrade. It came with a better Z Axis Gantry and better X and Y axis plates. The X axis gantry plates center the weight better and all in all more rigid and stable. I notice an improvement. The motors, rails and gears stay the same. The Z motor is inverted and driven from a belt instead.

189*4= 756 so we’re at the right value.

The exact pitch is 2.117 so use the value with decimals I provided above.

Made the adjust as suggested and looks good. Thanks for the confirmation.

Most certainly. Can you mill another board? I’d like to see if there’s a discernible difference.

Sure I will mill one in the AM, I am curious how much it improves. I can tell just from the Z moves there is a difference.

I posted a quick video of the 3 boards I milled while adjusting the micro stepping. Check out and let me know what you think.

Started out great and only got better. Awesome results.