Steps per inch calculation

I’ve been putting way too many hours in at work the last week or so but was able to get my xcarve going and tuned a bit tonight. Ive been struggling with the steps per inch in a bad way. I just finally got it accurate using the Mach3 steps per unit configuration tool in inches, using 1 inch increments.
Now that Its running and seems accurate…the steps per inch numbers/math aren’t making much sense to me and would like to know why. No microstepping involved (controller does it automatically), just base steps per inch…these are my working settings with gecko g540 driver…
X and Y = 1270
Z = 24190
It’s working, I’m happy, but concerned about not having been able to do the math and been close without using the mach3 utility. Any insight is more than welcome, and thank you :slight_smile: Tim

Hmmm. Mine came out to 127 steps per inch. But the z gave me trouble. I had to experiment similarly and used a dial gauge with dozens of movements to dial it in. I used this page to do the math initially:

See if this helps: http://www.shapeoko.com/wiki/index.php/Grbl_Configuration

You have to translate between mm and inches.

My Z is 38412.88746 at 1/8 which would be: 4801 (4800) at full step. Your Z figure seems to be almost exactly 5x that and your x and y seem to be exacty 10x mine. I am guessing your Gecko’s are microstepping.

Even so, our numbers are very very close - just off by an indentifiable, round number factor.

As soon as I get a chance, I am going to reset mine to 4800 x 8 or 38400 and I suspect it will be perfect. Just like your z is PROBABLY actually 24,000. You might give that a try.

Hmmm. Thanks for the reply and the link. I didn’t even take into consideration the driver micro stepping while using the Mach steps per utility. Hopefully I can get a chance to look at this after work tonight