Need travel consistency but its not working as expected <800 steps per rev too low>

[hivoltage]

I have a custom built system.
Centroid Acorn controller with clearPath motors. Frame is a Bulkman3d 1500x1500 using ballscrews 10mm pitch
I have read a lot on the forums to determine how to get consistent travel results.
I have used a spreadsheet from another user that helps with dialing in the turns ratio.
I am attaching the report and some screenshots.
When I am in the motor section I have it set to the values derived from a 20mm travel for the X axis (I am working with just the X for now)
The new values allow the dial indicator to read 20.00mm but in the system on the screen it shows 19.997. I used the MDI screen with the following command (g1 x20 f200).

I have searched for the correct way to do this calibration but all I seem to find are lathe ones. I do not have a lathe.
I used to use Mach3 and it did not show a value in the DRO other than what I wanted it to go to.
So I need to know what is wrong with my setup that is causing this. (NOTE: Sometimes it shows 20.000mm but its not traveling exactly 20mm according to the dial indicator.) I am going to see about getting a new dial indicator to rule it out. However my main concern is the interface not showing what was commanded.
Any help is appreciated.

I almost forgot to add the clear path motor parameters for the X axis.

[suntravel]

You have set up 9.8872mm / 800 steps = 0.012359 mm / step

So no way to hope the axis will drive with 0.001mm accuracy

The smallest increment the CNC can control with your setup is 0.012359mm

Related reading:

https://centroidcncforum.com/viewtopic. ... one#p11936

Uwe

[hivoltage]

@suntravel
I was not expecting that kind of accuracy.
Perhaps I am looking at this wrong.
Are you saying that the reading is what the machine does, but because of the accuracy being low it shows actual travel ?

[suntravel]

0.012359x1618 Steps=19.997

One step more would be 20.009

There is no way to drive to 20.000 and CNC12 is going as close as your setup allows

Use gear reduction or setup to a higher resolution.

Uwe

[cnckeith]

minimum steps per rev is 1600

read this post.
https://centroidcncforum.com/viewtopic.php?f=63&t=1801

[ShawnM]

Your motor are not setup correctly, read the doc that Keith posted and be sure to set the motors correctly and then change the settings in the wizard to match, Forget everything you know about Mach3, it'll save you some headaches.

[hivoltage]

Thanks everyone for the advice and info.
I will be getting things going after I get home.

[Gary Campbell]

Set your ClearPath motors to 3200 steps per rev

[cnckeith]

Set your ClearPath motors to 3200 steps per rev

and match that number in the Wizard!

3200 works. but, i use 6400 with most machines (even with the lower res 800 step clearpaths)

that's why the wizard set it to 6400 for either model (the 800 or 6400 step per rev model motor) it works with both for most all applications since clearpath can also run at 200,000 steps per second so there is no worry about running into a glass ceiling on top max rate for most all machines.
the Centroid smoothing algorithm likes hi step/encoder counts as well so you will get better results with that too!

[cnckeith]

https://centroidcncforum.com/viewtopic.php?f=63&t=8649