Hi guys
Vasili here!
I face a problem with Mach3 and i explain: I recently rebuilt a ISEL CPM 4030 milling center ( setting the soft limits in X 38.00 Y 30.00 Z 16.00 ) with new 5 axis breakout board, drivers and so. Setting up Mach3 whas a little bit trickie while the motor connection of the actual milling center was CHAOS! I had to isolate so many cables to make it work! Anyway, it work perfectly and accurately but in reading G code file!!!!! It reads in CM instead of MM and it moves beyond its machine coordinates. Even the soft limits setting are in CM!!!!
This is the reason i'm asking for your help!!!!!!!!
I use Freemill as a CAM.
Any suggestion would be very appreciate!
Thank you all in advance
Vasili.

Sounds like your axis steps per unit are set incorrectly.

Try the Axis Calibration feature on the Settings (Alt-6) page.

Tweakie.

Thanks for your quick reply Tweaky!
The axises move accurately.
If i set 10, it moves 10 Centimetres accurately! This is not the main problem!

Set your steps per unit to mm, so if you command a move of10 mm it moves 10 mm and not 10 cm.
You can also use the axis calibration feature in the flyout ( lower left corner on the screen) after using the Alt 6 tab.
 
Don't know anything about Freemill, but, if it matters, draw /create in the units that Mach is configured for.

RICH

Rich and Tweaky !!!!!!!!!!!!! You're absolutely right!!!!!!!!!!!!!!!!!!!!!!!!!!!!
When i typed 10 in axis calibration and the axis moved to 10, it was actually 100 mm's! I couldn'd figured out that was 100 mm and not 10 cm's!
Thank you very much!
But tell me something else please: When i put G0 X10 in MDI , then it moves 9 mm's and not 10! What's going on here?
Thanks for the reply  

I solve this too!!!!!!!!!!!!!!!!!! Thank you guys for helping me! I really appreciate!
Vasili

Excellent 

Tweakie.

I am having the very same problem - instead of moving 1mm my machine moves 1cm.

I know how to change between mm and inches but I don't know how to make it mm instead of cm.

It is set to mm already....

Do I need to re-calibrate my machine again?

Hi,
yes, there is no 'cm' setting in Mach, what it means is your 'Steps per Unit' value in the motor tuning pages is out
by a factor of 10.

Try getting this info:
1) The lead screw pitch, needs to be accurate, 'about 1/4 per turn is NOT good enough, real accurate,from manufactuers
     documentation preferred.
2) Belt or gear reduction ratio, if fitted, between the stepper and the lead screw.
3) Your microstep setting of your stepper drivers
4) I assume standard two phase stepper of 200 step per revolution?

Craig

Re-calibrate your machine.

Use the Set Steps per Unit calibration feature (Settings page) - follow the on-screen instructions using the largest measurement distances you can.

Tweakie.