I’ve just finished my first MPCNC. The CNC works great overall - it’s easily controlled and square but all of my movements are too large by a factor of 1.25 (e.g., a 10mm movement is 12.5mm, 10cm movement is 12.5cm, etc.). I cut a perfect circle in acrylic, and it was 125% the size that it was shown in Repetier-host.
This includes BOTH the travel movements (via manual control in Repetier-host) and cut movements. I’ve doubled checked my drawing measurements, and they are preserved accurately in both ESTLcam and Repetier-host; only the physically cut pieces are too large. Any idea on what could be causing this, and how to fix it? I’ve reviewed my entire set-up and everything appears to be assembled correctly.
Parts were not bought from here, but identical parts were sourced from other places:
- Using NEMA17 48MM 1.68A (1.8 degree) stepper motors controlled by a Ramps 1.4 stack and DRV8825 drivers, that have been appropriately voltage adjusted.
- I’ve confirmed that the RAMPS jumpers are correctly in position beneath the drivers for 32nd stepping.
- There is a 100k Ohm resistor in the TO position on the RAMPS 1.4
- I’m generating my CNC code with ESTLcam, and controlling the MPCNC with Repetier-host following the guides from here.
- My Arduino/ramps has been flashed with the most recent firmware from here (https://www.v1engineering.com/wp-content/uploads/2017/05/MPCNC511_GLCD.zip)
Thanks for the help!