Nema 17 with planetary gearbox reduction (Marlin)

Using Arduino Motors, Mechanics, Power and CNC
1

Hi guys, I would like to aks some ideias, because I've exausted mines abut this.

For the Z axis I was using a stepper motor attached to some guide rails and was managed to get it working fine, but had to upgrade to a new motor with a 1:26.85 reduction gearbox.

The problem is, to any value of steps per mm that i put in from 50 to 2600 (the calculation of the correct value for this setup is 2600) I always get half turn on the shaft. Always the same movement for different step/mm value!

Is there any other setting in Marlin that controls this?

see specs here: link

I'm using Arduino Mega with Ramps 1.4 and Marlin firmware and full steps.

Settings on movement (note not using E movements):

#define DEFAULT_AXIS_STEPS_PER_UNIT { 3 , 3 , 2600 , 500 }
#define DEFAULT_MAX_FEEDRATE { 4000, 4000, 2000, 25 }
#define DEFAULT_MAX_ACCELERATION { 500, 500, 500, 50 }

#define DEFAULT_XJERK 5.0
#define DEFAULT_YJERK 5.0
#define DEFAULT_ZJERK 1.0
#define DEFAULT_EJERK 5.0

Thanks.

2

You may be lucky and someone who is familiar with Marlin may read your Thread - it would be good idea to mention Marlin in the Title. You can change the Title by editing your Original Post.

This Forum is really about helping people write their own Arduino programs. You may get advice more quickly from a CNC Forum or on the RepRap Forum where people are more likely to be familiar with Marlin.

...R

3

Thanks for the advice. Will do it for sure.

Cheers!

4

Seems to explain it in good detail.
In short you likely have a stepper motor that took 200 steps to do one full rotation.
Now you possibly have a 200 step motor rotating 26.85 times to get the output shaft to rotate one full turn or 5,370 full steps.

5

Slumpert:
3D Printer Firmware Settings - Stepper Motor Configuration | MatterHackers

Seems to explain it in good detail.
In short you likely have a stepper motor that took 200 steps to do one full rotation.
Now you possibly have a 200 step motor rotating 26.85 times to get the output shaft to rotate one full turn or 5,370 full steps.

Hi, I was on that website before. I will read it more careful again to check if I missed something. Thank you.