X-Y and Z actual movement

[Turner]

Hello everybody,

For my new Rostock Max (first printer!), after much trial and error, I am stumped and would appreciate any help!

My X-Y movement and Z movement are not scaling correctly. I first began comparing the actual movement of the head vs what I tell it to move in Repetier. For example, I would set it at Z5 Y80, zero in the y azis with a pair of calipers, tell it to move to Z5 Y50, and compare the actual to theoretical movement. The computer says that it moved 30mm, while the calipers measured 45mm. I adjusted the motors and now the XY movement is exact, except it screws up the Z movement.

If the XY movement ratio is 1:1, then the Z axis is at about 1:0.6 (theoretical:actual)
If i adjust the Z axis to 1:1, then the XY is about 1:1.4

I am running Polygonhell's firmware.

Any direction or help would be appreciated! Thanks!

[Broose]

Not sure is this is your issue since it seems like it should affect all three axes, but do you have a newer machine with the 20 tooth plastic timing pulleys on the steppers? If so, you should make sure your Configuration.h file has
#define PULLEY_TEETH 20
and not 15

[Turner]

Oh thanks! I forgot to change that. Would changing the steps/mm motor settings be equivalent to changing that though? Or would that bypass cause additional problems?

[Broose]

Yes, they are both related, but there was just a post that the correct steps/mm should be set in BOTH the EEPROM and configuration.h. Apparently the configuration.h setting affects the Delta motion, which could be your problem. And PULLEY_TEETH controls the effective steps/mm in the configuration.h, so it could affect the delta motion as well. See Polygonhell's post:
http://forum.seemecnc.com/viewtopic.php ... 7&start=10
-B