plucky jay
My 350 2.4 has had high Z backlash for a while. It still prints well but sometimes fails QGL (from the movement of the numbers it seems it passes by luck, and helped by the fact that my QGL macro doesn't lift once it reaches <1mm error so the backlash is minimized. With the regular macro it probably doesn't pass) and you can easily reproduce it moving the gantry up and down with the steppers. I'm measuring it with beacon's BEACON_ESTIMATE_BACKLASH, and depending on the corner it's between 0.025 and 0.035. Here are the things I've checked so far:
- Z drive assembly screws are all tight
- The screws that secure the Z drives to the frame are tight
- All 6 grubs screws in each z drive are tight
- The belts between the z drive motor and the main drive shaft are properly tensioned
- The Z idlers have been changed for BZI and tensioned both at stock and increased tension
- The Z belts are properly secured to the gantry and all the screws in the gantry are tight
- There is no rubbing of the excess belt against panels ( in fact panels are off right now )
- The screws that secure the Z joints to the vertical linear rail blocks are tight and the rails are tightened to the frame.
- All the blind joints in the frame have been checked to be tight
- The toolhead is rock solid and there is no play whatsoever in the probe itself. Everything in the gantry is tight. I'm using monolith but the backlash is from before.
- Ran through my z stepper config and updated it with latest base config ( I still had hold current in there )
Edit: - Bed is tighened to rails. Bed rails are tightened to frame.
What haven't I thought of? What are the odds my belts could be the issue here? I don't have spare 9mm belts to try but i do have new 6mm GT3 I could try just to diagnose (Edit: already tried).
Thanks a bunch!