Calibrating a Mini Kossel

Dave Parry

I'm trying to calibrate my mini kossel, using the Duet3D guide.
I get through it all ok, but if I home the carriage and re-do the calibration its always out, ususlly X=0 is too high. I've tried sending M500 before homing no difference.
How can I get it to keep its calibration?

dc42

Are you using M501 at the end of config.g? You need to do that for your changes saved using M500 to take effect when you restart.
Are you calibrating with the bed and hot end at stable temperatures? Because deltas home to maximum, the Z=0 position may vary if the temperatures are not stable.
If you are calibrating with the bed heater on, have you allowed it sufficient time for the temperature to stabilise across the bed? It's not uncommon for bed plates to warp with temperature. Depending on the placement of the bed thermistor, it may take several minutes for the bed to reach full temperature even after the thermistor reports that it has.

HTH David

Dave Parry

@dc42 Hi David, thanks for the reply, sorry for delay but been busy and not able to check your recommendations,
1 Yes I have 501 at the end of the config.g
2 the bed temp is stable, but will check again.
Will give it a bit longer to stabilise.
If the tips dont work, I think I will reload the software.
I did have a problem at the end of a print when the panel duo suddenly went haywire and had garbage on the screen. I had to reload its software, so maybe the Duet was also corrupted in some way.
What I have noticed is that the calibration is always at -1.05 after homing.

Dave Parry

@dc42 David,
Got it working.
in the end I did a auto calibrate and that sorted it. Should have tried that first.
Anyway thanks for help.