Z-height problem while printing PETG
Hello,
I was printing PLA(210/50) without any issues for more than half a year. Now I switched to PETG(230/60) and have huge problems.
I have MK2S with PINDA without thermistor. Due to higher bed temperature I first do the mesh bed leveling while cold, home the nozzle and then heat up the bed/nozzle not to disturb the PINDA measurements
With PLA I had live Z -440um, after few calibrations for PETG I ended up to 0um and the result was:
The result is as seen, the nozzle at printing intro line was so close that it did not print it completely..
I then set to PINDA probe little bit lower, since 0um was not enough..
Manual says that the distance of PINDA should be as the height of a middle part of zip tie, I did it as the end of zip tie (~1/2 lower)
I did the XYZ calib. in the room temperature
The result is as follows:
Can you please help me explain what the heck is wrong?
I calibrated XYZ while PINDA was cold, did the mesh bed leveling before print while PINDA was cold.. does my heatbed bend while it's hot?
Re: Z-height problem while printing PETG
does my heatbed bend while it's hot?
Yes. The bed is constrained at the screw points to a (not hot) mount. As it expands with temperature, it will bend and warp. This is why the Z calibration is done at the beginning of the print with the bed at temperature. The XYZ calibration is really for skew and non-parallelness. It can be done cold.
It is normal to need a different Live Z for different bed temperatures.
Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage or loss. If you solve your problem, please post the solution…
Re: Z-height problem while printing PETG
You're so right! Thank you.
I tried the Z calib. while bed is hot and it's perfect now 😆