The nozzle clogs after certain Z height
Hi,
Our Prusa mk2S MMU worked fairly well but now, no matter what, after aprox. 5 mm height of almost (?) any object we print (we use PLA) the nozzle clogs gradually and in several seconds the nozzle is completely clogged (no filament is extruded anymore).
Any idea why?
Settings:
Temp: 220
Bed: 60
Retraction: 7 (we tried with 4 also but no luck) - with 7 we worked fine for almost a year.
We changed different parts from the hotend but it didn't work. See the attached document for details:
Re: The nozzle clogs after certain Z height
7mm retraction is probably required because the temps are way too high. That retraction will cause clogging.
You need to aim for about 205 degrees for PLA and 2.5 to 4 mm retraction, but that depends on whether you have LA working and correctly tuned.
You may also have wear in the PTFE tubing or your nozzle may need replacing.
Peter
Please note: I do not have any affiliation with Prusa Research. 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…
Re: The nozzle clogs after certain Z height
Thanks!
Will try.
LA is the default Slic3r value (100 mm). Do you think that it is safer to just disable it?
Re: The nozzle clogs after certain Z height
LA is the default Slic3r value (100 mm). Do you think that it is safer to just disable it?
No, I think it best that you calibrate your filament to work with it. LA can significantly reduce the retraction required and therefore reduce blockages.
Peter
Please note: I do not have any affiliation with Prusa Research. 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…
Re: The nozzle clogs after certain Z height
Found it!
It was the nozzle.
Next question: Our old nozzle is/was an Olson Ruby. How can we „clean” it to use it again? I think that it was semi-clogged by „something” which built up over the years inside. We printed PLA and HDGlass (FormFutura's PETG offering).
Re: The nozzle clogs after certain Z height
Our old nozzle is/was an Olson Ruby. How can we „clean” it to use it again? I think that it was semi-clogged by „something” which built up over the years inside.
No idea, but when a nozzle needs to be replaced, you should really really replace it (which is why I run standard brass nozzles - I don't have the temptation to use them when they should be replaced).
Peter
Please note: I do not have any affiliation with Prusa Research. 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…
Re: The nozzle clogs after certain Z height
we have similar problems, but i dont understand whats written here...
what is "LA "??
Where/what is retraction?
"yes we found it, it was the nozzle" Great, but what did you discover about the nozzle?