Failing PETG since recent updates
Hello,
Do'nt know what is causing the problems but suddenly met PETG-printing is failing HARD.
filament won't stick to the bed.
Updated SlicerPE en did the Firmwareupdate yesterday after returning from 14 days of holliday
using Prusa PETG, recently bought and dry stored
! IMPORTANT: ATM is it is rather hot weather over here so room-temp of 27 degrees Celcius
... So i tried changing added cooling via fan
tried less hot nozzle and bed (about 5 to 10 degrees less)
using original MK3 settings and Prusa-Petg-settings
Things I tried and tested ...
Calibrating first layer, full wizard, temperature
Cleaned PEI-bed, with water, witch soft soap, with dishwash-soap, with Acetone (once)
using coat of hairspray
changed Z-live from original -300 to -250, to -275, to -300 again ... and noticing squached layer.
with -300 nothing is getting out of the nozzle, it seems, with -250 it floats over the bed and does not stick, warps upwards.
when slicing with Cura and Prusa-settings integrated, I get sticky first layer but quality is RUBBISH.
Tried...
and all that time my good old AM8 is printing slow but nicely with slightly less quality but with same material.
help
...
Should i go back to previous firmware?
Re: Failing PETG since recent updates
Seems I fiiiiinaly got it better (do not want to use the word "solved" :S )
again: problem: new updates, high ambient temperature, PËTG not sticking on fist layer, warping, ... (something I NEVER experienced before, while using the standard procedures and trics)
I went to new nozzle (but the old one (hardened st prusa (E3D) 0.4 nozzle was inspected and seemed perfect ok)
(so new calibration first layer!)
ALSO changed live height from -380 to -420 .... which I do NOT understand asPETG needs a higher height then PLA, but what really made a difference was changing bed-temp to 76° Celcius.
my findings, hypothesis: the high room-temperature makes, keeps the filament too long in a liquid state so that the filament can bend, warp ...
A higher difference in temperature between filament and bed is needed to "fix" the filament to the bed, (before it has the chance of warping, bending, ...)
What also helps is a nozzle that is pushing the filament against the bed ...
At the the same moment, I guess that could also be helped by adding fan-function on the fist layer, which seems completely logic .... but i have tried that and got not change in problems ..
... so your guess is as good as mine.
Re: Failing PETG since recent updates
addendum: the second layer does not seem to have all these warping-problems; sticks perfectly to the first layer
I had tuned the temp to 76 for the bed but as the MK3 is now using the "rest-of-the-layers"-settings it has now switched back to the standard prusa-settings.
Live layer height is STILL -420.
Re: Failing PETG since recent updates
The two most common reasons for your problem are the wrong Z level and a dirty bed.
In your case, I would recommend washing the bed with detergent and water.
Acetone and other chemicals do not help.
Bear MK3 with Bondtech extruder
Re: Failing PETG since recent updates
The two most common reasons for your problem are the wrong Z level and a dirty bed.
In your case, I would recommend washing the bed with detergent and water.
Acetone and other chemicals do not help.
Mmm, as said before ... I cleaned the bed with soft soap: no improvement, with detergent: nope, with acetone (As explained by Prusa!), with a brush, ... noperdenope
and about Z: I calibrated the printer ceveral times
Re: Failing PETG since recent updates
some people don't recommend this anymore, but light sanding with #0000 steel wool helped me out a lot.
didn't see if you mentioned this, but there's no shame in taking your first layer settings to the extreme. go much hotter and slower and see what happens. I routinely use 260 nozzle and speeds <20mms for the first layer. Also, a taller/wider first layer can help sometimes.
Re: Failing PETG since recent updates
If cleaning of the bed did not help, then the Z level you are going to work with.
-300, -275 and -250 are very large steps in calibration.
When fine-tuning the Z-level, I use steps with 5 or fewer units. Then start calibrating at -300 and lower Z level 10 units at a time. When it starts to look great, you reduce the steps to 5 units or less until your result is perfect.
And before you start, perform the Calibration/Calibrate Z menu selection (not XYZ).
Bear MK3 with Bondtech extruder
Re: Failing PETG since recent updates
some people don't recommend this anymore, but light sanding with #0000 steel wool helped me out a lot.
didn't see if you mentioned this, but there's no shame in taking your first layer settings to the extreme. go much hotter and slower and see what happens. I routinely use 260 nozzle and speeds <20mms for the first layer. Also, a taller/wider first layer can help sometimes.
Hello, did not mention it but indeed also did light sanding with steel wool.
Also, I tried to tune Live Level in tiny steps, as 5, ... but mentioned the values I ended up with.
Anyway, I've read some good tips here:
trying with slowed down first layer
testing with coller and warmer nozzle and bed
and I'll try that Z-calibration, in stead of the complete XYZ-calibration. Can't harm
Update though .... yesterday-evening temperature dropped below 28° Celcius .. and PETG is now printing fine again.
The MK3 is on basic settings again as I always try to get it back to STANDARD settings when testing things out.
Re: Failing PETG since recent updates
When fine-tuning the Z-level, I use steps with 5 or fewer units. Then start calibrating at -300 and lower Z level 10 units at a time. When it starts to look great, you reduce the steps to 5 units or less until your result is perfect.
For first layer calibration, I just fold a sheet of photocopy paper in half, start "first layer calibration without any filament and while "printing" wind down the Live Z Adjust until the paper is slightly gripped. Doing that you will get to thereabouts 0.2mm layer height in just a few seconds.
Any tweaking is then carried out with the first layer of a model.
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: Failing PETG since recent updates
For first layer calibration, I just fold a sheet of photocopy paper in half, start "first layer calibration without any filament and while "printing" wind down the Live Z Adjust until the paper is slightly gripped. Doing that you will get to thereabouts 0.2mm layer height in just a few seconds.
It was a really good tip to quickly find the right Z level!
Bear MK3 with Bondtech extruder