Notifications
Clear all

Help printing PETG  

  RSS
chris.h4
(@chris-h4)
Active Member
Help printing PETG

I got a roll of eSun PETG white, I've been trying to print with but I can't get it to stick to the bed. I can't figure out what is wrong. I've gone through calibration of extruder/flow, xyz, pid, etc.. I set the extrusion multiplier in slic3r to .95 and still the filament just rolls off the bed as the extruder goes about. It also oozes out of the extruder while its warming up. I've tried lowering the temps to 228 but it only slows slightly. Is this typical?
My PLA prints are great, but PETG is proving tougher than ABS. I was able to get a 40mm round disk to print OK, the perimeter got pulled into the first layer but it didn't grab hold. The filament seems to want to attract to the hot end curling upwards and blobbing up. If anything on the first layer is sticking up it will grab it and tear it up.

I'm sure I just don't have the settings dialed in slic3r, or maybe there is some other problem? Maybe if I could get it to retain its tackiness while stopping it from oozing out of the extruder? I'm out of ideas on what to do and need some help.

Posted : 31/05/2017 8:51 pm
philip.g5
(@philip-g5)
Eminent Member
Re: Help printing PETG

It is funny because I do not have my i3 yet so I do not know how well the PEI works but others have reported incredible if not too much adhesion to the bed when printing PETG. In some cases they are using baby powder or glue sticks as medium to allow them to take the print off. In your case I would bet that the bed is covered in oils from touching it. Have you tried to clean the bed thoroughly with IPA and Acetone?

Philip G.
Original Prusa i3 MK2S
Turnigy Fabrikator Mini

Posted : 31/05/2017 8:55 pm
GertL
(@gertl)
Reputable Member
Re: Help printing PETG

Hmm, PETg usually sticks like hell on the PEI.
I print almost only PETg, using eSUN.

I clean my bed with IPA and then i swipe it off with Windex (Blue window cleaner) to make the PETg not stick to hard.
Temp 240/80, no fan for first layer then 50%.
Speed 40mm/s with first layer at 40%

I get nice results with eSUN PETg. Almost no stringing at all.

Not the best picture

---
Gert

Posted : 31/05/2017 9:03 pm
chris.h4
(@chris-h4)
Active Member
Topic starter answered:
Re: Help printing PETG

haha Philip, it is funny though thats why i'm soo fustrated. Everyone is like, get petg, its like pla and abs combined, easy street. Just not for me haha..

Gert, That looks great! I'd be happy with that, funny too cause I was just going to make some mods to mine and print them wondering if they'd be good in petg. Glad to see someone printing successfully in eSun petg.

My bed is kinda hazy from printing in abs even after I clean the crap out of it with %90 alcohol. I thought maybe it does have some resedue on it so I scrubbed it hard a few times with acetone and tried again. I also backed the filament out of the extruder 3 steps to keep it from oozing, that seemed to stop it before the print start. At least the first layer is sticking but its awful shaggy looking and detail around lettering is so so. My current settings are 228/85 no fan first 3 layers .95 extruding multiplier. Wondering if i should extrude more, but i'm trying to get rid of the frazzle, stringing... Here's what it looks like:

I'll try your settings Gert after I let it go for a bit, but what about ext. multiplier?

Posted : 31/05/2017 9:38 pm
TFMvdBroek
(@tfmvdbroek)
New Member
Re: Help printing PETG

Yeh you should probably go up in temp like ~235 on the nozzle and 65 on the bed.

Posted : 31/05/2017 10:09 pm
philip.g5
(@philip-g5)
Eminent Member
Re: Help printing PETG

Chris, After looking at those pictures I can tell that the first layer is not being pressed against the bed enough which in turn causes the line of filament to be very thin and rounded rather than slightly squished. I would try lowering the nozzle slightly to the bed using Live Z adjust.

Philip G.
Original Prusa i3 MK2S
Turnigy Fabrikator Mini

Posted : 31/05/2017 11:56 pm
JoanTabb
(@joantabb)
Veteran Member Moderator
Re: Help printing PETG

however squishing the first layer will make it stick harder, so consider one of the pei adhesion reduction methods....

either, dust the heatbed with talcum powder and wipe all that you can, off again... (the method use)

or use gluestick as a bed surface alternative, sort of sacrificial interface.
or use forehead grease, smeared across the surface... never tried this...

best of luck.

Joan

I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK

Posted : 01/06/2017 12:13 am
chris.h4
(@chris-h4)
Active Member
Topic starter answered:
Re: Help printing PETG

I restarted with 240/80, 1.0 ext. multiplier, %40 speed first layer, and I did a live z adjust down another .1 to squish it out more like suggested. Retracting the filament a few clicks before I start print really helps with that oozing. I'm able to get a much cleaner start now. My nozzle had a lot of burnt plastic on it that I cleaned off with soap. Though it wasn't hanging down into the print or anything, it seemed to help keep the plastic that was layed down from wanting to attach to the nozzle. I guess it was just a lot of little things. My prints not done yet but its looking a lot better. One question, why does it look like i'm only getting 1 layer down before it starts the infill with that honeycomb pattern. I have my horizontal shell set at: bottom layer 7 layers, and top to 9, like default. There's no way thats 7 layers? Also, Does live-z adjust save for any future prints no matter what gcode i'm running, right? or does it only save if I run v2.calibration?

Posted : 01/06/2017 2:28 am
Share: