Issues with bed adhesion using PETG on A5S

Kenneth Lloyd Boller

I have been trying to print with PETG on my new A5S for days now.

ive been googling about and trying every setting suggestion i can find but still cant get my first layer to stick to the bed, im using Cura as my slicer program (tried kissslicer, didnt like it) and the only time iv been able to get anything to print was using the default "Draft" setting for PETG right after leveling the bed again and again and again. i printed 2 puzzle pieces as a calibration to see if they would fit together, before i printed my real project...they didnt

so i changed the horizontal extension (and nothing else!) and now cant get anything to print at all cant get anything to stick to the bed, PETG sticks to literally everything BUT the print bed, ive cleaned the print bed with water and alcohol but have not tried using glue sticks or blue tape or hairspray yey, id honestly rather not unless its absolutely necessary.

i bought PETG cause from everything id heard it was like a better PLA and i had good luck and got alot of cool prints off with my PLA spool that came with the printer, this is my first printer im a huge noob at all this but I think im learning as i go slowly but surely but after a couple days of not getting anything to print and trying everything i can think of its getting very frusterating when all my nozzle wnats to do is spew strings that just dance around off the bed and im at my wits end with it so that brings me here to ask all of u nice people for even more suggestions.

heres some of the things iv found in my googling about that ive tried so far

https://jgaurorawiki.com/a5/bed-adhesion

https://jgmakerforum.com/discussion/296/petg-unable-to-print-a-perfect-object

https://jgmakerforum.com/discussion/616/petg-printing-a-lot-of-frustrations

i also thought maybe i wasnt getting the bed leveled good enough because everytime i level it i never know whats too tight and whats too loose with the sheet of paper, should it be a very slight friction or a proper scratch? iv leveled it more times then i can count both cold and hot both and finally resulted to trying this mesh bed leveling thing i keep hearing about

So i upgraded the firmware today and after i saw the display of this community firmware was no where near as pretty as the factory i wanted to put it back but cant figure out how but thats a separate issue entirely, I finally gave up on trying to revert the firmware back today and decided to just move forward with doing the mesh bed level thing and iv done it like 4 times now again cold and hot both and still nothing is sticking.

never buying another roll of PETG again...ill stick with PLA
...get it? 

I really really just hope u guys can give me some new suggestions that i havnt alrdy tried or thought of yet, again im a huge noob at my whits end and i just want to print

[img]https://i.imgur.com/U1uCvXe.jpg[/img]

[img]https://i.imgur.com/44dSRdn.jpg[/img]

Kenneth Lloyd Boller

[img]https://i.imgur.com/jcUdBUs.png[/img]

found this, gonna try it without the glue first just flipping the bed and taping it and if i still dont get a stick ill glue it.

would still much appreciate any additional ideas settings or suggestions tho please.

thanks in advance guys.

Kenneth Lloyd Boller

flipped the glass, cleaned it, and blue taped it, no stick, remove the tape and tried again no stick

re-mesh leveled the bed with nozzle at 240 and bed at 100 still no stick
tried again with a Z offset of -.2 still no stick
tried again with a Z offset of positive .2 still no stick
re-leveled the bed again without being heated up tried all of the above again,
still... no... stick...UGH!
really beginning to hate PETG but i have 2 giant rolls of it that i need to use up now or else ive just wasted my money on them if i cant use em
someone...anyone...please help me
im a noob in desperate need of a guru.

Kenneth Lloyd Boller

[img]https://i.imgur.com/qboVLfX.jpg[/img]

think i might finally be getting somewhere...i put the blue tape back on but apparently bed temp was too hot? i used the preset "Draft" setting in cura and only changed bed temp to 65 and nozzle to 250 and we finally have adhesion.

Kenneth Lloyd Boller

just gotta hope they fit together now...but atleast were printing something and not just flinging strings

Kenneth Lloyd Boller

got the puzzle pieces printed, printed about 2 or 3 sets, had to baby step the horizontal expansion to get em to fit together just right and after i got that i went on to try to print my next part with the exact same settings and im back to no adhesion...
cant believe over 50 people have viewed this in the last 24 hours and yet im here talking to myself with absolutely 0 help or response...

aestrems

Hi,

Happy to see you found a kind of solution to your problem, I'm not an specialist on PETG and what I heard a lot of people is having this issue with the bed adhesion and most of them they use a spray/glue for PETG to keep the object on the bed. 

Sorry if 50 people viewed your post without leaving you a comment but some people are not using PETG or they have the same issues as you and they enter just to see if you can help them, and also possible those people are beginners and they can't help you. Hopefully others will post a comment with their experience with PETG

The good thing is you made all this steps and your experience may help others. So please let us know more about your PETG problems, many thanks to share your problems with us

rhaub101

Here is what I use for petg:

Use good PLA setting and make these changes.

A: Level the bed good with a sheet of paper with the nozzle at 245 and the bed at 70.

B: Print temps 245/70

C: Spray the bed with Aqua Net hair spray. (I use hairspray for ALL filaments)

D.  First layer print speed = 15mm/sec

E: Print Speed = 30mm/sec

Hope this helps

Samuel Pinches

@Kenneth Lloyd Boller  Welcome Kenneth. Sorry, I'm not on here every day.

PETG is not a perfect material. 100 on the bed is definitely far too hot. What are your current settings for nozzle and print temps? Whats your first layer print speed and first layer fan speed?

When you change printing materials you need to clean the bed thoroughly as the residue can make it hard for a different material to stick..

Kenneth Lloyd Boller

seemed to be kind of a part by part basis with PETG as posted above i was able to get 2 or 3 prints off of the same part by flipping the bed blue taping it and changing the bed temp down to 65 but using these exact same settings trying to print my next part i had no adhesion to the bed again. I didnt change speeds at all but the changes i did make, one by one, per the suggestions i found thru googling, to try to get it to stick, are as follows

tried changing nozzle temp to 250
bed temp to 100
fan speed to 80%
brim of 20
initial layer height of .3mm
flow of 96
initial flow of 94
retraction distance of 4
tried enabling z hop of 1mm
tried putting in all sorts of z offsets from -.2 to +.2
and still no adhesion

probably leveled the bed like 20 times hot and cold and somehow, someway finally got my finger pieces to print and i honestly changed the setting so many damn times i couldnt even tell you what settings i used to finally get it.

yesterday my Black PLA came in the mail so i unload this White PETG and tossed it to the side, ill want to use it up eventually but right now im done screwing with it.

below are the "Draft" default settings for generic PETG and the only change i made to these settings was knocking down the bed temp to 65 and that seemed to work best for the most part.

[img]https://i.imgur.com/RwVPmmr.png[/img]

[img]https://i.imgur.com/9mCcZs2.png[/img]

[img]https://i.imgur.com/Crib6iJ.png[/img]

[img]https://i.imgur.com/tiBZtK4.png[/img]

still need some help and have some questions about the firmware but i may make another post for that later on, i rly dont like the looks of ther Merlin community firmware but the bed mesh leveling is a rly cool feature of it so im undecided.

thanks for the responses guys sorry for seeming a little snappy and salty on my last post PETG was just getting on my last nerve and was becoming very frustrated with it.

Samuel Pinches

The black diamond coating requires patience and care to work with reliably. You read my bed adhesion tips on the wiki? You're doing all of those?

I know the firmware interface sucks. Its the best we could do with the resources we had - I've had very few volunteers to help with firmware. Marlin touchscreen interface is just getting started, it's going to get better eventually.

I understand the frustrations. Sometimes good to take a break from 3D printing when things get frustrating. Often there's more than one problem that needs to be solved.

Laser8302

I have been printing successfully with PETG for a bit now. I see you read my thread. I spent weeks/months trying to figure it out.

Bed adhesion:
HAIR SPRAY on the black diamond coating is best.
Keep your first layer between 15-20mm/s and always around 0.25 to 0.3mm
bed temp between 75-85ºC

Extrusion issues:
Make sure your heat break is properly connected to the heatsink and the heatsink has proper airflow. Use a bit of anti-seize or thermal paste when you insert the heat break into the heatsink. Make sure your nozzle is properly tightened.

Cooling fan:
Not more than 50% fan required for PETG. It doesn't like to be cooled too much unlike PLA. (Crank your cooling to 100% for everything above the first layer for PLA)
Make sure your fan is at 0% for the first layer.

Extrusion multiplier/flow rate:
Set this to 105-110%. PETG is a softer material than PLA. Your extruder was calibrated for PLA. PETG will "squish" when passed through the extruder so you need more flow in order to get your extrusion right. (Or calibrate your e-steps for PETG)

If you have a way to dry your filament, do it. PETG absorbs water from the air. I bought a food dehydrator and put my PETG in it for ~2-5hrs before printing. I also store all my PETG in a air-tight container with the desiccant packs.

PS
when I went to the BMG extruder my extrusion issues went away. I highly recommend a geared extruder over the stock one.

Kenneth Lloyd Boller

Very cool! thank you so much for your response, alot of info there but thats exactly what i needed i will def try all of this when im rdy to try printing PETG again.

MarkMarcum

what is a BMG extruder? and where can i get one?