I print PETG successfully with SM2 and the parts look good. What I’ve found is the first layer looks rubbish, often has a lot of bobbles etc, but by the 2nd or 3rd layer it doesn’t matter and in the finished print you can’t tell the first layer was so bad. I’m using this for functional parts, pipe fittings etc that need to be accurate and getting good clean results.
I’m printing at 225c, first layer at 230c. A hotter nozzle strings a lot.
Bed at 80c, then down to 70c after first layer.
Retraction distance 4mm, speed 55mm/s
Initial layer speed 15mm/s then up to 25-30
Travel speed 80mm/s, may be this should be slower but works for me
With enclosure and enclosure fan off
Print head fan reduced using Marlin code M106 S128
Ok, I admit, occasionally I’ll pick off a bobble in the first layer if its big with tweezers.
I hope this is helpful for you and gets you printing PETG.
I just wanted to say its like printing with puppydogs and rainbows.
Still need to work on the stringing a bit but wow does this stuff lay nice and easy and comes out GREAT! Even the stringing is like peach fuzz, so soft and easy, i could shave it off with a disposable bic razor.
Part of my success might be from my new glass bed (pyrex) with magigoo to protect the glass from getting ruined by the petg.
I am currently working on some new clips so i can put the PEI sheet over the glass to see if it prints as well on that.
Honest to god, I had no crumbs or garbage from this material, it was like using PLA.
You probably won’t ever get rid of the light stringing with PETG. Only really hope to reduce it but at that point it disappears easily with heat gun (some have said just with hair dryer)
PETG is mu
If you need a little flex in an object PETG is the way to go. I tried both PLA for some bag clips and the PETG works great without snapping. If you’re slicing with cura using gyroid infill works well for strong and flexible. Play with infill % from 10-20%
I finally found good results with 230 nozzle temp, 80 bed temp, and 0.3 initial layer. Prior to the 0.3 initial layer, I scrapped every attempt. Don’t give up, this hobby, while frustrating, will make you a little smarter every day.
If you’re saying that you should calibrate the same way every time (whatever method you use whether it’s the card with pull/can’t push or same resistance for push & pull) I agree. If you’re consistent in this it will help immensely. If you’re saying that every type of filament needs the same z-offset, that’s not correct. Some filaments like tpu tend to need more squish, while PLA is a little less and PETG the least. All this can vary between brands.
It’s not that susceptible. Maybe if you live in Florida. I’ve had no problems having mine out for multiple days of printing. I always store it in an airtight container with plenty of desiccant. Of course I’m in southern California with no humidity. Now nylon, that’s another story.
Could be the roll of PETG. I have had rolls that no matter what I try will not stick to the bed.
Better off returning the roll or just try a different brand. I have had great luck with the Overture Brand PETG and PLA sold on AMAZON.
One more thing. PETG does not like to be squished to the bed like PLA. When I print PETG at say .2 - I set the z offset to just around .2 or ever so slightly less. All my PETG is printed on glass bed printers. I need to order one for my a350. If you do use glass make sure and put a substance to keep the PETG from becoming part of the glass. I use kids purple glue stick. I have forgotten to put down glue stick and had to replace 2 - 3 glass print beds. You do get awesome glass like first layers without the glue stick but it’s not worth the risk.
I just started using pyrex glass - i put some magigoo down cuz i heard about that problem.
Im really impressed with how its going. i have almost my whole bed filled iwth parts now, but i lost whats in the lower left corner overnight (i shoulda started the print over i was tuning the z offset) definately the most of the sheet ive used so far
That’s exactly what I was questioning and I disagree. On some filaments, tpu especially, you need some squish and a lower z-offset - independent of layer height. On PETG you may need less.
My SM is in my garage so I’m not dealing with humidity problems and have had translucent PETG out while printing for a week and a half with no effect. When I lived in Pacific Beach my towels never really dried out. Or maybe you’re getting filament that already has some moisture.
Did my first PETG print on SM2 yesterday - no prob’s whatsoever. Print bed @80°C, Nozzle at 220°C, nozzle calibration just the same as with PLA. Used FormFutura HDGlass, i.e. transparent, food safe certified PETG. The spool is already rather old (~1 year), and was stored in a plastic bag with desiccant, but not really airtight - no problems with moisture. I was concerned about how hard it would stick to the bed. I printed PETG on my old printer directly on glass, and my happiness how well the first layer adhered to the glass turned into horror when I tried to get the print off - I literally pulled small chunks of glass off with the print, ruining the one side of the glass. So I put some hairspray on the SM2 bed, and the print came off totally easy from the still hot bed. I let it cool down a bit on the still warm bed to avoid warping.
Question: Has anyone ever had problems to get PETG off the SM2 bed without using any seperation layer like glue stick or hairspray? I’ve browsed the forum quite a bit, and could not find any reports, so I am tempted to do next PETG print without hairspray. Some say you should remove the print while the bed is still hot, but that’s difficult to ensure if it is a long running print which you leave unattended for longer periods. There are so many posts about PETG that I might have missed some - please point me to anything you know about. Thanks!
So far I haven’t had any issues either. Haven’t done very large PETG prints yet, but everything just worked out. Most of them just popped of the bed. And/or just flexing the sheet and they came off easily.
I always use glue stick with PETG.
Do I always need it? Probably not. But it just gives me an extra margin of error.
It’s especially helpful with items that are thin and flat (3mm or so) and I don’t want to have to bend them too much.
i pretty much exclusively use magigoo now, especially since i am printing on glass. the petg can rip the glass up i hear.
so i have been printing very well the past few days with petg, and a spool that i was convinced was bad, by changing my nozzle and then i calibrated with a .06mm shim instead and my flow rate is about 90ish, but the line width test says i should be even lower than that.
its a funky balance ive struck here, i get a little accumulation on the nozzle over time, but it usually doesnt interfere with anything, my smoosh looks amazing on the print sheet.
right now i am trying to set up again with more z offset at the same flow rate, but i anticipate it to have some gapping between the lines on my skirts which is usually what happens unless i am very close.
i might just stick with the method i have above, but i was hoping i could lessen the accumulation of gunk on the nozzle in the event it interferes with something.
maybe i should try to lessen my flow rate further instead, per the recommendation. i was printing at like 83 on PLA but i was told that doesn’t sound right.
Interesting. I’ve definitely had better results preheating.
I think it’s all dependent on if and how your bed is warped.
Mine is about as close to flat as one could expect.
It seems like with everything on the SM, your results may vary.
Try both and go with what works best for you.