PETG do you need a Enclosure?

I am printing using my Mini some eSun PETG filament. Its coming out nice, but I had a failure about 1/2 way through my last print yesterday and did not have time to analyze. I have been using 245/100C .5 mm nozzle and a enclosure.

I was wondering since I was just using the profile for ABS in Simplify 3D I needed to change anything?

All of the rest I have done with PETG except for the last one have turned out beautifully. I am also wondering how it compares with ABS for strength?

Well I am doing another print right now, same settings as before but without a enclosure. My failure to print yesterday was due to a jam in the roll feeding. Corrected and cleaned out c r a p from the hobbed bolt and blew out the whole works with low pressure air. Its printing now… so time will tell. I love this little Mini, having second thoughts on selling after getting the TAZ 5.

No enclosure and room temperature about 75 DegF and it came out perfect.

Did you use the ABS print settings from lulzbot for this PETG filament?

Thanks

Yes , and it works fine. It’s a little more flexible than ABS and I am using eSun brand purchased on Amazon or eBay. Great stuff.

Has anybody found a way to get PETG Not to adhere to the PEI table so well? I have the table set to 90 during the print, but afterwards it is a royal pain to get off the table. I used PET tape and that was even worse.

I really like the strength of PETG and that it doesn’t shrink or warp, but I don’t want to break my table removing the prints.

Could try a Z-Offset Gcode… set in .2-.3 in slicer software to see if it helps.

Thanks, I will give that a try. I use the stock ABS settings (except I lower the bed temp to about 90). The filament is a bit thicker, so I set the filament diameter appropriately (2.97mm). However it still seems to over extrude. Changing the flow % didn’t seem to do anything.

Raising the z-axis did not help. It would either continue to stick or separate completely from the surface. The solution I finally found was to cover the platform with paper and then blue tape. The paper doesn’t stick to the platform and the blue tape separates easily from the model, but has enough adhesion that it prints ok. Either one by itself was a problem. I raise the z-axis accordingly. This technique works for large flat prints. For prints with a small surface area, separation from the platform isn’t such a problem.

I use a PVA gluestick as per Lulzbot recommendation. It makes it a little easier to remove once cooled. Oh, and don’t close your enclosure. I run mine with the enclosure open, and the enclosure fans on. This stuff does not like a warm environment to print in.

I think you need to vary the adhesion method depending on the print. My prints cover about 2/3 of the build plate. I almost broke the plate trying to get it off with PVA. You don’t need an enclosure, but it should not be too cold an environment or really large prints will warp even with PETG.

PETG likes to print hot. Even hotter than what appears to flow well. Mine flows at 230C but sticks hard to the PEI and doesn’t print super nice. At 245C it prints better and adheres a little easier to the PEI so its not quite so bad to get it off after it cools down.

After reading this thread I decided to try PETG – I got some eSun natural. I’m using a Mini and I didn’t have problems with adhesion to the buildplate at 85C, or with removal once cool. I did about 10 prints ranging from 1 to 17 hours each.

I did have a problem with fine stingy hairs – I basically had to shave my parts afterward. I tried printing with the hotend at 235, 240, and 248 and the fur was lessened at the higher temperature but still prevalent. At all temperatures, I got some burnt blobs of plastic stuck to the prints too. I turned the cooling fan up to 100% for the entire length of the prints.

I also had trouble with it making a mess of the nozzle – after just one print the nozzle would be seriously covered in goo that I had to clean by hand. After a few prints I just disabled the auto-wiping feature and manually retracted and cleaned the nozzle – the autowiping couldn’t deal with the amount of gummy residue left on the nozzle and I was getting bad reads during Z-height probing.

Anyway, I do like the flexibility of this plastic and not a single piece cracked or warped like I’d have with ABS – even overnight prints where the ambient temperature hit the low 40s (I’m printing in my unheated garage). I’m not in love with the look of PETG or its tactile qualities, but I’m having a lot more trouble with ABS now that it is getting cold, and I can accept what I don’t like in exchange for prints that work.

Any suggestions for fighting the hairiness? Burnt blobs? Do I just have to accept that this filament is more messy and requires more frequent manual cleaning, or is there a way around that?

I don’t know of a good way to fight the stringiness. I print at 250 and set the filament diameter to 3.1. It is better to underextrude PETG than overextrude. Having it underextrude reduces the number of blobs that it generates. I also do print-one-at-a-time as that at least reduces the strings exterior to the parts.

Do you have Retract checked in your software? I have mine set On and at 1.5 seems to get rid of the strings. But PETG likes to be warm, I question the use of the fan.

did you try changing retraction settings to 4mm and about 17mm/s that should help the blobbing… its likely caused by oozing during retraction if you are running the standard 1.7mm setting.

I did increase my retraction, but not by as much suggested here. I’ll give that a try.

My thought on the fan was that if it cooled the filament quickly, it would have less chance to make fur. I can’t recall now for certain, but I think I started at the normal ABS max of 60% and stringiness decreased when I bumped it up, but I’ll try with lower than ABS and compare the results.

I use 50 degree bed with gluestick without an enclosure and it prints perfectly. I used the Cura tGlasse filament setting and then switched to expert mode to control quality through layer height. Hope that helps.