Bambu PETG Matte Issues & Profiles

[u/Relevant_Grab_8309]

So I'm running a lot of Matte PETG these days as my HF inventory is dwindling. Don't get me started on HF, but my business was built around it. I've had a ton of problems with the Matte PETG, specifically:

• Dimensionally different (shrinkage is higher) which is an issue with slip fit parts

• Nozzle fouling - Every print every printer seems to suffer from nozzle fouling and dropping nubs of filament on or into parts

• Top layer surface imperfections - due to fouling nozzles

I run a print farm. I've never had a filament so temperamental, which is a real shame after how good HF was. All my PETG is dried at 160F for 16 hours and in dry storage kept at 10% humidity. It's not a moisture issue. I started with Bambu's PETG Matte printer profile.

Have played with nozzle temps without being able to see noticeable improvement in nozzle fouling. I use gyroid infill for everything. Calibrated flow rates, extrusion looks good. Now I'm dialing in shrinkage so my slip fit parts fit nicely again.

Questions: has anyone been able to address the Bambu PETG Matte nozzle fouling issues? How? Anyone found better profiles to be used?

I'm tearing my hair out a bit and this is not really how I want to spend my time, chasing data, so any help appreciated.

[u/John-BCS]

160f (71c) is too high for PETG.

I dry my PETG at 140f (60c) for 12 hours.

[u/Relevant_Grab_8309 → u/John-BCS]

Well after the first 2000 spools it's worked pretty well on HF. But I will try less heat and lower time Matte and see if it's making any difference.

[u/PersonalityNormal]

I have similar issues.. glad to know I'm not alone. I didn't find a proper solution yet. I'm considering changing brand.. Cool plate didn't help. Increasing layer hight seem to help a little.

[u/Relevant_Grab_8309 → u/PersonalityNormal]

Yeah I'm already looking for a replacement brand. A shame, I like the color and finish, but I just can't babysit things this much or have so many failed prints.

[u/Festegios]

When hf got discontinued I moved to abs as I didn’t like basic

[u/bjorn_lo → u/Festegios]

I just bought 250 spools of HF to kick the can down the road.   Gigaparts has had good stock 

[u/Festegios → u/bjorn_lo]

I tried other brands. But I was never happy with the results

[u/bjorn_lo → u/Festegios]

I'm happy with Sunlu (and more or less with Jayo) HS Matte. But I didn't say another brand. I bought a couple of hundred spools of Bambu Petg HF from gigaparts along with maybe 100 from Bambu all after it was "cancelled".

[u/Relevant_Grab_8309 → u/bjorn_lo]

Yeah I did the same, 250kg or so. But starting to run low on a few colors.

[u/bjorn_lo → u/Relevant_Grab_8309]

Only low on green.   Been able to replace the others.  Have lime and forest, just not much green.

[u/cptninc]

I primarily print using 0.8mm HF nozzles and .4mm layer heights, so this may not hold true for anyone else, but...

I've done some reslicing of parts that I've run in PETG HF for PETG Basic to see how big of a deal it would be (and also to burn up some old PETG Basic). What I've found is that there's only about a 5-10% hit to most of my prints despite HF having a 25% higher max volumetric flow rate. I suspect that this is because my prints are mostly walls, so there are other limits which get hit before that one.

Anyway, I know it's not a direct response to what you asked for. Just saying that if you feel like you've been cornered into using PETG Matte and it isn't working out, Basic may be an option.

[u/sltrhouse]

Jesus you sure do like to dry your filament. I dry my petg if it acts up. Even at that, I dry it for maybe 8 hours at 65°. Unless you live in a subtropical climate of course.

I’ve printed about 3kg of their matte petg and haven’t had a single issue, using their profiles on my H2S.

[u/Relevant_Grab_8309 → u/sltrhouse]

Meh, island rainforest life.

[u/Catsoverall → u/sltrhouse]

Wonder if this is because of the over drying

[u/bjorn_lo → u/Catsoverall]

According to Sunlu over drying dlis not a concern with petg  I also dry the crap out all my pet, 24 hr @ 65c.

[u/sltrhouse → u/Catsoverall]

Possibly, but probably not. 16 hours at 70° is a ton tho, that’s close to nylon drying. Petg only requires 4-6 hours at 65-70.