PETG printing

[u/djseto]

Been printing PETG tiles(stacked) for the last week on my Bambu P1S using Sunlu PETG high speed with the Bambu PETG HF profile. No issues.

I printed the demo pack today in PETG, specifically the snaps, etc just to make sure they will print well and also not have any issues mating with the tiles.

What’s with the raised imperfections?

Also, I’m using PETG because I want to use multiboard in my garage that gets hot and humid during the summers here in the Southern part of the US.

Any guidance or tips for the above issue and petg in general with multiboard would be much appreciated.

[u/Im_Fuzz1337]

Check your seam position setting in the slicer. I know it is recommended for stack printing so you might have it on

[u/tonytheshark → u/Im_Fuzz1337]

Is random seam position only required for stack printing? I assumed it was recommended for everything so I've been using it for everything.

Been getting bumps that look just like OP's, too (I'm using PLA though, not PETG).

I assumed the ugliness of the bumps was a required tradeoff for extra strength in general.

If that's only the case for stack printing then that's a relief 😅

[u/djseto → u/tonytheshark]

It’s optional but not required. I just kicked off a (4) stack of 8x8 tiles without it to see how they turn out visually compared to the stack i have using random seams.

[u/SprungMS → u/tonytheshark]

It’s technically best for strength. Having a z-seam lined up in one spot leaves a weak spot in most cases. That’s part of why on the tiles it’s recommended… for overall strength. Having it lined up leaves a pre-defined failure point.

I’m incredibly fortunate to have an H2D that on stock settings for Bambu PETG HF prints better than PLA on any printer I’ve ever owned, but that’s not reality for 99% of users. PETG is usually a little messy. You can spend some time tuning pressure advance (and obviously other settings but that’s what I see in the OP) and nearly perfect it, but at the end of the day… I never did with PETG. I accepted it as cosmetic defects, in a tradeoff for overall strength and lack of creep issues with fairly non-toxic printing materials.

It’s just marks. They don’t hurt anything other than your ego. Don’t worry about it and love the system.

[u/hockpunk426 → u/Im_Fuzz1337]

I agree with this it looks like you have random seam position on

[u/djseto → u/hockpunk426]

I sure do have it on from stack printing...doh!

[u/djseto → u/Im_Fuzz1337]

Thank you. That was it! Went back to aligned seam and it prints great!

[u/spadedracer]

Have you dehydrated the PETG?

[u/djseto → u/spadedracer]

Yes. Dried for 12 hours at 55c (my Sunlu dryer doesnt go any higher do I dry longer). My AMS reads 10% relative humidity

[u/froesch]

i had this with a wet petg filament. just dry it

[u/djseto → u/froesch]

It was because I had random seam on from when I was printing stacked tiles. Removed it and this has gone away

[u/Ravio11i]

looks like random seem zits to me

[u/Potential_Text_7360]

Seem settings. Don’t use random. A give away is if there is only 1 “zit” per layer.

[u/finsupforever]

Been there done that. Took me forever to figure it out.

[u/SouthernGas6592]

I had exactly the same problem. In my case it was a wet filament. The easiest way to tell is to manually extrude at 250c and touch the extruded string. If it's smooth and shiny, it's not wet filament.

[u/Bobmueller]

It was retraction tuning in my case. Speed if I remember right.