Hard to tell, most of it looks fairly good except a few spots here and there.
That could be grease on the print bed, maybe time to give it a wash?
When PETG goes wrong for me, it’s this 90% of the time.
I use hot water and a little detergent with a lot of rinsing.
Use gloves because even clean hands leave oils behind.
With PETG it’s hard to get the first layer right but if it’s good the rest of the print generally goes fine.
Molten PETG is very sticky and if you get a bit stuck to the nozzle it can build up, get worse and suddenly take out a bunch of nearby lines leading to gaps in the layer like this.
To counter this PETG first layer should be:
Printed very slow e.g. 20mm/s
At a higher Z offset than PLA, the plastic should flow out the nozzle and fall onto the bed rather than be squished flat.
High bed temperature 80C / 176F
Zero or very low fan speed for the first couple of layers
If you can see marks left by the nozzle it’s too low. The lines should have a rounded look.
It could also be wet filament, does it make popping sounds when printing?
Thanks, I washed the bed and dried the filament, and it printed fine for the most part. The nose lifted up a bit, may be I left some soap residue there, but other than that it printed fine.
I found alcohol (IPA) wasn’t a reliable fix for all failing 1st layer issues.
I still use it because it seems to slow down the inevitable and it’s quick compared with a trip to the sink.
In my experience you still want to use soap and rinse occasionally. Since you don’t typically rinse with alcohol you can just move the oils around. Also depends on what % you use.
Hard to tell, most of it looks fairly good except a few spots here and there.
That could be grease on the print bed, maybe time to give it a wash? When PETG goes wrong for me, it’s this 90% of the time.
I use hot water and a little detergent with a lot of rinsing. Use gloves because even clean hands leave oils behind.
With PETG it’s hard to get the first layer right but if it’s good the rest of the print generally goes fine.
Molten PETG is very sticky and if you get a bit stuck to the nozzle it can build up, get worse and suddenly take out a bunch of nearby lines leading to gaps in the layer like this.
To counter this PETG first layer should be:
If you can see marks left by the nozzle it’s too low. The lines should have a rounded look.
It could also be wet filament, does it make popping sounds when printing?
This would be my guess as well. Those spots where it isn’t sticking look like they might be where fingers have held the plate.
Thanks, I washed the bed and dried the filament, and it printed fine for the most part. The nose lifted up a bit, may be I left some soap residue there, but other than that it printed fine.
I just scrub it with rubbing alcohol, works great. Is that not good?
I found alcohol (IPA) wasn’t a reliable fix for all failing 1st layer issues. I still use it because it seems to slow down the inevitable and it’s quick compared with a trip to the sink.
In my experience you still want to use soap and rinse occasionally. Since you don’t typically rinse with alcohol you can just move the oils around. Also depends on what % you use.