I'm not sure there is a good fix for this, but here's the problem:
I use PETG a lot for it's strength and (relative) ease of printing. It's one annoying property is that it tends to stay soft & sticky for a while, so it strings like crazy without the right settings. On a couple recent models, I've discovered a new issue with vertical holes. The latest model has 5 perimeter passes. It prints the outside perimeters just fine on the first layer, because the model is large enough that each pass has time to cool before the extruder comes around again.
Before it fills in the bulk of the first layer, it prints the perimeter of the hole. The hole isn't overly large, so each pass doesn't have much time to cool before the extruder comes around again. Every time I try to print, one or more of the perimeter passes for the hole sticks to the extruder and gets ripped up off the build plate. I'm using a thin film of glue stick for adhesion, and it works great for the full model, but it can't keep the tiny half molten pieces of the hole perimeter stuck down against the forces of the next extruder pass.
Although the general advice for PETG is not to use cooling, I've found it essential for smaller models. However, if I use cooling for the first layer hole perimeter, I have to use it for the entire first layer, and I suspect that may cause adhesion issues for the overall model.
I don't know of any way to tell S3D to use cooling for just a specific section of a layer. I'm already using a 40% 1st layer speed, and a 50% outline underspeed. I could try to slow the outline underspeed down further, but I'm not sure if that applies to only the 1st outline pass, or to all the perimeter passes. I think it's just the outer/inner most perimeter pass, which won't help.
Any tricks of ideas on how to lick this problem?