Delamination of perimeters or under-extrusion with Arachne
Hi,
I was printing some hooks and noticed the perimeters where delaminated. At first I thought it was severe under-extrusion, but I hadn't seen this problems with other, larger models I printed recently. So on a whim I decided to try the classic perimeter generator.
The Arachne version is on the left, classic on the right. Obviously the problem is not there with the classic generator. The object is also, of course, much stronger.
Is this just an Arachne issue or is it just under extrusion?
The print was with PETG, 0.6mm nozzle, 0.2mm layer height. I set 6 perimeters to prevent any infill.
RE: Delamination of perimeters or under-extrusion with Arachne
Yep, it does that.
Already reported on the PS github. For example https://github.com/prusa3d/PrusaSlicer/issues/8578 or https://github.com/prusa3d/PrusaSlicer/issues/8605 or https://github.com/prusa3d/PrusaSlicer/issues/8561 , basically they don't think its a issue of the slicer as they keep closing issues related to it.
You can adjust settings to help with it or just use classic.
RE: Delamination of perimeters or under-extrusion with Arachne
There's plenty good with Arachne but alas also plenty wrong. I'm in the habit now of comparing both Arachne and Classic for everything I print. Too bad it came out, or more precisely, was made the default, without enough testing.
RE:
Thanks for the links to the Github issues. So the reason given for closing the issues is that they say that the issue is caused by under-extrusion which gets hidden by the different way extrusion works for the Arachne vs Classic generators. So, I went through the whole song and dance. I first did a e-steps calibration (I have a Bondtech extruder) but that was fine.
Then did a calibration cube and I did have too thin walls. I set the extrusion multiplier to 1.08 and reprinted the object using the Arachne generator. And low and behold:
So it looks like under-extrusion was the cause after all. The only thing I am wondering about is if a multiplier of 1.08 is not a tad high and might indicate another issue.
RE: Delamination of perimeters or under-extrusion with Arachne
There are several of us that think arachne isn’t ready for prime time. At least with the default settings. There have been too many others having issues. But they do like their shiny new toys.