u/AheyJay

Im having an odd issue ive never seen before. I am printing with Elegoo Rapid PETG at 245 deg nozzle and 75 deg bed. Im printing with PLA supports which continue printing just fine. When the print is running the PETG just kind of stops. In the 2nd Pic you can see my filament after unloading it.

This is the 2nd time it has happened, and only seems to occure on multi material prints. Last time the system recovered by just Unloading, trimming, and reloading the filament. So I dont think this is just a clog.

I am currently starting a single material print to see if I can isolate this to multi-material.

It feels to me like when performing the tool change retraction the filament the warm filament is stretching and the extruder looses grip. Does that make sense or should I be looking elsewhere?

Does that make sense or is there something else I should look at?

Edit to answer comment questions:

Spool was not stuck/tangled.

I do not own a filament dryer so this filament is "as shipped". This print was the same day the package was unsealed.

I was wondering if anyone had any experience with pillowing on the tops of their prints.

Using Elegoo matte PLA and the SnOrca Generic PLA profile. On the snapmaker U1

Its only happening at the edge of larger flat prints. Most recently it appeared near the door. Im not sure about the other times as my wife emptied the printer.