myplacedk

but it does not explain the weird burn mark of my initial failed print.

I guessing that when it was falling over, part it got taller. (Think of a 199 cm tall cabinet in a 200 cm room. It can’t fall over, it will hit the ceiling.)

As it got taller, the nozzle could dig in.

As the nozzle got embedded in the plastic, the heat would melt some plastic, and the dirt would stock to the warm molten sticky platic.

Yes to both.