I tried to reproduce my success with the benchy and had failures where the bridging for the roof happens. Filament is curling up at the corners of the "house" on the benchy and eventually there is a collision with the hot end that causes the print to unstick from the bed. A few things are going on: Cooling is not adequate for good bridging Cooling air seems to be hitting the hot end and possibly cooling it A re-design of the nozzle is required to address both. I'm going to change it so it fits around the opening of the fan and can be printed with the opening down on the bed. I also think that the 4010 fan doesn't blow evenly across its opening so the new design will narrow and provide asymmetric flow channels. But development is going to be slower now that I'm back from vacation.