Trying to perfect bridging with TPU

[FraggleRock 5]

I've been trying for a day or so to perfect the bridging profile for a TPU filament.

I'm using a model from thingiverse (I've attached it)

Unfortunately for some reason the filament behaves very differently for a narrow band of the bridging, and I don't know why.

Here are some of the settings I used:

Main extrusion temp 215c

No heated plate

No retraction

Bridge Skin speed 5

Bridge skin flow 60

Bridge skin density 100%

Bridge fan speed 100%

 

Any idea what may be causing this?

bridging_bench.stl