Prusa MK4 Fan Shroud for better TPU/all other filament Cooling

I had some trouble mit the MK4 and TPU. On my older MK3S it works perfect, but with the MK4 I  have some stringing and temp, retract settings are not really solve the issue. For this I change the original fan shroud and add a new air outlet to the right side from the nozzle. With this new shroud I get much less stringing. 

Printed on the MK4 with in Prusa Prusament ASA Prusa Galaxy Black.

Testprint with “5” was with Original Shroud. “1” was printed with same settings, but with this New Fan Shroud. TPU was from Sainsmart.

Add stl without text (by T.R.)

Add FanShroud_ver2.stl with smaller tunnel and so more layer on top of the tunnel if someone print this in 0.15mm. Hint from @wedgeworks. 

Add ver3.stl with improved airflow and reduce material (v2: 9,23gr vs v3: 8,73gr, not so many :-) )

Reduce the tunnel size to print with 0.15mm LH.

Add ver3.stl with improved airflow and reduce material (v2: 9,23gr vs v3: 8,73gr, not so many :-) )