Prusa XL Fan Duct Upgrade

Our upgraded fan duct for Prusa XL printers ensures optimal cooling performance, leading to smoother and more precise prints. Ideal for professionals who demand precision, this upgrade integrates seamlessly with your existing setup. This fan duct upgrade is a major improvement over the OEM part cooling fan duct and all currently available aftermarket versions on Printables and other model sites.
 
The root cause of the Prusa XL cooling issues is that the frame the cooling fan bolts to extends too close to the print bed. This forces the fan duct to either be single sided; which results in poor cooling performance when the print obstructs the airflow, or for multi sided ducts to be too narrow and therefore overly restrictive of air flow. To address this problem we made a fan duct with a venturi around the frame protrusion that expands to a much larger size both upstream and downstream of the restriction. This design also does a better job of directing the airflow at the nozzle than other designs and includes a variety of other improvements. This end result is much better cooling with a higher flow rate with a bidirectional flow arrangement.
 
This design was tested against the fan duct by Livius:
https://www.printables.com/model/622164-prusa-xl-fan-shroud
which was the best of the aftermarket XL fan ducts we have used to date.
 
This obstructed overhang test was used for a side-by-side performance comparison:
https://www.printables.com/model/342481-overhang-test-regular
In the default scale and then stretched in the X/Y axis by 100% (to make the overhangs even more extreme). In the test photos, the overhang test on the right-hand side (labeled 1) was printed with our fan duct, and the test on the left-hand side (labeled 2) was printed using the Livius duct. Both models were printed in PETG with default Prusa Slicer settings.
 
From personal experience, this fan duct outperforms every other type we have tried and does particularly well with round overhangs (which are tough to get good cooling on). These fan ducts are now the standard on our XL printer extruders.