I found myself replacing a couple of fan blades in tools and a hair dryer and got interested in making a parametric model to use for different products.

My goal was to make it easy to modify critical parameters to allow it to replace most fan blades and make it fully printable without support.

The coolest parameter is the blade count, but you will need to go back in to some of the extrusion and rotation features and either add or remove objects under “Objects to Cut”. You can even upgrade your repair with more blades.

See the included images for a list of all modifiable parameters.

Open the .f3d file in Fusion360 and go to Modify > Change Parameters. 

Blade curve parameters must be greater than 0, so I set them to 0.1 if I don't want any curve. Rake determines the forward or backward angle of the bottom or top of the blade from the hub. I would suggest setting this to no more than 30 degrees and no less than -30 degrees. The shaft dimension should be approximately 0.2mm less than the actual metal shaft of the motor for a snug and secure fit.

Finally, combine the blades and hub and you can add any fillets or chamfers to make a really great looking final replacement part. Mirror the final part in Fusion360 or in your slicer to change the rotation direction. Export your file as a .3MF for a precise geometry and you're ready to slice!

I print these at 0.1 or 0.12 layer height in ABS with enough walls to fill the entire model and no support and they have worked wonderfully.