30mm to 40mm fan adapter
thingiverse
I was too cheap to buy a 40mm fan for my printer's Pi, when I had 30mm ones handy. I was also too lazy to redesign the Pi housing I downloaded. This is a sleeve that has mounting holes for a 40mm fan, but press fits a 30mm fan within it.
Download Model from thingiverse
With this file you will be able to print 30mm to 40mm fan adapter with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on 30mm to 40mm fan adapter.