the internal cooling fan in my GMC jointer failed, so the jointer got really hotafter only a few joints. GMC no longer exist so i decided to make my own fan, though i had to guess at the form and measure the dimensions of the space, and the shaft/locating lugs. Came out ok, with a good press fit on the shaft though the first print was too tall and had to be reduced by 4 mm. My very first attempt to make from scratch, I'm a complete newby to 3d printing of any type. Used ASA for strength(?).