This time we are trying to improve the print fan duct to better control cooling of the prints on our Prusa i3 Rework. We are hoping to improve upon print performance on bridges and overhangs. If we can cool the exudate faster then it should stop our bridges collapsing slightly or those unsightly first layers of the bridge.
Oval shaped holes are a good indication. The idea is that if we can direct the flow of the air from our print fan better it will cause faster cooling. We have the print fan rigged to the D9 outlet of our ramps board so we are able to control speed from our 3D printer software (Repetier host) as well.
Version one fan duct design
It all seemed to go OK. We regard this as version one. We spent most of the time learning FreeCad ‘s “Loft” function where you can create to wire shapes in the Draft workbench and then connect them forming a solid using the Loft function on the Parts workbench, this is how we created the extra long nozzle to our fan duct.
The tricky part was hollowing out the solid shape we had created, we tried a number of options which we believed would work but the only one that in the end achieved this was to create two solid forms and cut the inner from the outer. What we did learn is that we need to take a more modular approach to part design. This is what we are going to try and incorporate into the design of version 2.