Airfoil data based snap-on fan grilles for AnyCubic Mega X

thingiverse

My new Anycubic Mega X came with an annoying sound as soon as the fans of the extruder unit switched on. The root of the problem is a design flaw. It took me 20 seconds to get rid of it. With a pair of pliers I pinched out the poorly designed grills - a couple of "singing" holes drilled into the sheet. In order to again protect the fans I designed a pair of snap-on grills that can be mounted without any disassembling. For proper aerodynamics I thought it might be a good idea to design a guide vane ring using proper airfoil data, radially twisting Naca 17413 to be precise. Guide vanes are capable to enhance the airflow by tweaking the angle of attack for the fan blades. I measured the design with a scaled up version and an 80mm fan and found an increase of air velocity of about 15% which indicates an increase of flow volume. The extruder cooler is an axial fan and has a larger diameter (35mm). I designed the grill with maximal diameter as it can be snapped to the screws. The outer diameter of 40mm is slightly oversized and should fit between the screws with a little squeezing. There is also a version with lugs. The parts cooler is a radial type and the sheet has there a 36mm opening. There are 6 slightly oversized snap-on extensions that also need a little squeeze when mounted. I didn't publish - and clean up ;-) - the OpenSCAD code as the STLs can easily be scaled.