Dual Part Cooling Fan Mount for BunnyScience BNBSX Short Ears MK3S Extruder

thingiverse

This is a remix of jonathanrswift's clever dual fan mount, but modified to mount on BunnyScience's BNBSX Short Ears MK3S Extruder. All credit goes to jonathanrswift for this highly effective shroud. I appreciate the simulation work that went into this shroud and to be able to see the nozzle is what I always wanted. April 18, 2020 Long-term use and findings I'm pleased to say that this shroud has been great for my printing. Overhang performance is pretty good. You can print fast, and now, there's a little light to help with first-layer quality assessment. I do have a couple notes you should consider in using a dual fan setup. Big tip: Try to use the stock fan, and make it a pair. I've used nice quality LDO fans, 5V/3A although their RPM is 5,000. To print with a slower fan speed is a problem, because Prusa's system is set up in the firmware to run its stock fan, which is 5V/3A, but with an RPM of 4,500. Why does this matter? Well, we have to understand that the fan has feedback, a yellow signal wire as a tachometer sensing how fast the fan is. If the Einsy/firmware expects to keep a fan at 30% but the reading from a faster fan is off, it is bound to error. I've printed a lot with the LDO fans, but mostly PLA and fast prints. If you wish to go slower with .1-.15 prints, this setup may not be compatible. If possible, make your two fans Prusa fans from the start. 02.23.20 - Version 2 (non-lighted) and 3 (Lighted) [*If you can't download the file(s), go to the 'Thing Files' tab and download from there] For these versions, I wanted to tweak the outlet nozzle on the right a little. Didn't seem like enough air was coming out as it should and I thought the aim was a skosh off. I did several tests, as evidenced by the multitude of shrouds I'd printed out and tested. This newer version should work better. It turns out, the version I used to modify to a BNBSX extruder was not directly from the original designer, as it was modified to fit a Bunny gear setup on an MK3S extruder with BLTouch (JojoStein), therefore it had previously been modified. I essentially modified the shroud to be closer to the original. Additionally, I restored the 'delta' style bracket as I liked the balanced appearance. I also extended the flange under the left fan to grasp/cup/support the fan's outlet a little more. On the right, I raised the flange for the same effect. (I actually broke this off in my pictures.) Supports are still indicated as bridge, blue, and that's fine. It will still support and slightly fuse, but should separate fairly easily. 11.19.19 - Version 1 The only modification, besides moving upper mounting points, closing/cleaning open geometry, is that I added a loop to which you can insert a zip tie, and secure the fan wires so that the wires clear the exhaust side of the heat sink. See pictures. I didn't like the 2nd fan wires drooping down, flubbing around in the hot air pushed out from the Sunon extruder fan, and possibly adding turbulence to the exhaust, so I thought it'd be nice to legit secure the wires to the bracket. I hope this helps you get started with your printing!