Prusa I3 Fan Duct for Aurora A3 Printer

thingiverse

UPDATE: This nozzle/duct thingy failed to improve my prints as I had hoped. I have designed a new Fan Duct for the Aurora A3 printer which does work as desired: http://www.thingiverse.com/thing:1351186 This is a remix of the "Prusa I3 Fan Duct with Adjustable Length" by Totosse, specifically for the JG Aurora A3 Prusa I3 printer. Perhaps if you have this exact printer, you may find this remix useful. The original Thingi had multiple problems: holes in the meshes, overlapping sides, internal facing borders and surface borders. As a result, it would not slice with Cura or Craftware. But it was the only design, out of 13 I examined and 3 that I printed, that came close enough to modify to my printer. I fixed all of the major issues and many of the minor ones so that it will now slice and print. I also extended the ring out 5mm so the print nozzle was exactly centered and increased the wall thickness in one area that was so thin that it printed as a single layer and so let air out in the wrong spot. Seven prints later, and I finally have a perfect circular fan duct for my printer! Why did I do this? See the last photo above. On significant overhangs without supports (I hate supports) I would get a lot of blobs. While printing, I noticed that these blobs only appear opposite the extruder head fan nozzle. The PLA would be printed, but would not cool off quickly because the air could not get to it (blocked by the print head) and so would curl up. On the next layer, that curl would get pushed out by the print head, thus forming the blob. Overhangs on the fan nozzle size would cool off quickly and solidify and therefor not have a chance to curl up. So, I'm hoping that a circular fan duct will evenly cool the PLA all around and rid myself of these ugly overhang blobs. Printer Settings Printer Brand: RepRap Printer: JG Aurora A3 Prusa I3 Rafts: No Supports: No Resolution: .2mm Infill: 15% Notes: Easy to print. No supports, rafts or brims. Prints in about an hour at 50mm/s