Fan duct for ZoneStar P802Q with J-Head hotend

thingiverse

I have a Zonestar P802Q, fitted with chinese J-Head hotend. I had problems printing PLA, after a few hours it jammed always.. No problems with ABS, though! But I figured PLA problem must be because of inadequate cooling, because the whole heat sink part was filled with melted PLA. I found here one air duct made by widddo, but it was for the stock hotend. J-Head has slightly larger heat sink: 25mm diameter and 50mm length. Especially the length is a problem, the 40mm fan is mounted flush with the top of the heat sink, so lower 10mm of heat sink is not really cooled at all. And that is the hottest part that would benefit most from the cooling. This air duct has a guide to direct at least some air to the lower part as well. This is not really a remix of widddo's work, as I did not use the original source code. But I did print his part before I realized it would not work. :) I used it as a reference for some measurements. Installation: Remove the cooling fan and the hotend fan. Hotend fan has M3 nuts, take them out and install to air duct. Lower nut is a bit difficult to install from inside of the part. Use M3 screw to initially tighten the nuts in place, so they will be at exactly correct position. Remove the teflon tube screw, and clip the hotend heat sink to the air duct. Then loosely tighten the fan screws so the part is roughly in right position. Reinstall the teflon tube screw. It might be difficult because the hole might not align perfectly, that's why the fan screws must be loose at this point. Finally tighten the fan screws and reinstall cooling fan as well. Print Settings Printer Brand: RepRap Printer: Zonestar P802Q (Prusa i3) Rafts: No Supports: No Resolution: 0.2mm Infill: 15% Notes: I printed with black ABS. Shouldn't be too picky about the settings.