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Nozzle cooler regulated system for i3 Prusa/MK8 extruder (V3)

by Saur0n Oct 5, 2016
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In the second last picture, there is a black support attached to the extruder. Did you design it yourself? In the standard MK8 extruder there are just a couple of screw holes on the front side

I'm not exactly sure what are you asking for, but I guess you are referring to U shape motor holder. This is how it looks like in my case from the back of the extruder.

How many screws does it need? There are 4 holes (2 holes per piece) and they are coincident just in 1 position.. So there are different screws (4) one for each hole, right?

There are two screws to fix base to extruder, another two to screw the blower and one screw with nut - to secure height/relative position of both parts.

All of them M3? or M2? I have some issues with the screw M3 with screw. It doesnt fit.

As I wrote in description - all M3, can't double check it now because printer is working :) But it's plastic, just make a hole a bit bigger with drill or even scissors - size of the hole may vary on every printer, depending on how it's calibrated (if size on project is the printed size), every slicer may also do some modification and finally, some nozzle sizes rounds up/down small perimeters.

I've added the picture with all components and screws disassembled (since I had to replace bearing today in my printer) - how it helps :)


I reprinted the piece, not good even though my printer is calibrated.
someone else has managed


You can increase the tolerance between the two pieces? I can not assemble together

Have you tried use sandpaper? In my case it was usually a really tight fit, but if there was any print error sandpaper was a "must use".


I tried it with sandpaper, but there is a lot of work and the results are bad

Do you think that additional 0,25mm space on every slider and locking mechanism will do the work for you?


you can try increasing the tolerances of 0.25 mm?

I've uploaded the file with additional 0,25mm space on rails and side lock. It's enough to print just top part (only this one has been changed).

Have you seen any difference in print quality compared to the default white blower duct?

With default, which cools only in front - from one side, certainly yes. It's easy to check, just print test cube (like 20mm hollow cube) and you will see that straight edges on back will be blunt, but those in front (where fan blows) will be sharp.

I've also tried ducts, that are all around nozzle (like http://www.thingiverse.com/thing:714939), but I have seen no difference in print quality, comparing to one blowing only on two sides (like mine). But those going "all around", makes nozzle cleaning and print checking much harder and complicate.

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