Air Funnel Prusa I3 mk3 by Viczena

Last crawled date: 3 years ago

24/7/18
I CANNOT RECOMMEND THIS BUILD ANY LONGER!
I got a message from Prusa and they tested the design:
"Noctua fans dont like turns or long path to extruder. The distance to heat-sink is INCREDIBLY crucial. One or two mm forward/back is showing a negative impact. We tried something similar to this last month. I tested your design today and temperature was far worse than stock mk3 and mk2. I don't recommend your manifold. Stick with R3 extruder cover."
I also disassembled the fan-covers. Leave the fans as they are, the extruder needs any bit of air it can get.
I had the idea for this funnel from https://www.thingiverse.com/thing:2076234. It is used to reposition the small Noctua fan so it will not suck in the hot air from the bed, but from the air above. This helps the extruder to keep cool.
The original design was not compatible for the mk3, so I designed a complete new part. I included a tube for the fan wire. The funnel was designed as light as possible with stronger sections where needed. It can be printed without support.
Install it with or without the Noctua fan covers from the original posts.
For installation you need the following screws:
4 M3x12 for the fan without cover
4 M3x18 for the fan WITH cover
2 M3x12 and 2 M3x8 for the body.
Screw in all Bolts to the manifold before installation to be shure that all holes/threads are clean. Then start with the two inner screws and handtight them. After that you screw in the outer screws, thighten them first and the inner screws last..
You have to open the cable bundle from the extruder to Einsy case to gain around 2cm more length for the fan cable.The cable will be held in position and covered from all moving parts by the inbuilt tube.
The funnel is fine to be printed in black PET, like the extruder body. The covers look good in neon orange with blackend screws.
UPDATE 11 22/7/18: Version11 is improved in that it has a clean inner air funnel, which helps to keep the air stream linear. I made this version for the Extruder R3 body update, which depends heavily on a non-disturbed airflow. Version11 elongates the input air travel distance and therefore helps to clean out turbulences. I had the same positive effect with motorcycle manifolds which were elongated as far as possible into the air filter system.
The cooler air which is sucked from above is another add-on.
The inner funnel increases the stability of the design without adding too much weight. Version10 weighted 11g, Version11 weighs 14g. It is still a lightweight design.
UPDATE 12 22/7/18: Version12 has a little more material on the cable tube for a nicer print without support.