- If you made this thing and are happy with it I kindly ask to give it a shout!
- Some thoughts about noise reduction at the end of this text.
- Update Jun.21st A version with supports added for those whose slicer does not
provide manual supports.
After several designs and although my prints got better with every one I was not entirely satisfied.
This one is designed to blow as near to the nozzle as possible.
There is one additional nozzle in the middle to cool down the heatbar and heat sinks.
Benchy and that little fu***r Marvin may speak for themselves.
What you need is, some M3 screws and nuts and two fans like the ones in the picture.
Of the fans I think they are quite common ones. And you can get them for just a few bucks.
Disassembling mine got a bit hairy (1st one destroyed). It turned out I had to cut the fans base exactly outside of the sticker using a sharp knife. I actually lost some hydraulics...
I recommend to use styrofoam glue to attach them for this glue does not solve PLA and altough it is quite strong it even can be disassembled. One has to fiddle a bit assambling the fans into their recess to have them running without touching the walls.
At the bracket one might have to rework at the chamfered edges but it is intended to sit somewhat tight, one would even have to press a little bit on top to get the screw in.
Print the base with some supports for the big bridge at the front. A small one could be of help at the base of the middle nozzle and could stay in place.
Use some aluminium foil and fold it several times and fix it with some glue to the bars on top of the nozzles. Fold the excess back as shown in the pictures. This proved to be pretty good a heat shield. My duct has been working for hours pretty well without showing any hint of melting at the nozzles. Parts from http://www.thingiverse.com/thing:1905135 will even fit for this one.
Having made this thing again for some reasons it had serious howling/noise problems
which bought me a well pissed off wife. To be honest it was that piercing and loud I have been pissed of pretty well myself.
1st thing is to take care that the fans are correctly positioned.
Facing each fan from the front they should be positioned as far as possible to the
upper right with the base in the recess. The nearer to the edge at the middle of the
base the louder. Some sanding of that edge and the fans base could be of help.
I learned that not all of those fans do have exactly the same rpm. Depending on that
with nearly the same rpm can lead to that piercing howl.....
That could be met with adding some small thingamajigs as shown in the last orange picture. For me parts of a toothpick did the trick. They cause some turbulence and
disturb the resonance. I certainly thought about adding that directly to the file. But
considering it not neccessary for everyone and those thingamajigs being way to small
to print I finally decided not to. It now is way more quiet with no noticable lack in flow.