Anyone try this with a 40x20mm fan? I have one from my old jigsaw setup. Moving to the MKIV and I need a 40x20mm mount.

Here is the version that ToM_Korn has on thingiverse.
http://www.thingiverse.com/thing:70748

I also included the sketchup file for the one I altered to fit my setup. My hotend right now is the printrbot hotend which is much longer so I had to put a pretty good extension on mount. Also, this is the PEEK retainer mount http://www.thingiverse.com/thing:89216 from dteck. If you have sketch up you might just need to make the extruded portion of the mount flush again to make it fit you setup. Either way, I hope this helps.

All very impressive,
still the bit I want to know about is how on earth do you print four colours from a single extruder. The green arrow is just pointing to a miracle but no-one has noticed !?
Are you using tartan or rainbow filament :-)

Wouldn't that be fun!  Tricky camera angle there.  It'd be even more awesome if it was extruding wire bundles!

Bought to proper crimping tool for $17 dollars.

jumpin jehosaphat, that's a good deal
i might have to look into that for hobby-time fun
we use a couple different molex crimpers at work which cost $200 each 

The Stl seems to use a 30mm fan.
I guess I can wire it to the extruder heater.

Don't do that. Do a G search for "ian johnsons gcode fan". There is more to this mod than you may think.
You will have to hunt down parts and do some soldering. Do another G search for "mcm electronics". They seem to have all that is needed for this. This is why it would be nice to be able to order a kit.

I've finally got around to designing the new fan duct for the mk3 clip on system. A smaller 30mm fan is used to be more compact, but it's plenty powerful. Too powerful for my un-insulated hot end. Turning on the fan caused the temp to drop until the extrusion failed.

I've had to update my hot end to cope and now the fan works well.

Please note that the mount in the link is suitable for designing other accessories around so they easily clip into the mk3 extruder:

Files:

Fan duct and mount: http://www.thingiverse.com/thing:44161/

Mk3 Extruder: http://www.thingiverse.com/thing:40711

Instructions:

1. Print the mount and the duct. I have oriented the STLs to make them print without support. a 30x30x7mm fan is shown in the picture as needed for this duct.

2. Test fit the duct and mount together. They should press on without drama or glue.

3. Clip the pieces onto the mk3 and tweak the angle so that the duct will direct air just under the nozzle, not so much on it. Remove the piece carefully and without moving them.

4. Permanently bond them together at that angle with acetone or glue.

5. Slide in the fan and clip in. Enjoy!

Very nice!

I use Lawsy's mount on the front of this, but I insert the attachments upside down since a 20 deep fan blocks access from the top.

This also functions as a bump plate to knock off prints so you can just chain each print's g-codes. Mass Production at it's finest!!!

If you DL and test it, remember to break away to thin wall parts blocking the idler arm from swinging in....and use sufficient perimeters so the walls are thick enough.