Update 30/5/18
Modified the support air output side to fit a conduit to channel the air to the printing zone and added conduit files. The conduit has a lid to channel the air to the printing area or to let it flow out of the side. The bottom side of the channeler is very simple and can be replaced with something you may like to design. The conduit and pther parts are better glued together to the main support.

Update 27/05/18
Added a knob for extruder motor shaft to help load and unload filament...of course, to turn it, the motor should be turned off. The knob fits 5mm shafts.
Added a little plate with embedded M3 nuts to make it easier to fit the belt lock plate.When printing, remember to pause to insert the nuts before the topside is closed.

As I updated a bit my Geeetech printer, I tryed to gain some printing area on the X axis but that is not that easy because of the printer's structure limits. I replaced the original extruder support with a PLA one, cutting down just few millimeters, and ended up gaining about 15mm.
By the way, that took me one step further and so I tryed to turn my direct drive extruder into a bowden setup. I didn't know if the support for the hotend would resist the heating during printing so I thought to add some washers on the filament tube with heat conductive grease, and designed the cooling case with a mount for a 30x30mm fan.
It works pretty well, I did a few 8 hours prints at 215° and even if the heatblock sits just a couple of mm under it, the cooling fan do a great job and it doesn't melt the PLA.
It is possible that at higher temperatures this little fan will not be enough so I will soon upgrade to a 40x40 fan.

The washers and part of the tube that sticks out at the top are cool and I discovered that bowden setup works very well, the X carriage is very light and I can get good prints at the maximum speed the machine can melt filament.
I kept the original belt clamp and that is the only thing that is a bit fiddly to fit as the nuts are in the space between the bearings plate and the fan mount and there is just the space for long nose pliers to get in to hold the nuts.
This setup made me gain 15mm extra on the Z axis mounting the hotend as high as possible on the bearing plate.
The part for the extruder motor fits on the original Geeetech gears, just remove the fan and heatsink and assemble the new part that has holes to fix it where you prefer on the printer, and the exit of the filament can take an M5 air hose quick fitting that screws directly into the plastic.

In the files there are the bearings plate, the plate to fit on the original extruder motor, the fan and hotend support, and the rendering of my cooling washers setup.

In the pictures is the first version of the fan support that had a little different shape...
There is another version in my files of the support with fitting for 40x40mm cooling fan that fits the same plates and accessories.

mini heatsink
Mini heatsink

extruder heatsink mk10
Heatsink MK10

heatsink washer
Heatsink washer

extruder throat mk8
Extruder throat MK8

4mm teflon tube connector
Teflon tube connector 4mm

30mm fan
30x30 cooling fan

40mm fan
40x40 cooling fan

GT2 belt
GT2 belt

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