I just wanted to document this little project because it seems like the different parts are all over the place and it looks like a pretty compact and lightweight extruder.
It's based on the PG35L stepper motor which is a pretty cool unit combining both the motor and a gear reduction in one package. I got mine, as well as the drive gear here: http://www.ultibots.com/ It was about $30 for both. Pretty expensive when compared to a Wades extruder with a NEMA 17 motor and hobbed bolt but I originally picked it up in order to get rid of the bowden-tube arrangement on my Rostock.
This is it near a 9V battery to show the size:
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The files that I used are all over Thingiverse.
The main body is here: http://www.thingiverse.com/thing:43457
It's a little different from the other versions because it doesn't have the integrated J-Head mount. I didn't like the integrated mount because it would have to be printed in ABS or else it could melt the extruder rendering the entire extruder useless. This version also has 2 bearings supporting the drive gear taking some stress off the motor and gearbox bearings.
The idler is here: http://www.thingiverse.com/thing:39098
Its under download: micro_extruder_idler_v2.stl
The other part is a cam-follower which looks like it may help with keeping tension on the filament and could make filament changes easier. It's here: http://www.thingiverse.com/thing:46618
This is the fan housing here: http://www.thingiverse.com/thing:52110
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I have read that these motors can be difficult with POLOLU drivers and can also overheat so I figured the fan would be a good idea. I'm awaiting screws and bearings in the mail so I'll report back when they arrive!
This is also an interesting use of the PG35L motors with a dual extruder: http://www.thingiverse.com/thing:24219
I just thought I would share this because the files are in a bunch of places on Thingiverse and I figured I'd put them in one place in case anyone is interested.
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