RepRap Universal Mini Extruder
Description
It features:
1. 1.75 mm filament
2. Adaptable mounting plate to attach it to virtually any 3D printer
3. Very compact high-torque NEMA 11 motor
4. Active ducted fan cooling for high reliability
5. Wade-style hobbed bolt filament transport
6. Wing-nut drive to spread the torque loading on the plastic gears
7. Push-fit hot-end parts - no thread cutting
8. Easily replaced PTFE liner for the hot end
9. A single M3-threaded rod cut to lengths makes all the fixings
10. Lightweight: 420g
11. Compact design (110 mm x 90 mm x 80 mm)
I based this design (loosely) on Jstkatz's extruder (http://www.thingiverse.com/thing:7037), in particular, the idea of using a lever to trap the filament against its drive.
Instructions
You must be logged in to post a comment.
the motor plate that fixes the nema11 to the assembly doesnt seem to have a fan clip?
Ooops! Sorry - should have read your actual question...
The motor plate does have a fan clip, but it's printed separately. You then glue it on. This is to make printing easier - no overhangs.
No - the Mendel version has a fan support. For Huxley there is a spacer that goes under two screws that attach bearings underneath; the spacer lifts the screw heads up to support the fan. In both cases the fan is clipped either side, but just held up underneath.
Im thinking that this could be adapted to become a Bowden cabled extruder for the huxleys, as it seems a shame to add a (small) lump on the axis.
Im currently printing one and seeing if this will be suitable, so will add the derrivitave after :)
The air flows first over the pinch between the small bearing and the bolt. All pinch extruders work a lot more reliably if the pinch point is kept as cold as possible. Even slight warming will soften some plastics a bit, and then the drive starts to abrade the filament, rather than driving it.
Next the air is ducted past the motor. This is just a courtesy call really - it doesn't touch enough of the motor to cool it a lot, and the motor runs quite cool anyway.
Finally the duct folds back on itself to cool the tops of the M3 threaded rods where they enter the drive and the top of the P
EEK insulator down which the filament runs.
The air exhausts horizontally just under the fan, going in the opposite direction to the way the fan is blowing.
I've been looking at this and at the reprap site, but I can't quite figure out where the ducted air goes. Is it just cooling the motor, or does it also blow down on the parts as they are extruded like http://www.thingiverse.com/thi... ?
I've been following the updating of this on the wiki page. Can't wait to build one!
License
More from adrian-bowyer
Awesome Extruder!
I was thinking of adding this to a hobby mill, not sure how with "Mach-3" and I don't use "EMC" yet, but I found something interesting about the "ModBUS" and "Arduino" Here: http://www.buildlog.net/blog/2...
Maybe there is a way to have Arduino work as the Extruder Axis controller using ModBUS?
Also what Nozzle are you using in the image?
I'll post findings when I take on this project, I have plans to start later this week.
There are several free RepRap packages that would allow you to control your mill plus an extruder from an Arduino. See here:
http://www.reprap.org/wiki/Lis...
Best wishes
Adrian