This is a upgraded variant of RichRap's syringe style paste extruder. It substitutes a few easier to find bits of hardware to replace the longer M4 stuff I had a hard time finding. I also spent some time cleaning up odds and ends fitment wise(more work needs to be done!) but it works well and take less time to print.
It is based around a 10 ml/cc syringe. The best type is the Leur Lock ones with interchangable tips, but I've had good result with the measuring type syringe with the simple spout without needles.
BOM for Paste Extruder 10 cc V2.1
_1 x Print - Plastic Body V2.1 Extruder
_1 x Print - Gear and drive set (small gear, medium gear, large gear, idler block, syringe pressure block
_1 x NEMA17 motor, 5 mm shaft _1 x Drive gear T5 10teeth Metal drive Gear (you could print one of these)
_4 x 624 bearings _1 x 608 bearing _1 x 20mm 8 mm smooth rod or M8 rod _2 x M3 set screw for stepper drive gear & belt pulley
_4 x M3 nuts, tension, drive gear & pulley
_2 x M3 x 45mm bolts for idler tension _4 x M3 x 10mm bolts for stepper motor mounting
_7 x M3 washers _3 x M3 Nuts _3 x M4 x 30mm for idler hinge pin
_1 x M4 x 55mm hex head bolt for the large gear shaft
_1 x M4 x 45mm cap screw for the double/medium gear shaft _1 x M4 plain nut for syringe clamp _3 x M4 Nylock type nuts
_4 x M4 washers, between gears and 624 in cap
_2 x springs or Silicon pressure spacers for Idler
_1 x small zip tie
_1 x 5-6mm wide T5 belt(or to match pulley) ~about 40cm
_1 x Plastic sheet to print on
Standard 10ml Syringe - Luer Lock or centre slip types. Various syringe needles 1.8mm - 0.1mm - For Luer Lock syringe. Syringes with offset nozzles can also work, make sure to clamp in place so they don't rotate in use.
We build 3D printers!
I've been following the RepRap project since about 2008, and building 3D printers since 2011. We started with a Techzone Mendel, and then I used it to print the parts for a Prusa version 1 which morphed into a verison 2. I used that machine to print up a pile of Prusa i3 parts. The cycle just keeps going!