This is an extruder upgrade designed specifically for the Replicator 2X, but with improvements like it is now suitable for use with FLEXIBLE FILAMENTS!!!!
OK...01May14, We have used a highly modified Recreus Hot End kit (by chopping the Aluminum Heat sink fins, tapping the thermistor hole to fit a STD Makerbot one, and insulated it) and the REV4 Extruder works out-of -the-box, but not optimally. We will be releasing the REV 5 extruders, and a newly modified Fan Duct REV 2 with a modified cooling tube back to the extruders which has made a huge improvement in cooling the area around the filament in the extruder area before it feeds into the hot-end tube...
-base is fully printable without supports(REV4=DESIGN TWEAKS include enclosed guide tube to control flexible filaments like FILAFLEX, and NINJAFLEX)
-arm is printable with only external supports for bearing slot(REV4=slight geometry tweaks)
-arm integrates feed tube mount as well
-tension spring geometry improved
-use 5/32" and 1/4" bits for tight clearance bearing/arm pivot holes
-uses Makerbot hardware kit for Rep2 + 1 extruder screw ($8 ea from Makerbot.com)
-can be pre-assembled for quick swap (under 2 minutes each)
-L and R extruder parts included, and labelled (common pin)
from everything I have read, the Makerbot 2X can print the FILAFLEX filament, but it needs to have a guide tube into the hot-end feed tube. We have redesigned our extruder to have this, and give the filament nowhere to go except into the hot-end. Without the PTFE liner, feed speed must remain below 50mm/sec and temps between 205Â°C and 220Â°C...we have not confirmed this, but will very soon...just thought we would give the community something to start with
Again...feedback is greatly appreciated so we can continuously improve the design.
-Acquire the Rep2 extruder upgrade kit hardware only. ($8 ea shoudler bolt, small FH screw, bearing, spring) from Makerbot
-I printed it at 0.20mm layer with no support on base, and external supports for the arm just because of the bearing channel.
-you will need to chase the bore for the bearing shoulder bolt with a 5/32" drill bit just to make sure it is a tight fit.
-you may need to chase the 1/4" pivot hole in the arm to make sure it is a tight fit as well.
-you will need to lightly file the pin flats, and round edges to make it fit tight into the base key slot
-the base key slot has a relief at the bottom to make sure the pin seats flush and square with no radius in the corners
-included parts are LH-Arm, LH-Base, RH-Arm, RH-Base, and a common pin (print 2 of them, and one each of the others)
-put the small flathead screw into the deep corner countersunk hole in the base part.
-put the pin into the arm part so it is flush on the outside face
-put the bearing into the arm slot and secure with the shoulder bolt
-shoulder bolt head should be flush to the outside face, and the threads should stick out the back
-bearing should spin freely
-put arm onto base rotating the pin so the shoulder bolt threaded end rests in the curved slot in the base face.
- now that the movement is limited in the arm via the threaded end in the slot you can add the spring
-place the spring on the bottom perch and compress it into the arm perch.
-follow makerbot instructions on how to remove the existing extruder.
-place the newly pre-assembled extruder upgrade onto the stepper. You may have to compress the arm slightly to move the bearing out of the way of the drive gear.
-new extruder should seat flush to the stepper face.
-use one of the long flathead screws from the removed Makerbot extruder through the corner pin to secure the new 2X extruder upgrade to the stepper.
-tighten until snug, but arm moves freely with very slight resistance.
-press the arm down until you can insert the hex-key though the arm hole to tighten the small flathead screw in the other corner.
-repeat entire procedure for the extruder upgrade for the other side.
Please let know if you have any suggestions on improvements.