PrintrBot Plus 2.1 Dual Alu Extruder System

thingiverse

These parts provide the means to attach two PrintrBot Alu direct drive extruders to a PrintrBot Plus version 2.1 (1311). They may work on older printers, but not with the X-Z upgrade. I plan to add this to my printer in the future and then create an adapted version for the X-Z upgraded Plus. It has many fan mounting spots for cooling: 4 to cool the motor at the back, 4 to cool the aluminum extruder parts, 2 to cool the Ubis extruder, and 2 to cool the print job. Most of these are not needed but they're there if you want to use them. There are also slots for the M3 nuts for some fan mounts. This design can be easily modified to use a single 80 mm fan for the aluminum extruder parts and the motor but I've chosen to use smaller fans to keep the weight down. All the little raised slots around the edges are for zip-ties to keep cables tidy. I love this idea, as it's so useful for keeping things organized. When you attach these parts to your printer, be prepared to lose about 20 mm of X-axis movement due to their width. Make sure your max movement is set to 180 mm on the X axis. The extruder offset is 37 mm on the X-axis. This means it's 37 mm from the center of the left extruder (extruder 1) to the center of the right extruder (extruder 2). From the support wall along the Y-axis, the center of the extruders is 17.45 mm away. I call this the "support wall" because it's the vertical wall behind the extruders where you mount the linear bearing sleeves. For reference, the original wood-based extruder is centered at 15.76 mm and the single aluminum extruder designed by PrintrBot is centered at 17.4 mm from the same wall. You may need to slow down your printer due to the additional weight of the second extruder, motor, and hot end, which can cause shaking. I've managed to print at 75 mm/s without any issues, but you might want to take it easier on your printer. When printing parts for your printer, use ABS filament because PLA may not be able to handle the heat generated by the two extruders. Use at least 50% infill (I used 75%) and set your walls to 1 mm thick (I went with 1.2 mm). Bill of Materials: * 1x PrintrBot ExtrudrBoard * 2x Nema 17 Large Kysan Motors * 2x Aluminum Extruder (or equivalent) * 2x Ubis Hot Ends (metal versions work too, but I haven't tested them) * 0-8x 40 mm fans (at least 4 are recommended: 2 for the motor and 2 for the print job) * For structure: + 2x Press Fit Bearing Sleeve + 8x M4-10 Screws + 9x .5" 6-32 Screws + 9x 6-32 Nuts + 2x M3-12 Screws + 2x M3 Lock Nuts * For belt tension: + 2x Thumb Screws + 2x M3 Lock Nuts