The GT2 belt I ordered is on back order so I guess the Extruder head will be done before the anti-sag truss. I have chosen a different extruder head than I originally planned.
I am using Laird’s V11 extruder instead of the one from Proto-Plastik. I like that it cools the print head in addition to cooling the extrudate. In addition, it is about 10mm narrower than the factory one so I will get back some of my print width.
Printing the Extruder Head
Laird provides a single model for the entire V11 upgrade, but it is larger than my printers max x-index and y-index, so I printed the parts individually. I continue to rotate each part so the long axis is on the y-axis instead of the x-axis because of my limited usable width due to x-gantry sag.
It took about 8-1/2 hours to complete, but the parts look pretty good.
I am ready to start building the extruder head. I wonder if I will be able to click the existing LM8LUU bearings into the one-piece mount plate I printed out, or if I will have to disassemble the X-Gantry… again.
Removing and disassembling the factory extruder head
CAUTION: Before removing the extruder head; heat the head, retract the filament and let it cool back down. You don’t want a 190°C extruder head lying loose on your desk *ahem*. Removing the extruder head turned out to be very straight forward. I simply removed the four M3-30mm and four M3-25mm screws holding the LM8LUU bearing mounts to the extruder head. Be careful as you remove it, remember that it is super glued to your x-belt and if that comes loose the head will swing around. Also, in case it doesn’t come loose (mine didn’t), be careful removing it from the belt, the super glue may have weakened or stiffened the belt and you don’t want to damage the belt.
After the extruder head is removed from the printer, remove the extruder tensioner screw, then just proceed to remove any other screws as you see them, order doesn’t seem important. During this step I noted two separate wooden parts that were cracked, one was broken completely through.
1 x 1038-2RS Bearing
3 x M3-45mm screws (you really need four, but the TwoUp only uses 3)
1 x Nema-17 Extruder Stepper Motor
1 x Hot End
Use the 1038-2RS bearing and what appears to be a couple of thin film washers. I don’t remember putting them in, so I am guessing they are actually a seal that was on the bearing, but they are slick and the small acrylic washers are thick enough to bind the bearing.
Put the Nema-17 extruder stepper motor down on the table top, then put the front half of the extruder body on top, with the filament tensioner lever on top. Partially screw an M3-45mm screw in the right hole of the tensioner lever. Use this setup to align the filament driver gear with the 1038-2RS bearing.
Now I am going to stack the parts to make the back half of the extruder body. Just a shameless plug for one of my favorite books, the next few steps would be easier if you are a Motie. First, grab the new one-piece mount plate and insert an M3-45mm screw in the upper-left hole. Put the end vent piece on the screw through the mount plate, and then put the back half of the extruder body on the screw (the back half is the one that doesn’t have any holes in the end for screwing to the cooling fan). Finally, put the filament tensioner on the screw. It should look something like this picture.
I stole a spring from an ink pen. If it doesn’t provide enough tension I will have to print the spacers Laird provides a model for to increase the tension. Put the spring in the place provided, then put the front half of the extruder body on the screw. Now it gets tricky, open the lower part of the body enough to slide in your hot end, through the provided hole. Finally, tighten the screw in the NEMA-17 motor. The second screw is passed through the second hole in the lever, and the final screw goes in one of the bottom holes.
Now you can see how that 3rd arm comes in handy.
Extruder Head Conclusion
Unfortunately, I discovered at the end that this extruder head assembly does not work with my hot end. Apparently there have been some changes made to the hot end; my hot end does not have the cut out in the barrel to lock it in place in the V11 extruder head assembly and it is shorter so the vents extend past the end of the nozzle. I guess I will have to re-assemble the factory head and hope it survives until I can find an alternate upgrade. Sure looks nice though, and I will gain the extra width as I can keep the one-piece mount plate with the factory extruder head assembly.
To see my working upgrade follow this link.