J-Head adapter for Solidoodle 2
by enginuitor, published
This is a two-piece adapter that allows a J-Head MkV to be securely mounted on the "Jigsaw Replacement Extruder mk3" by lawsy et al. It can also be used to mount the original Makergear-style hotend without the plywood plate (which I've always found rather inelegant anyway).
Note that this design occupies the mounting bosses normally used for the accessory mounting system. Then again, now you have the plywood plate mounting holes at your disposal...
(If you haven't yet, print out the jigsaw extruder replacement:
Print the model with fairly heavy fill. Have a sharp hobby knife handy for touch-ups.
Test the fit of both pieces against the groove in the PEEK cylinder. They should fit fairly snugly and hug the outer radius.
Now test the fit of both pieces in the slot in the lower extruder piece. Again, they should be snug, but not so tight that you have to distort the extruder piece to get them in.
// I found that some very minor whittling was necessary to clean up the the features that grab the cylinder, mostly around the thin pointy bits at the sides (which came out slightly warped).
Press-fit the small insert into the back of the lower extruder block, and [re-]mount it on the stepper motor. Slide the J-head into the slot and rotate it into the desired position, as it will not be able to rotate once clamped in. Finally, mount the front retainer piece: push it into the slot in the extruder, and secure it in place with self-tapping screws. You will probably end up with a gap of 0.5mm or so between the retainer bar and the face of the extruder. Verify that the retainer is properly seated against the insulator. For extra snugness you can tighten down the screws until the retainer bar bows ever-so-slightly, but this will likely cause some crazing on the front face.
Important! Potential carriage crash!
After removing the plywood plate, you will likely find that there is nothing to trip the arm on your X limit switch. I got around this by extending the switch arm with some scrap material. A better solution would be to put a feature on the front retainer that reaches around to trip the switch. I will address this in a future revision.
Enjoy printing with a hot-end that doesn't clog every time you look at it funny!