I finally did it this way as part of re-checking the print head to ensure there were no lingering effects from the blob back in March (the answer: the plastic bits around the nozzle that house the proximity sensor and fan vent are loose enough to be wobbled by hand, but this does not seem to be a problem as these parts do not contact the print).
The downside of replacing the nozzle this way is that it involves taking off the side plate of the 3D print head, at least according to the instructions on the webste. These instructions are clearly obsolete, so it is probably only necessary to open the flap on the front. If that is the case, then yes, it is worth the extra time to remove the hot end when changing nozzles. Otherwise, the risk of losing those tiny screws for the side panel makes this a bit of a no-go. The only advantage I found to removing the side panel is it makes removal of the hot end much easier.
I bought a bunch of hot ends and have decided to put a special nozzle on each (0.2, 0.6, 0.1, and eventually stainless/hardened nozzles when I move on to other filament types), rather than fiddle with changing the actual nozzle on a hot end.
Thanks for the info. I’m leaving the default 0.4mm nozzle in place for the time being as I find the Ender nozzle change so much simpler and I’ve finally got the Ender bed dialled in perfectly.
I’ve left the drawer project on the back-burner as I’ve been playing with the idea of ‘painting’ with a single nozzle printer. Once I’ve got the bugs out I’ll post a new topic here to see if other folk are interested. One thing I’ll say here is that my method relies on having an absolutely perfect first layer; not the easiest of tasks.
Those instructions are for the original. Unfortunately they haven’t updated the site with SM 2.0 specific instructions.
But it’s super simple:
Open the door.
Loosen the set screw underneath the feeding gear
The hot end should then just drop out (sometimes it seems to get hung up and needs a little (or a lot) of force. Especially if it’s been leaking.)
Carefully pull out the wires until you can detach the connector. Be careful not to pull on the wires and pull out the pins.
Installation is reverse. Just make sure thermistor is seated well in hole, and highly recommended to use some thermal paste.
I have not changed out a nozzle on my print head yet, but figure I eventually will because i want to try a 0.2 mm orifice at some point. When I eventually do it, here’s the procedure I plan to use.
Machine off.
If any filament attached to print head, unload it. then let nozzle cool.
If print head is on machine, take it off but keep cable attached. Lay print head where you can easily work on it with cable still attached.
remove the hot end, (open “door”, loosen set screw, pull out hot end)
pull off silicon sleeve. It’s not easy but can be done. Be careful not to rip it. This might be best done with wire connector disconnected.
if wires disconnected in last step, reconnect them.
with hot end on heat-resistant surface, turn on SM and set nozzle temp to value recommended for installing new nozzle. This might be something like 240 C.
with nozzle at set temp, CAREFULLY grip heater block with pliers and use appropriate socket wrench to unscrew nozzle.
screw in new nozzle, making sure it seats to heat break and leaves same gap between nozzle flat and heat block
Aren’t you going to have to re-calibrate the Z-offset every time you remove the 3-D print head?
The thru-holes on the X-axis linear module are a pretty loose fit, and there isn’t any sort of a register surface (such as a lip on the top of the toolhead that registers against the top of the carriage mount) to guarantee that the toolhead is in the same position as last time. On most equipment, not a problem, but 0.05mm changes seem to make a difference while printing, and there is easily that much play in the toolhead mount.
Then again - changing the hot end, and possibly just changing the nozzle, would require Z offset calibration as well. I guess it comes out in the wash.
I would at least slowly jog down until the calibration card has friction on it, and that should be at Z=0. If it’s not at Z=0, then I would recalibrate.
When I reinstall the toolhead, I try and seat the screws at the bottom of the holes as I’m tightening, and that has proved pretty repeatable, not requiring recalibration.
A shoulder bolt would be ideal. Considered turning one, but all this fussing about with the 3D printer has seriously eaten into my shop time. And, well, the lathe will only consent to making imperial threads
Are you just missing the 25.4 ratio gear to turn metric? As long as you’re careful about your halfnuts and always back up the lathe so that it engages at the exact same spot each time you can turn metric threads.
Well, it’s a 127-tooth gear, and a pretty pricey one too (over three hundred bucks). Yeah, if my back was to the wall I could cut a metric thread close enough to work. I don’t deal with metric all that often.
