Just in case anyone isn't aware, at some point there was an update to include nozzle change in the printer's menu. Settings > HW Setup > Nozzle Change. This will home the printer > move Z to 200mm, X to the Center, Set the bed to the back > Set temp to 280C. This prevents any thermal anomaly warnings, which is something I was getting. Hope this helps.
SolBro
I would also recommend checking and adjusting z height after this. The new nozzle might not be at same height.
StuffWithKirby
Just did it for the first time on my mk2.5! Tips for other beginners: Remember that not only is the old nozzle hot. Metal conducts heat really good! The nozzle you are changing to as well as the tools quickly heat up. I learned the hard way. Oh well, I have 9 othet fingers ;D
mattiasselin
I can't recommend to replace the nozzle like descripted here any longer!
First reason: after ~10 nozzle replacements, the wires of the heater capsule inside of the heater block just break off because of to much wire bends.
Second reason: after initial loosing of the heat break, you may have the risk to don't get the heat break not tied enough anymore. Resulting that nozzle and heat break don't touch anymore inside of the heat block. This causes leaking of molten filament over time what will causes slidly under extrution and but high chance of blobbing. This is a very slow process! You will not see this directly after the nozzle swap! But weeks or months later you will notice oozing and filament blobs on your nozzle and your heat block.
I experienced both problems above with my Prusa i3 MK3 respective MK3s.
I suggest to swap the nozzle (if necessary) as following:
1. Remove the filament fan and the air directing shroud.
2. heat up your nozzle/hot end as descriped in the video.
3. Place some thing soft but heat resistent on your heat bed to avoid damages by accidentally dropped parts.
4. Move up the extruder unit as descriped in the video.
5. Use a bigger pliers or a variable wrench to hold the heat block as good as possible in it's position! Grab the heat block on the short sides to avoid any contact with the thermistor and heat capsule wirering! DO NOT GRAB THE LONGER SIDE OF THE HEAT BLOCK!
6. Use a socket as descripted in the video to unscrew and handle the accordently nozzle.
7. Screw in the new nozzle as descripted in the video. Hold the heat block in it's position as good as you can!
8. The nozzle should screw in pretty easily, dont use a ratchet to fix the nozzle! Just tied the nozzle by hand!
9. This is importend! Check if the nozzle is not totally screwed in! There have to be ~1mm gab between nozzle tipp and heat block were you see a bit of the nozzle thread.
If the replacement nozzle is screwed in completly there is something wrong! Maybe your new nozzle has a shorter thread then the old one. In that case leaking of molten filament is pretty likely!
10. If the nozzle is screwed in correctly cool down the nozzle and reassemble the filament fan and the fan shroud.
11. Your new nozzle is maybe a bit higher or shorter then the old once. You should run the First Layer Calibration again!
12. If First Layer Calibration doesn't work or the Z-adjustemt values are completly off, you may should readjust the height of the PINDA-Probe. You should check the manual and redo the PINDA adjustment and pre flight check. At this point you are strongly adviced to redo the calibration wizard! XYZ coordinats are most likely pretty off.
If you plan to swap the nozzle more often you should consider to buy at least one spare heat capsule and thermistor probe for the heat block! Each part is about 11€ for a original one but you can get on amazon 5-10 parts from china for around 10-15€
Overall I don't think the nozzle swap is as trivial as presented in this video! You really should think about if it is necessary or not.
marcuswiederhold
Also I'd recommend wearing thin work gloves such as 3M comfort grip gloves, in case the burning hot nozzle bounces off your hand as it falls off.
DheeraVenkatraman
Short, informative and concise. Bravo. Although I would lightly pinch the heater block then do the full tightening with the nozzle.
spikekent
I had to change the nozzle to use Carbon Fiber filaments (MK3s) I chose Nozzle X because it has almost the same thermal profile like the brass stock one. Reading all these comments almost made me renounce. But I decided to give it a try. After taking out the fan shroud I've noticed it was much easier to put the adjustable wrench from the side, 45 degrees down incline, front and back, taking care not to touch Pinda. It literally took me 2 minutes to change the nozzle. And 30 minutes more to run all the calibration procedures. XYZ, PID, First layer.
P.S. I didn't turn the heat block like in this video.
robertradu
I cannot wait until I get enough to get one of your amazing machines. I own a Prusa i3 clone as of now but the real thing in my maker space is going to be so cool!
nicholassmith
The i3 MK3s doesn't allow you to change like this, as the new channel for the wires under the extruder block means there's nowhere to grip the block like at 0:58. This means you have to grip at the front, however then you can't get to the nozzle, and the new fan placement means removing the fan too... And the PINDA probe gets in the way. Then, there's z-calibration to be done after, so all in all, it's about 90 minutes work, plus risk of breaking something, which is why people don't change nozzles.... I think the idea that it's quick and easy is entirely misleading.
wcndave
Using the heater block as a form of tightening or loosening is something I consider dangerous as it can bend the heat break.
ayourk
Thanks, this was a lot easier than I had expected. Hardened nozzle now printing carbon fibre filament. Cheers!
flxfrnzs
Are there any other added steps to ensure that there is no material trapped between the nozzle and the heat break?
DrDuck
Thanks buddy. Was able to change my nozzle without issues.
archy
Guys, you really should replace this video with a new one! 1. You didn't point out that you have to remove the fan nozzle. 2. You will probably bend or even break the heat break if you turn the heat block holding it off-center with a wrench, like you did. 3. You absolutely must check the z-height after this, since there's a good chance of ramming the nozzle into the bed after having it changed.
jonnieZG
vice grips in a pinch but for the love of your printer, don't use needle-nosed pliers
jessejamesb
This works perfectly and without hassle. Changed to a hard metal nozzle for printing XT-CF20. No calibration required.
alexanderens
My mk3 s has more stuff in the way. I have changed quite a few nozzles. Just broke the wire in my hot end this time. There needs to be a dedicated place to attach a wrench or bar to take out the nozzle. Even if it’s just a shot that receives a little bar or something.
Trad
Those pliers are a very bad substitute for an adjustable wrench. If you want to avoid marring the block then a smooth jaw plier wrench really helps.
I wonder if it's too much to have a nozzle swap routine built into the firmware. Cranking the dial to set the temperature gets old.
JeffDM
OK - I followed this exactly step by step.
However, my nozzle now does not have a gap between it and the heat block.
It is the exact nozzle I was previously using. I just took it out to clean it. Then put it right back in - and now there is no gap.
What did I do wrong?
RoadsideRC
I feel like advancements in hot ends have come far enough that manufactures should start looking into adding some ease of maintenance into their designs. The hot end is the most often maintained part of the machine and it should come apart and go together quickly with a single tool or no tool.
That is also the only thing I don't like about the mk3 i3. I know they aren't using a full v6, they have some Frankenstein setup, which is fine except, taking apart the extruder and hot end is a pain in the ass. Like basically the only part of a modern FDM that needs fixing anymore.
