How to replace the extruder nozzle 

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.

I would also recommend checking and adjusting z height after this. The new nozzle might not be at same height.

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.

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! Stop the process, disassamble the extruder unit and then the entire hot end. Adjust how fare the heat break is screwed in the heat block. You may have to screw in the heat break more. Here are a great video discussing the problem and how to fix it: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-FNXYL-3UdOA.html 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.

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.

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

vice grips in a pinch but for the love of your printer, don't use needle-nosed pliers

why are the wires so $*#*$@#*( fragile. destroyed one doing this. barely touched it. TBH the prusa is a great printer but I would never buy another one too much $ and assemble yourself... so much can go wrong

This works perfectly and without hassle. Changed to a hard metal nozzle for printing XT-CF20. No calibration required.

This is a good video I can point people to teach them thanks. I'm guessing this will be the next video. Small nozzle = detailed slow prints Big nozzle = faster less detailed prints Hardened nozzle = for more abrasive materials

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.

Short and really effective video to understand nozzle replacement :O Really good job. Thank you !

If your nozzle has filament on it, it could seal itself inside your socket when the filament hardens. Good luck getting it out.

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.

Using the heater block as a form of tightening or loosening is something I consider dangerous as it can bend the heat break.

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.

this ruined my prusa i3 mk3s thanks josef!

Welp, I overestimated the strength of my left hand when putting the nozzle back. Heat block slipped and I think I've screwed up some of the wires.

Funny thing, if you turn the heat block like that with the pliers you stand a good chance of bending the heat break. Pretty poor instructional video.

Unscrewing the heater block a bit, is in my opinion a very stupid advice. What for? You don’t need to do that, just hold it in place with the wrench and unscrew the nozzle. Basta!

I have been using the same nozzle for 6 years, and I think it might be time to change it lol.

I'm angry this process isn't working for me and I may have damaged the fan and who knows what else because I smell burning. I'm actually quite pissed. Now I'm reading the comments and finding this video is BS.

Please don't follow this video as is, the odds are even if it works at first it's going to damage your printer in the long run. The video is very misleading, changing nozzles is not as easy and there are a lot things that can go wrong. They don't say or show this in the video but PLEASE remove your fan and the fan shroud, It takes very little time and it's going to to protect your 3d printed parts in case the pliers slip and the hot end touches the fan shroud. Point 2: DO NOT use pliers, they can slip and also they are going to scratch the heat block..

There is nothing more annoying than changing nozzles...risk of damaging a lot of stuff. Certainly not 'quick and easy' That would mean: plug n play instead of screwing with different tools at the same time.

great video! love your printers and would like to get one someday in the future! keep on doing your great work

It's thermistor wires not fan wires. Just in case if anyone is wondering what them wire are

"Simple and easy!" except that you now have to check if the nozzle height is the same as before...

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.

I watched the video at the end and then the video at the end of that one and I keep going in circles :(

Hey there, new to 3d printing and trying do my first nozzle change and I've followed the instructions here to the letter but the nozzle wont budge an inch and Im afraid the wrench will slip if I use any more force, any help would be much appreciated.

Are there any other added steps to ensure that there is no material trapped between the nozzle and the heat break?

It works, just did it, but the main problem is just getting access. On my i3, the red cables were basically up against the heater block, and getting a wrench in there was almost impossible. I resorted o using pliers. You also have to keep holding the heater block with the pliers while unbolting the nozzle and while putting it back which wasn't the easiest thing in the world with parts this small and crammed up under the extruder assembly so you can't see a thing and have to do it basically blind. But, got it done. Let's just say that with this first experience with this, I absolutely can - not - wait - for E3D to get their Revo products to market so I can buy them, because this primitive stuff with wrenches is no fun at all.

Could we get an update for this for the Mk3s+? It's harder to find a good angle to hold the heater block without shorting wires on that printer.

i changed my nozzle from an 0.4 to a 0.25 nozzle and on some places on my bed i can see the printbed troughout my first layer. What can i do ?

Tried last night and failed to loosen. My 7mm socket just had a slim screwdriver handle and that was totally inadequate to produce sufficient torque. Today I realised I could attach a 90-degree lever to the socket set. I heated the nozzle to 285 and applied a bit of pressure and heard the click as the nozzle began to turn. Nozzle extracted.

After I did this, the nozzle rammed into the bed. So I had to recalibrate the Z axis AND reposition the PINDA probe. also, plastic was oozing from the top o the heater block. how can I clean all of this? How can I make sure the hotend, and the nozzle are properly installed?

I just tried to change the nozzel on the Mk3s+ and not only does this not match but there is absolutely no ability to do this in the 2 minutes this video shows

And if you touch the wires with the wrench you could short circuit the machine.

Don't bend the what? I bent it. Do I need a new one? Edit: I think it was the heat break. I bent it back straight with my eyeball, did a first layer calibration, and printed myself a whistle. Seems okay 🤷‍♂️

Good GOD I can't wait until I have that Mk4 upgrade kit. This process is a nightmare.

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?

So ever since I replaced the nozzle, the heat block is very loose. How do I fix this?

Wish there was an even easier way to change nozzles, hot swappable. Toolless if possible

What I don't understand is how one can unscrew the heater block from the heat sink since the heat sink is round and not held tightly anywhere??

I Had the problem, that when i tryed to re-tighten the heatblock, the whole heatsink rotated with it, so i could not be tightened. Would be cool if The Heatsink would be held by some screws to prevent that and make tightening simpler.

Highly recommend that this video be updated-- the instructions have been updated to remove the fan shroud for better access, and this video makes no mention of this

Good tutorial!

Nice! really like these informative videos!

This doesn't include all of the steps that are in the manual and on your site. The fan is supposed to be removed first, and then the steps are the same. I had a very difficult time getting the heat block to turn and then an even tougher time getting my old nozzle out. When I finally did, and got the new nozzle in, it was tough to get the heat block back to its original postion. And the red wired also hung donw after replacing the nozzle. I had to try to move them back up. This is not an easy task like it is for my creality machine.

Damn... so the nozzle must not be screwed all way into the block! There is a gap! Good to know.

exactly how big is the gap between the nozzle and the heat block? I'm still having issues with my machine

Would be nice to have a preset for preheating "285 degrees/change nozzle"

Why are so many people commenting about how hard it is in reality to change the nozzle ? I mean, I'm 14 and managed to change the nozzle about 10 times (0.25, 0.4, 0.6, 0.8 mm ). I've had only problems when I tryed it for the first time, this was mostly my fault because I didnt do a coldpull (which is recommended). Dont worry ! It may seem hard, but if you not sure you can maybe ask someone for help. Its *very* important to stay calm.

Please help I changed the nozzle and in slic3r I found where I can change the nozzle diameter but everything else is off as it was preset for 0.4 mm is there a 0.25 mm profile *HELP*

Short, informative and concise. Bravo. Although I would lightly pinch the heater block then do the full tightening with the nozzle.

Is there a proper torque setting for the nozzle on an MK3S?

So I was an idiot and tried unscrewing the nozzle before watching any videos. Thus, I did not heat the printer up. The nozzle was so tight that I ended up cracking it in half. So now half of my old nozzle is still wedged into the box with no way for me to remove it. Is there anything I can do at this point or am I cooked? (Please anyone respond ASAP)

This video is outdated and obsolete. The heater cartridge's wires can easily break using this way. I am not sure if rotating the heater block is the best idea. After a few nozzle changes on my new MK3S+ printer the wires broke. Please make a new video for the process.

I did it exactly this way and now my heater block won't tighten back up. What was the point of loosening the actual block? I'm genuinely curious.

new mk3s+. Few test prints success since out of box. just tried following along , and broke off the nozzle inside the thermistor. :(

do you know the proper torq it required ?

Why is this video still published? It is horrible advice!

what hexagon screwdriver you use ? we got dickhead support at netherlands cause we didnt order printer from them but we do order filaments from them.. they want me charge l ike 16 euro per hour wen their english support can help

Massive pain in the ass, the absolute worst part of this printer

-.- Cleraly its a socket thingy I need. Trying to do this with pliers is clearly not an option for me. XD

I noticed that there is a lot of movement on the hotend side to side on my printer and it looks like it has movement on the printer in the video also, surely this is bad for prints????????????????

If you have no sense of self-preservation like me, you can screw the new nozle in 3/4 of the way by hand

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!

Great way to break shitty little wires on heat block. Loosen the heat block then turn shit attached to it 🙄🙄🙄

This video is out of date. There is no room to loosen the heart block on the mk3s the fan is in the way

Why do you unscrew the heater block before removing the nozzle?

I went ahead and preheated it to 285 degrees and waited for it to heat up. By the time it reached this temperature I started turning the nozzle but it wouldn't turn. Then I heard a beep, followed by the error message ''THERMAL RUNAWAY'' on the LCD panel, and now my nozzle won't heat up.

They should take this down. Very misleading.

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.

First of all, a small release of the heater block caused it to touch the edge of the fan holder and it started to melt. Luckily I noticed it in time and the damage was not great. Second, without a ratchet there is no way to replace the nozzle. I tried with pliers and it didn't come loose even a little bit. I used to have an Ender 3 printer and changing the nozzle was so easy and quick and didn't require any sophisticated tools. Honestly, I'm very disappointed!

10/10, lost and re-discovered a screw, accumulated a pile of wrenches, sockets and pliers, drenched in stress sweat, uttered curses I am not even sure exist, and now my printer yells at me because Prusa does not let you choose a numeric value for your installed nozzle and 0.80 is not in the list of values it cycles through.

"quick and easy" lmao

I ended up changing it by dismantling the entire housing and reassembling it. IDK if there is a reason why you shouldn't do that but otherwise I would recommend beginners do it that way. Edit: keep track of your screws.

Why do you unscrew the heater block before removing the nozzle?

Sheared off the nozzle last time. It doesn't come loose and given how fragile it is I'm stuck. It's broke either way so I guess it doesn't matter. Why don't you pop over to England to the hot end factory and work on this design? It's well past time for it to be fixed.

whats the thing on the extruder shaft for?

You MUST shut down the machine before changing nozzle, you WILL cause a spark by touching wires

isn't it technically the hotend? I thought the extruder is what pushes the nozzle

Thanks buddy. Was able to change my nozzle without issues.

Because I am pretentious (see American) I would like to not use a crescent wrench (spanner). Any chance I could get a metric size of the heater block so I can get the right sized wrench for it? I can not find a ruler with metric units on it in the house...

I'm confused about why there's you have to twist the heaterblock a bit.

I started heating up the hotend and smoke started pouring out of the extruder head. Was that the remaining PLA filament? Was that my extruder? Am I screwed?

If you don't heat up the nozzle how do you fix it?

How about replacing the whole assembly bc a print went bad and stuck on those wires?😬

I tried to change my nozzle for the first time and it's so tight it won't come off, I'm afraid of breaking the heat break, is this normal and do I just need to use more force? I don't think it should take that much strength to take the nozzle out. Anyone else had a similar issue?

I do not understand why to do it hot, since the material expands and it is more difficult to remove and put

Only took ViseGrips and a Milwaukee impact (no joke)...

Which Nozzle do you use for the Prusa printing farm? I am looking for a nozzle for petg that has minimum wear

I got to the part where you unscrew the nozzle and my nozzle broke inside the heat end 😭

What about when your heat break spins, because the only thing holding it in place is clamp force from the plastic housing?

hi,bei mir tritt seit neuem immer wieder das filament am heatblock raus , was mache ich falsch ?

the heaterblock seems a bit loose. maybe 2mm wiggle. is this normal?

"Simple and easy!" except that the brass nozzle sheared off while trying to unscrew it and now I have a printer I can't use. Thanks, Josef, for once again providing substandard parts.

I got a MK3 a month ago and I love it, it's truly an amazing machine. But is there a way to disable the loud beep that occurs when you unload the filament? It's so loud!

Thanks for sharing :-)