Prusa Mk3 kit: when to install 0.25mm nozzle ?  

Re: Prusa Mk3 kit: when to install 0.2mm nozzle ?

The MK3 will be my first printer as well so I cannot answer from experience but I can answer from my many months of lurking on the forums.

First, the nozzle will already be installed on the hotend so you'll have to at least get everything assembled as-is. You cannot change a cold nozzle so that will be another reason to setup the printer as-is first.

Second, starting with the default nozzle limits your potential points of failure. If you started off with a different nozzle and got bad prints, it could be any number of setup issues or the fact that you're using a different nozzle. You would have to go back to the standard nozzle to see if your nozzle swap was the problem or if something else was wrong.

So, start with the standard nozzle, confirm everything works as expected, then, only if you find it necessary, swap to a different nozzle.

Re: Prusa Mk3 kit: when to install 0.2mm nozzle ?

Kit owners should always build as shipped. If you use a different nozzle...

I put all my hot-end parts on connectors so I can swap out hot-ends easily. You may want to print out things to help around the house, 0.25mm is not the right nozzle for that. In my case, I have three full heads 0.25, 0.4 and 0.6, and can swap in 20 minutes...but mostly, it has been a godsend when I get PETG jams and has spare assembly ready to go.

...and WELCOME TO THE COMMUNITY!

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

Thank you justinvoelker and stephanpark for the wise suggestions. I should learn how to walk before trying to run. I'll assemble my Prusa without modification. I can have very small parts ( such as the abovementioned TT scale railroad fence ) printed at Shapeways or ... switch scale .

I thought it ws as simple as unscrewing the 0.4mm nozzle, screw the 0.2mm one and change the nozzle diameter in the PrusaControl software.

Jacques

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

@Jacques
Yeah, I thought that too when I first started. Then I had a massive ABS leak and threw away nearly 30€ in parts, OK not really, was able to remove by dunking in Acetone for a month but bought parts to keep printing meanwhile. So, seating nozzle to brake is critical as nozzle machining isn't perfect and thermal grease needed must be high temperature metal-oxide kind. Then there is the heat cycle tightening before printing...all means it is just easier to have multiple head assemblies and modded printer to quick-swap as I have...but all that is in your future! For now, marvel at the wonder of...the part detached from my bed...and...oh god my printer is on fire...and...tore my PEI bed...why the hell is this so damn slow...what do you mean my thermal is running away! So much fun! 😉

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

Not to mention: " I have two printers so I always have one working...I have three printers so I always have one...I have four printers so I always have..." as nauseum.

It's an addiction,

Neal

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

So my question is: should I assemble the kit with the original 0.4mm nozzle , print some test parts such as 3DBenchy to debug my assembled printer , then replace the 0.4mm nozzle with the 0.25 mm ?
Jacques

I recommend you exactly in this order

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

Thank you stephanpark , neal.w2 and michael.m63 for yours suggestions and humoristic opinions.
I found a compromise so I can print small 1/120 scale parts using the 0.4 mm nozzle : I simply scaled that part to ... 120% and the result , as seen on the PrusaControl screen print looks OK. It is a small detail on the layout so it is unnoticeable ( I hope ) and I still have the option to burry the fence deeper 🙂

Jacques

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

The bicabine steam tramway ( belgian vicinal railroad ) , already successfully printed at Shapeways ( FUD material ) , looks like it will print without 120% upscaling with the 0.4mm nozzle .

Jacques

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

Jacques, if you would like help with modelling skills or the difference from FFF/FDM vs. sintering vs. targeted resin curing, MK3 topic area is not the right place to get input or help. Please start a new topic in an appropriate category so people interested or knowledgeable in that topic will be better equipped to help you. Your chances of getting help is much lower if you post in the wrong place, kind of like going into the ladies room to get a date...wrong place. 😆

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

OK stephanpark I got the message.
I'll start a new topic : Why I don't need to install a 0.25mm nozzle anymore".

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

Hahaha, there you go. 😆
As your question applies to any of the i3 series and frankly all RepRap E3D/clone based printers, that group of people is much larger. Many more ideas and tips to gain.

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

stephanpark, I purchased the Original Prusa i3 MK3 so it iwas absolutely logical for me to ask the question on the ... Original Prusa i3 MK3 subforum. As I'm a curious person I'll follow your suggestion ( thank you ) and ask the same question on a RepRap E3D/clone forum.

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

@Jacques
You may be suffering from temporary narcissism. It happens when one is frustrated and reverts to the attitude of a selfish child. It is OK, we all get that way when we buy an expensive tool or toy and we are afraid we've wasted our money. But, let me show you your error, one doesn't go to a Ford Focus forum to learn how to drive a car. Buying a Original Prusa MK3 doesn't entitle you to private lessons on how to run a 3D printer let alone an MK3. There are driving schools, as well as there are free lessons on how to use a 3D printer as well as how to use many free CAD packages. So your absolute logic is evidence of something less than sound. When you feel calm again, I have an idea to modify the Live-Z calibration code so you can calibrate directly on a clean slate 0.2mm nozzle MK3. As I've found, it is always unpleasant to interact with someone suffering from Buyer's Remorse anxiety so please try to keep that in control while you are uncertain if you've made the right decision in purchasing any expensive item when working with people who are volunteering their time to help you achieve your goals.

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

That was totally uncalled for. We don't need a prima donna blasting away here please.

Re: Prusa Mk3 kit: when to install 0.25mm nozzle ?

@Reid
You're right, that should have been a PM. I've met so many novices in all kinds of topics with bad attitudes particularly due to entitlement from tool purchase that get in their own way it slipped my mind to ask him to search the whole forum first privately. Jacques, my crit of your temporary attitude stands, but I'm sorry I placed my crit so publicly. Shame wasn't the target, aligning perspective was. But it seems as it came off that way so thanks for the gut check.

@Jacques
Google is useful, 3D printing is much more than Prusa Research, many have gone down this road before and much learned my help you in your adventure. This was one of the first links that popped up. 3D Printing with Smaller Nozzle Diameter It is a bit older but captures most of our experiences with odd filaments and smaller nozzles. Point being, this is the first in 40+ found items on your topic. Many are worth reading before posting on the manufacture's official forum about their new and slightly flawed printer. And on that potential flaw, be mindful...details below. I'd advise you don't simply trust the printer when you switch to smaller nozzle. The recovery feature is not as automatic as the marketing states in our case (0.2mm nozzle users with recovery).

@All
On the topic, MK3's firmware restarts are a cause for concern due to the tendency for clogging on shock cool-down and heat up without opportunity to purge prior to continuing print on smaller nozzles. MK3 really should have implemented a scrub or purge protocol in recovery sequence, though as Joel of 3D Printing Nerd said "...a blemish is far better than a failed print". The issue is with small nozzles there is a much higher chance of clogs and blobs causing recovery. A large blob can cause layer skip, which causes a restart, which causes ooze which highers the chance of a bigger blob, etc. etc.

I don't think firmware takes into account the number of retries on said layer. Probably none. The higher end recovery capable printers have nozzle cleaning, it has also been a part of Marlin for quite a while. I think with MK3, Prusa Research should have started facility for G12 which firmware at the moment does not. Could have been a calculated risk but again, smaller nozzle, this becomes more useful. Forcing an operator (I think that is what a person running CNC is called) to hover over the whole print to catch and clean the nozzle on a feature sold as automatic recovery is a bit unfinished. Both Tom Sanlanderer and Joel found out (3D printing centric YouTube channel hosts). Joel is who is surprisingly tactful in his criticism. (I could learn something from that guy 😉 ).