MK4S: What Nozzle to choose ?
Hello,
with the MK4S kit I received the new Nextruder CHT nozzle, that was installed during the upgrade, replacing the Standard Nextruder brass nozzle.
However weeks before I received the upgrade, I saw the announcement about the new Genuine PRUSA High Flow Nextruder on the E3D site, so I though that it could be a good idea to purchase some spares, since in the PRUSA MK4S update there is only one CHT.
But the surprise come when I had both the nozzles in my hands: they were completely different 😦 When I purchased them from E3D I though it were the same product than the PRUSA shipped, but they weren't.
First difference is in the name:
- The PRUSA shipped, is named NEXTRUDER PRUSA NOZZLE CHT, while the other is named E3D HIGH FLOW BRASS PRUSA NOZZLE.
In the PRUSA knowledge we can read that they ship the MK4S with the Bondtech CHT (Core Heating Technology) nozzles. They do not mention E3D.
- Is CHT synonym of High Flow Technology ? Why they did not just call it HF ? May be HF and CHT are trademarks and can't be used freely. 🙄
- On the PRUSA shipped, the box is a clone of the E3D one, but with the label PRUSA Research.
- On the E3D one, on the bottom of the box, there is another small label: Including BONDTECH P) (may be P stand for Patent)
- So, are both they HIGH FLOW NOZZLES or one of the two is more HF than the other ?
Second big difference: the shape: (click on the picture to see also the PRUSA nozzle)
the E3D nozzle has much bigger brass part to keep the heat, and it seems a real big volcano, while the PRUSA version is still small.
Even if the nozzles part seem different, stating to E3D:
These high-quality 3D printing nozzles are designed specifically for use with Prusa’s latest extruder – Nextruder. Compatible with Prusa’s MK4 and XL 3D printers, they feature an all-metal filament guide which means that Nextruder’s filament path is entirely metal. This helps improve overall printer reliability and enables speedier nozzle changing.
Higher Flow. E3D Prusa High Flow Brass Nozzles increase your setup's volumetric flow rate, enabling you to print faster!
How does this work? Unlike our previous E3D High-Flow Hotends (Volcano and SuperVolcano), E3D Prusa High-Flow Brass Nozzles maintain the exact same form factor as standard E3D Prusa Brass Nozzles; this means there is no need to adjust your pre-existing mount and fan duct setups!
E3D Prusa High-Flow Brass Nozzles use a unique custom internal geometry to increase the surface area for improved thermal transfer to the filament.
For now I am testing the MK4S with the shipped PRUSA CHT, but once I will have an idea of the results I will try also the E3D HW.
- Have someone of you already tried the E3D HF ? 🤔
Regards
RE: MK4S: What Nozzle to choose ?
Careful when ordering HF nozzles. They're more than anything a marketing ploy used by manufacturers to boost their sales. You must realize that the flow increase over ordinary nozzles is not big ( marginal, I'd say) because the main factor dictating the flow is the power in watts of the heater cartridge and, to a lesser extent, the material of the hot block and nozzle (copper better than aluminum or hardened steel). Besides, HF nozzles have, in my opinion. a huge drawback. If you get a clog, good luck cleaning the inside of the nozzle with cold pulls or acupuncture needles. In top of that, they're more prone to clogs than the others, specially printing filaments with solid particles. because of their internal geometry with several narrow paths instead of a single bigger path.
RE: MK4S: What Nozzle to choose ?
Careful when ordering HF nozzles. They're more than anything a marketing ploy used by manufacturers to boost their sales. You must realize that the flow increase over ordinary nozzles is not big ( marginal, I'd say) because the main factor dictating the flow is the power in watts of the heater cartridge and, to a lesser extent, the material of the hot block and nozzle (copper better than aluminum or hardened steel). Besides, HF nozzles have, in my opinion. a huge drawback. If you get a clog, good luck cleaning the inside of the nozzle with cold pulls or acupuncture needles. In top of that, they're more prone to clogs than the others, specially printing filaments with solid particles. because of their internal geometry with several narrow paths instead of a single bigger path.
I agree with this. I do tis HF nozzles are a bit over-rated. I'm tempted to go back to standard with my MK4s - just waiting for an excuse, ie the slightest hint of any issues and I'll switch without hesitation.
--> MK4 - MK4S - MINI+ - MMU3 - Accelerometer Guide - BambuLab A1 Combo <--
RE: MK4S: What Nozzle to choose ?
Considering reverting to my Diamondback if there is no measurable difference in speed myself.
RE:
- Is CHT synonym of High Flow Technology ? Why they did not just call it HF ? May be HF and CHT are trademarks and can't be used freely. 🙄
AFAIR, CHT is a registered trademark (by Bondtech for their patented nozzle internal geometry) and HF is a generic descriptive of nozzles designed for high(er) flow than standard nozzles. Volcano nozzles are high flow by providing a longer melt zone, CHT are higher flow by splitting the filament path to increase surface area. My personal mental analogy is: CHT are the squares of HF rectangles of nozzle parallelograms.
I'm not sure how the E3D Nextruder high flow nozzles do it (but I do recall hearing that they licensed the CHT geometry for some of their Revo nozzles). Maybe they used the same license from Bondtech for CHT on the Nextruder nozzles? Or maybe they came up with their own technique to get around the Bondtech patent?
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RE: MK4S: What Nozzle to choose ?
... HF nozzles are a bit over-rated. I'm tempted to go back to standard with my MK4s - just waiting for an excuse, ie the slightest hint of any issues and I'll switch without hesitation.
After a few days with the MK4S and HF 0.4, I have switched back to a regular 0.4 nozzle.
I print almost exclusively PETG. I have had my MK4 since Jun-2023, and never a single issue printing PETG. Specifically, I have had NONE of the "common" PETG problems with stringing, filament building up on the nozzle, turning black, and being deposited somewhere on the print. I use Prusa's default print profiles and keep my filament dry. Fantastic results for over a year, every single time.
But with the 0.4 HF nozzle... I have repeatedly had burned filament blobs get deposited on prints. In one case, the blob was big enough that the nozzle hit it on the next layer and induced a layer shift -- ruining the print. That's using the default Prusa HF profiles, and dried Prusament filament. I reverted to the 0.4 nozzle, resliced for the old non-HF MK4S 0.4 profile, and restarted. Everything printed perfectly with the non-HF nozzle (same filament, same models).
Since then, I've switched back and forth a few times to test. The 0.4 HF nozzle gives me problems with PETG, while the 0.4 standard nozzle works perfectly. The HF may work fine with other filaments (i.e., PLA, ABS, ASA, etc.) -- I cannot say because I haven't tried them yet. But over 90% of my printing is PETG, so I need a setup that works well with it.
My "best guess" is that the smaller channels in the HF nozzle make retraction work differently, and retraction settings need to be tweaked. But that may not be easy, since the nozzle type (HF vs. regular) is in the Printer settings, but the retraction settings are driven by the Filament settings (via Filament overrides of the printer setting defaults). I don't really want to spend the time creating and testing separate filament profiles for HF vs. non-HF in hopes that I can fix the issues. It's easier for me to just revert to the 0.4 non-HF nozzle for now.
Maybe Prusa will add separate HF and non-HF retraction settings within the filament profile, or maybe they will find some other way to mitigate the issue. But for now, I've gone back to the standard non-HF nozzle. I did try out the "0.25 layer height" provided by the HF profiles and the extra speed was nice, but not nice enough to outweigh having a print with numerous blobs (or a failure due to layer shift).
Still happy with the MK4S upgrade, because the improved cooling is helpful with PETG. But for me, at least with PETG, the HF nozzle has been nothing but trouble.
RE: MK4S: What Nozzle to choose ?
I'm also going back to my old nozzles, in my case Obxidian. In my hands, I didn't see any meaningful speed improvements while preserving the same level of quality, so I'd rather go with the "no need to worry about it anything" Obxidians.
In retrospect I should have skipped the upgrades as I'm really not getting anything out of it. I design most models myself and take care avoiding overhangs so the improved performance of the new fan doesn't help me. And compare to the old fan, which was elegant and functional, the new design is an abomination. To see what's going on, you have to kneel in front of your printer.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: MK4S: What Nozzle to choose ?
... the new design is an abomination. To see what's going on, you have to kneel in front of your printer.
That is a really good description, LOL. Especially with small parts, it is almost impossible to see how the current layer is printing.
RE: MK4S: What Nozzle to choose ?
the new design is an abomination. To see what's going on, you have to kneel in front of your printer.
Agree!!!!!!
--> MK4 - MK4S - MINI+ - MMU3 - Accelerometer Guide - BambuLab A1 Combo <--
RE: MK4S: What Nozzle to choose ?
Abomination seems pretty strong :), but you are right. In another post I called it a "failure shield" because if there is a print failure, you are not going to know it for a long time with that fan in the way.
By the way, today I took off my HF nozzle and put my Diamondback back on. It simply prints better, and I'll take the speed hit.
However, to be a bit more positive, I would have paid the $99.00 for the ability to print much sharper angles without supports, which most certainly works with this upgrade. Supports have essentially ruined (or I have ruined taking them off) many prints. I am able to print items without supports now that I never could, so worth the price to me.
RE: MK4S: What Nozzle to choose ?
I am having the same observation. If slicer would have same calibration test build in like orca then i would give a try. Current situation is like wtf they took money and sold stuff which is not working as advertised.
mini+ [bondtech dual drive, revo, reprinted with PA11-CF and ASA] lives in photo tent.
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RE: MK4S: What Nozzle to choose ?
Wow, so I'm not alone in having issues with PETG and the HF nozzle. I tried both the 0.4 HF that comes with the MK4S, and the ObXidian 0.4 HF and both were giving issues with getting good PETG prints, lots of burning of PETG, which is not something I had previously experienced on my MK3S. PETG was one of the better materials to print with on it. Switching over to a non-HF nozzle and seeing how things print.
RE: MK4S: What Nozzle to choose ?
I ran into similar issues with 2 out of my 4 MK4s printers. I also have an MK3.9s with a Prusa HF Nozzle that came in the upgrade kit. I print primarily PETG. On two of the printers, I was getting consistent "Stuck Filament" errors after a good first layer. I should note that one of the MK4S printers is factory new and one was upgraded from a MK4. One other factory new MK4S is running fine with the HF Nozzle. I tried shutting off stuck filament detection but was getting a birds nest after the first layer. I switched the nozzles into the two problem printers and resliced and printed without any issues. What is confusing is that the other three printers with HF nozzles seem to be fine. I should mention also that I tried swapping in an E3D HF Nozzle with the fatter brass piece and I still got stuck filament errors. I'm using creality PETG which is not the most consistent diameter, but for now, the standard flow nozzles are working and I only lose an hour on a 14 hour print.
RE: MK4S: What Nozzle to choose ?
According to the data, this is false - it takes only a tiny amount of power to melt an additional few mm3/sec. The majority of the heat is lost - up the heat break, out to the env through the sock.
CNCKitchen also published really accessible data here - he showed that, with a sock on, you have plenty of headroom on the stock 40w for a cht (or volcano - the also note CHT outperformed volcano in most cases) https://www.cnckitchen.com/blog/bondtech-cht-high-flow-nozzle-reviewed
RE: MK4S: What Nozzle to choose ?
According to the data, this is false - it takes only a tiny amount of power to melt an additional few mm3/sec. The majority of the heat is lost - up the heat break, out to the env through the sock.
CNCKitchen also published really accessible data here - he showed that, with a sock on, you have plenty of headroom on the stock 40w for a cht (or volcano - the also note CHT outperformed volcano in most cases) https://www.cnckitchen.com/blog/bondtech-cht-high-flow-nozzle-reviewed
What's false??? What are you responding to? Did you even read the thread?
There is only one message here I see questioning the melt rate. That isn't really the issue being expressed here, so "according to the data" your comment is irrelevant.
It is definitely NOT False that many people are experiencing problems with the HF nozzles. None of those seem related to not melting the filament quickly enough, but rather with other issues (perhaps flow rate or oozing). Please read the thread.
RE: MK4S: What Nozzle to choose ?
I continue to struggle with petg and hf nozzles. I am continuously getting filament stuck faults after the first layer.
RE:
According to the data, this is false - it takes only a tiny amount of power to melt an additional few mm3/sec. The majority of the heat is lost - up the heat break, out to the env through the sock.
CNCKitchen also published really accessible data here - he showed that, with a sock on, you have plenty of headroom on the stock 40w for a cht (or volcano - the also note CHT outperformed volcano in most cases) https://www.cnckitchen.com/blog/bondtech-cht-high-flow-nozzle-reviewed
What's false??? What are you responding to? Did you even read the thread?
There is only one message here I see questioning the melt rate. That isn't really the issue being expressed here, so "according to the data" your comment is irrelevant.
It is definitely NOT False that many people are experiencing problems with the HF nozzles. None of those seem related to not melting the filament quickly enough, but rather with other issues (perhaps flow rate or oozing). Please read the thread.
Whoooaa buddy. Apparently mobile dropped the actual > quote .... I'll see if I can fix it for you above. (ETA: Nope, apparently the edit window is short) In the meantime:
I was responding to the post above, which states:
Artur5:
"You must realize that the flow increase over ordinary nozzles is not big ( marginal, I'd say) because the main factor dictating the flow is the power in watts of the heater cartridge"
which is entirely false & misinformation, albeit a common misconception about how heat transfer works. The actual increase in available flow is shown to be around 2x, and the heater is not generally a limiting factor at all assuming you follow other best practices (namely using a sock).
RE: MK4S: What Nozzle to choose ?
Whoooaa buddy. Apparently mobile dropped the actual > quote ....
My apologies. Without the quote, I misunderstood and thought your reply was dismissing all the issues reported in the thread, not just responding to that one post regarding heater capacity. We're on the same page. 🙂