Bambu printers print flawless if you stick with 0.4 mm nozzle & PLA. Printer profile for other nozzle size 0.6 and 0.8 are just roughly tuned. I haven’t used 0.2 mm nozzle yet, so can’t speak for it. 0.6 & 0.8 profiles print okay for PLA, but any other types are a hot mess.
For the longest time, I couldn’t figure out why 0.6 mm prints have gaps and bubbles no matter how well the filament is tuned and how long I dry them. It turns out retraction parameter in printer profile is a major factor and among settings like temperature and speed.
I finally printed the exact same sliced model with the same filament Bambu ABS in the same environment. These two were printed one after another.
PETG-HF or PETG in general print okay with 0.6, as long as the part is small. Large parts that take over 2 hours to print suffer quality issues. PETG-HF 0.6 nozzle big gaps at the seams
Sure, most people regularly use .4 nozzles. I used a 0.6mm nozzle for many months and I never encountered the mentioned issues in this post. The reason why I now exclusively use a .4 nozzle, is that most print profiles on makerworld are for 0.4mm nozzles (-> no printing from the app) and in my experience for most models the 0.6mm nozzle will take longer to print and use more material than the 0.4mm nozzle. This is because of the limits of the nozzle heater, the printer has to slow down with a 0.6mm nozzle, but because of the increased line width, more filament will be used.
Sometimes a larger nozzle makes things much easier.
Like for large and strong parts of simple design.
If need be you can get 3mm walls with just 3 wall loops…
Infill is really strong as well…
But of course Bambu did not do too much work in the profile departments LOL
When I tried a cheap 0.6 hardened steel nozzle for glow PLA I was stunned.
First by how easy it printed compared to the 0.4 then again by how unacceptable the print came out.
Did a lot of tuning on the default profile but it never got as good as with the 0.4 - despite the struggles it had to deal with this heat creep filament…
If all possible solutions fail than the impossible must be the fix…
It was back then when I realised that the Bambu nozzle profiles are fundamentally flawed.
Everything seems limited to the 0.4 nozzles while larger and smaller is so badly tuned that printing turns into frustration for no reason.
Let me try to explain the conundrum here:
If you fully calibrate your filament then of course it SHOULD not matter at what layer heights you print.
Needless to say that it does as most people won’t calibrate their filament using 0.1 or lower print profiles…
So while at 0.2mm layers you might not see any meaningful issues switching to o.08 for great details often fails to impress.
Sadly it seems impossible to properly calibrate the flow ratio to work for all layer heights and the corresponding flow rates.
There is no compensation for the ‘cooking time’ in the melting chamber…
The higher flow with a 0.6 nozzle is not as much of a problem as it is for a 0.8mm one.
We need a certain pressure in the melting chamber and we can only run as much filament through it as the heater is able to deal with.
With a max of 48W the heater is underpowered for high flow needs.
Calibrating the flow ration for a bigger nozzle is not as easy either.
You need a larger test print as the filament stays how for longer.
If you used the standard cube for an infill calibration you need it at least 5 by 5cm for the 0,6mm nozzle.
Don’t be surprised if the calibrated flow ratio for the 0.6 is very different to the one for 0.4…
Here is something worth to think about:
I use a high flow hotend as my default option.
With PLA and the 0.4 nozzle I have no issues reaching print speeds in excess of 400mm/s and max flow rates between 35 and 40.
For combined infill of certain types I max out the max of 40.
At these rates the extruder and AMS feeder go nuts in terms of transport speeds.
If I do a print suitable to reach top speeds and flow rates using the high flow 0.4 I still get lower print times than trying the standard 0.6 hardened steel hotend.
Simply because I can reach much faster print speeds.
IF I would have a high flow 0.6mm hotend I highly doubt the extruder and AMS would be able to keep up.
An area of about 0.13 square mm for a 0.4 nozzle.
About 0.28 for the 0.6 nozzle - more than TWICE the area.
Leaves only distance to make it a volume…
More than twice the area means more than twice the speed is required from feeding system.
All related parameters depend on these speeds being ACCURATE.
There is two problems here:
Bad defaults provided and no great ways to properly calibrate a filament so it works the same no matter the layer height or nozzle size.
I started 3D printing when all we had was 3mm filaments, later the standard was 2.85mm LOL
You can imagine that our extruders were rather huge compared to the modern ones we have today.
Rather than a lot of speed we actually required a lot of torque to get this thick filament through and also massive heat blocks to melt it quickly enough.
My standard nozzle was a 0.8 but I also had 1, 1.2 and 0.7 nozzles at my disposal.
Never had any issues swapping nozzles and getting the same great print quality.
Well, great is relative considering the vintage state …
So why is it so hard today?
Because today or firmware and slicer can do soooooo much more.
More speed, higher accuracy, better calculations, more factors considered…
Change the oil when needed, the filter as well and your Beetle just keeps on running forever!
A modern car not so much - same for our printers
They need constant tuning and TLC LOL
Here is my result printing with 0.6 vs 0.4 nozzle using PETG HF. This doesn’t happen with other filaments like Rapid Elegoo PETG. I haven’t played around with the slicer settings much like retraction and such.
For me it Looks you have to recalibrate the Preyssure Advantage and it also make Sense to every fail picture, and also technically another Nozzle size needs another PA. Because the nozzle Preyssure in .6 falls much faster than .4 thats why all showed prints Run Out of Filament.
Because the Error are clearly Not enough Filament.
So If you Switched everything correct, there must ne a bottleneck that you dont get enough Filament (or Heat?) die you calibrate the params in the right Order?
Higher or lower than what? I just ran the max volumetric speed test like I always do, then I deducted 10% from the result I got. One thing I can guarantee though, is that these zits are not related to max volumetric speed, simply because I was printing something small, and I have minimum layer time set to 10 seconds, so it was actually printing very slowly (less than 80mm/s).
I reduced retraction, and the surface got much better, but I still wasn’t happy with the inconsistency of the layers. I also tried increasing the temp, knowing it wouldn’t do anything because I was printing fairly slowly to begin with.
And I calibrated the filament in the correct order.
At any rate, I actually gave up trying to get good prints with the 0.6 nozzle and went back to a 0.4 CHT high flow nozzle.
I actually got tired of troubleshooting the 0.6 nozzle issues and went back to 0.4. But yeah, I haven’t noticed much of a difference between Rapid Elegoo PETG and Bambu HF PETG when using a 0.4 nozzle. But when I switched to 0.6, I managed to get great results on both Elegoo orange and Bambu red colours, but not Bambu white. The pic below of the Bambu PETG HF red. So I don’t get what that’s about. I used the same profiles for these, but again, I just changed those few settings I mentioned earlier.
@Malek you have to Unterstand what physikaly Happens there…
All the params (retraction, Preyssure Advantage, flowrate…) are calibrate to .4 If you Switch the Diameter you have to recalibrate all of them.
Because all of this params Work with the pressure inside the hotend wich hast totaly other Charakteristics than .4…
And yes this makes holes and zits zits from the retraction (.6 need more) and holes from the PA (Pressure and Material goes Out faster than.4)
The volumetric Speed at .6 is physikaly Higher than .4 but a Higher volumetric is Harder to handle thats why iam asking. So try it lower and calibrate everything for .6
Oh of course I calibrated the filament to the new nozzle size (it’s my 10th 3D printer since 2013, lol ). That’s the first thing I did after swapping nozzles and before I printed anything. I did all the necessary calibrations (max volumetric speed, flow rate, and pressure advance). But as indicated earlier, my layer speed was under 10 seconds, so the max volumetric speed was not affecting the print at all since I was printing way slower than the maximum allowed speed.
Those zits are impressive in a negative way.
I mostly use the 0.4mm nozzle. When doing lithophanes, the 0.2mm one, and for all demanding engineering filaments and PLA(40%wood), the 0.6mm nozzle. So, I don’t have a comparison term as you. Next time I change the nozzle, I will give it a try to satisfy my curiosity.
The 0.6mm profiles aren’t as optimised as the 0.4m ones (personal opinion). I think there were improvements over time, as I struggled to get the PAGF flow rate and PA calibrated the first time.
I noticed that you are trying many settings to improve the print. Is it that hard to create a reliable (not excellent) print profile for the 0.6mm nozzle? From my experience (not as extensive as yours) with older printers, it may take the same time, but it is doable.
What is, in your opinion, the issue with the printer (software or hardware) that limits the development of one?
I’ve still got tons to learn, and I do hope I’m wrong about this, but I really do not think creating an “optimized profile” for the 0.6mm has anything to do with the problem, despite the fact that this is what I keep reading everywhere. It really shouldn’t be that difficult to change a few settings and have the printer print reliably across different nozzle sizes. I’ve done it on my Prusa printers. My MK3S and MK2S still print like a dream 7+ years later, whether using a 0.4 or 0.6mm nozzle, without even having to change any settings (except the obvious ones like line width). 3D printers should be quite forgiving between nozzle changes. Granted, none of my other printers is high speed, so it might not be a fair comparison. I suppose slowing down the Bambu to 80-100mm/s to test the quality will provide more insight. And I don’t print PETG on my other printers, so there’s that as well.
I think the issue is either firmware or hardware. I’m hoping it’s the firmware because that would obviously be easier to fix with updates. But it could also be hardware (I hope not). All that being said, I have switched back to 0.6 yesterday again and printed a Bambu orange PETG HF filament, and have not experienced any zits, BUT, the z-banding is terrible (compared with 0.4). The parts look ok but nowhere near as good as 0.4. So I’m probably going back to 0.4 again.
). That’s the first thing I did after swapping nozzles and before I printed anything. I did all the necessary calibrations (max volumetric speed, flow rate, and pressure advance). But as indicated earlier, my layer speed was under 10 seconds, so the max volumetric speed was not affecting the print at all since I was printing way slower than the maximum allowed speed.