RE: VFA Artifacts on X+Y Straight Edges
I had a look at the belt whilst it was printing the vfa tower. Both axis appeared to be hard against the pully, no wandering at all.
Having a look at the overture pla test I think there are vfa. Ive uploaded a video. At one point I say ripple, I'm referring to the pattern rather than the defect.
https://youtube.com/shorts/y0i6KYXPcyE?si=RZFo_dElRJJX1pXr
Hopefully youtube doesn't butcher the quality as it was determined to upload as a short.
RE: VFA Artifacts on X+Y Straight Edges
I've long since returned my Prusa Core One printer for a refund minus the time and effort for debugging for them but it seemed like most of the assembled models were still giving VFAs, so presumably both pulleys would need adjusting for this to reduce it this much.
Still, it's poor that they claimed they couldn't solve this after I sent it back. They should set these positions in a more robust way.
If anyone who's fixed this, could you try my gcode from the original post and check it for vfas.
https://drive.google.com/file/d/1T7X2J3Gm2UYetzKfY6ZBBM5pxz3wiFaG/view?usp=drivesdk
I’d never read the first few pages of this thread before now but the fact that your printer was returned in Feb? with such clear, obvious VFAs makes the Prusa stance of ‘it doesn’t happen on our machines here’ a bit laughable really.
That’s a printer that was built by them, delivered to you, then returned back to them with the issue. Even if initially the printer left their factory in perfect working order, surely they should’ve looked into, and solved the issue of what’s causing the VFAs in that time.
That's my main gripe with all this…we as a community should be enjoying our new printers…not doing the dirty work in trying to solve this.
This isn’t a startup with a handful of employees we’ve all backed on Kickstarter…this is Europe’s biggest 3D printer manufacturer with >800 employees.
RE: VFA Artifacts on X+Y Straight Edges
Finished printing the VFA tests. There was no noticeable improvement in VFA's after adjusting the positions of the X and Y motor gear to prevent the belt from being over constrained. I've uploaded a video with some fairly harsh lighting to try and make the artefacts look as bad as humanly possible. This also lets you see the print move under lighting which I think is better for seeing them rather than a photo:
Some points:
- Test carried out with Eryone Dual Colour Silk PLA Purple and Black, HF nozzle using This VFA Test
- Confirmed that initially the belts were against the flange on the gear on the X and Y motor, in both cases the belts was riding high throughout range of movement. After adjustments I confirmed that the belt was largely central. The belt did move but there was always teeth visible on either side of the belt.
- After Adjustments I confirmed that the belts were both within the optimal frequency as defined by the Prusa App.
- The bgcode temps are not aggressive enough for the speeds as the test gets faster resulting in the PLA matte-ing up which goes a long way to hiding the VFA. When running the Y-axis tests I did increase the temps manually as the test progressed however there was a decrease in the quality of the points of the star.
- I've got about 250 hours of print time on my Core One so I think it will be well broken in.
My Conclusions (specific to my case):
- In my case the change did nothing. This is not to say it will always do nothing, just that it didn't in my case.
- Whilst I think increasing the speed helps with VFA's (slight improvement on the Y-axis tests where I bumped up the temperatures) this isn't really an answer. If you want high quality prints with a silk PLA you'll be wanting to print at an optimal speed for print quality and shiny which will necessitate slower speeds and optimal temps.
- A qualifier to the improvement is that I think the improvement is achieved because it smears out the VFA rather that stops it. If you look at the prints as the speed increases the artefacts get more spaced out. You can also feel the texture change on the print itself. If the artefacts are related to the belts themselves I would expect that they wouldn't change their appearance in this way due to speed (pure speculation)
- The VFA's seem worst at 30 degrees.
- Looking at @gb160's original post on the fix I would say that my stock quality of print didn't have the same level of artefact as they did before they did the mod, so I think it is possible that and over constrained belt could impact the quality, just that in my case it wasn't in the beginning.
So yeah, no improvement. It doesn't really affect me as I don't print glossy prints often and even when I wouldn't be worrying about VFA's. However, I can absolutely see how if I did and the objects had lots of straight edges (like boxes) then the level of VFA would be unacceptable. Also the VFA test print is phenominal at finding the harmonic resonance of the printer. Once phase steppign is properly live I will absolutely be printing this to see if it helps the noise lol.
RE: VFA Artifacts on X+Y Straight Edges
Finished printing the VFA tests. There was no noticeable improvement in VFA's after adjusting the positions of the X and Y motor gear to prevent the belt from being over constrained. I've uploaded a video with some fairly harsh lighting to try and make the artefacts look as bad as humanly possible. This also lets you see the print move under lighting which I think is better for seeing them rather than a photo:
Some points:
- Test carried out with Eryone Dual Colour Silk PLA Purple and Black, HF nozzle using This VFA Test
- Confirmed that initially the belts were against the flange on the gear on the X and Y motor, in both cases the belts was riding high throughout range of movement. After adjustments I confirmed that the belt was largely central. The belt did move but there was always teeth visible on either side of the belt.
- After Adjustments I confirmed that the belts were both within the optimal frequency as defined by the Prusa App.
- The bgcode temps are not aggressive enough for the speeds as the test gets faster resulting in the PLA matte-ing up which goes a long way to hiding the VFA. When running the Y-axis tests I did increase the temps manually as the test progressed however there was a decrease in the quality of the points of the star.
- I've got about 250 hours of print time on my Core One so I think it will be well broken in.
My Conclusions (specific to my case):
- In my case the change did nothing. This is not to say it will always do nothing, just that it didn't in my case.
- Whilst I think increasing the speed helps with VFA's (slight improvement on the Y-axis tests where I bumped up the temperatures) this isn't really an answer. If you want high quality prints with a silk PLA you'll be wanting to print at an optimal speed for print quality and shiny which will necessitate slower speeds and optimal temps.
- A qualifier to the improvement is that I think the improvement is achieved because it smears out the VFA rather that stops it. If you look at the prints as the speed increases the artefacts get more spaced out. You can also feel the texture change on the print itself. If the artefacts are related to the belts themselves I would expect that they wouldn't change their appearance in this way due to speed (pure speculation)
- The VFA's seem worst at 30 degrees.
- Looking at @gb160's original post on the fix I would say that my stock quality of print didn't have the same level of artefact as they did before they did the mod, so I think it is possible that and over constrained belt could impact the quality, just that in my case it wasn't in the beginning.
So yeah, no improvement. It doesn't really affect me as I don't print glossy prints often and even when I wouldn't be worrying about VFA's. However, I can absolutely see how if I did and the objects had lots of straight edges (like boxes) then the level of VFA would be unacceptable. Also the VFA test print is phenominal at finding the harmonic resonance of the printer. Once phase steppign is properly live I will absolutely be printing this to see if it helps the noise lol.
Interesting, but disappointing results mate. This kind of pushes the notion that the VFAs are caused by a combination of factors..the pulley height being just one of them, it would've been nice if there was one 'magic bullet' fix that solved everyones problems, but I think if that was the case then someone would've stumbled on it before now.
Just as a side note after adjusting the pulley I did perform both Input Shaping and Phase stepping calibration...although from my understanding neither should really be expected to directly affect VFAs. (The phase stepping calibration failed when I first tried it, but a day later it completed without a hitch)
Anyway, back to the day job of printing PETG-CF...the holy land where no VFAs exist (well, not that we can see anyway 😂)
RE:
After I said about the phase stepping I remembered a post about being able to run the phase stepping via gcode so I found how to do that (60% and 40% reduction in vibrations) so I ran the VFA test again. No improvement. RHS test is stock LHS is post phase stepping with me manually bumping up the temperatures to keep it shiny. I also tried loosening the idler which made no difference. Well on the print quality. Happy to report that it has massively reduced the annoying harmonics.
RE: VFA Artifacts on X+Y Straight Edges
I'm a bit bumped by the "resonance ripples" of the Core One.. Mine isn't loud and it's not bad at all, but when not using some mild fuzzy skin, the ripples are visible on all smoother surfaces, even with matte filament.
That said, everything else about that printer is basically perfect and I'm absolutely loving it (after disabling the hotend heating for homing/nozzle cleaning/probing).
My belts are slightly leaning on the flanges of all idlers and pulleys and I didn't do the phase stepping yet. I'm really curious to try all kind of things, speeds etc. and note down all results.
No, a machine like the Core One shouldn't require all this, but on the other hand I really enjoy the process with the community and use matte black with fuzzy skin 99% of the time.
Not much "content" in this post, sorry. I'm towards the end of studying mechatronical engineering, so it's very interesting and fun for me, thanks for everyone contributing!
As soon as my current project is wrapped up, I'll contribute with testing etc. too.
RE: VFA Artifacts on X+Y Straight Edges
No effect at all. Still has VFA
Today i installed toothed idlers, result: none.
Meaning no VFAs or no effect on VFAs?
RE: VFA Artifacts on X+Y Straight Edges
I'm going to order some 1.5mm pitch belts and teeth. Does anyone have a measurement on the length of the belts?
I'm largely doing this because it's an interesting problem, not that it bothers me.
RE:
Please let us know what parts you had to modify and where you got the hardware (idlers, pulleys, belts) for 1.5GT. I'm also interested in trying it. Qidi+4 seems to benefit from it from what I've heard and seen.
I assume the screws will need to either be replaced with thicker shafts or will require an additional "tube" to widen them. The only idlers I've seen for 1.5GT have a wider bore than what Prusa uses. Also the pulley sizes differ even when going to a bigger teeth count, so steps will need to be adjusted for both X and Y.
I'm going to order some 1.5mm pitch belts and teeth. Does anyone have a measurement on the length of the belts?
I'm largely doing this because it's an interesting problem, not that it bothers me.
RE:
I don't one a Core One, but as someone slightly obsessed with belt VFA and how to eliminate it, I've been watching this thread with great interest.
This is clearly belt ripple VFA at the higher speeds, the lower speed more closely spaced lines are most likely motor VFA. I had a Bambu P1S for a while that had bad belt ripple VFA that annoyed me enough to sell it. Not being able to find an affordable replacement with less belt ripple I purchase a Flashforge Adventurer 5m on sale as a machine to experiment on to see if I could improve the typical corexy belt ripple problem.
I changed the 1.8 deg steppers for some LDO 0.9 steppers I had on hand. This changed the lower speed VFA on the problematic angle moves(30 and 60) but didn't really reduce it.
I changed the belts and pulleys to some Aliexpress Powge 1.5GT parts. Easy to do on a Klipper machine as you can quickly change the rotation distance etc in the config. I also sanded the teeth off the belt where it runs over the idlers on the X gantry. This eliminated all belt ripple VFA on pure x moves (0 deg). Other angles still show some belt VFA but it is reduce by at least ~75% on the worst angle moves (30 and 45 deg).
So it's clearly caused by the belt/motor pulley tooth mesh as well as the teeth running over the idler on the x axis. Changing the x axis idler to a toothed version would only help if their meshing was 100% perfect. There is no need for teeth in this area though (at least on some Corexy routings), so eliminating them is the obvious answer if possible. Bambulab run a flat section on their A series belts where they run over an idler.
I remember reading on a forum post that the X1C was originally going to be released with toothed idlers on the x gantry but they found that after some time they made the problem worse due as the belt stretched and the meshing presumably worsened. Some Bambu X1C and P1 users have found improvement by wrapping their idlers in Tessa tape or Teflon tape, which I assume absorbs some of the impact of the tooth against the flat idler surface and reduces the bounce.
So if the belt routing/pulley and idler spacing allows it on the Core One, sanding the teeth off the belt is one option. It's not easy, but it is doable if you are careful. If you want to replace belts quickly, use some heatshrink tubing to temporarily join the old belt to the new one and just pull them through.
Finished printing the VFA tests. There was no noticeable improvement in VFA's after adjusting the positions of the X and Y motor gear to prevent the belt from being over constrained. I've ..
So yeah, no improvement. It doesn't really affect me as I don't print glossy prints often and even when I wouldn't be worrying about VFA's. However, I can absolutely see how if I did and the objects had lots of straight edges (like boxes) then the level of VFA would be unacceptable. Also the VFA test print is phenominal at finding the harmonic resonance of the printer. Once phase steppign is properly live I will absolutely be printing this to see if it helps the noise lol.
RE: VFA Artifacts on X+Y Straight Edges
I've just ordered 4m of 1.5GT 6mm belt and 2 21Tooth 5mm bore pulleys. I don't think there should be any modification required to the machinery. I hope not at any rate. The Core One uses at 16T GT pulley and (at least according to the datasheets for generic parts from Aliexpress) should have an OD on the teeth of 9.68mm whilst a 21T 1.5GT has an OD of 9.79mm so they should line up with the existing holes/slots. The idlers should be okay at 12mm OD on the face the belt runs on. I could swap them out also to some smaller ones (The Core one uses '20 tooth soothless bearings, so can go to 16 tooth which will drop it to about 9mm), but that is a whole lot of disassembly and bearings.
According to chagpt the step per mm with this combo will be close to the Core One as is, so for testing I can just use the shrinkage adjustment to get the parts up to size.
Personally I don't think it'll make a huge difference (my prediction will be that it still has them, just at a 1.5mm pitch) and people will be quick to say that this indicates deeper mechanical issues with the Core One. I'm not so sure though. I would love to see some videos/pictures of the VFA test tower printed with Qidi plus 4, but the only one I've been able to dig up looks oddly familiar to my tests on the core one. I think the VFA tower is particularly brutal
In the mean time I'm going to do some more testing. I have need for some gridfinity bins so I will print baztm's bins ( https://forum.prusa3d.com/forum/postid/751876/) but will also slice a 2x1 bin myself and push the speeds as I think the slow speed in his sliced profile (46mm/s for outside peremiter) will almost certainly make the walls look garbage. More speed and more heat is the answer I think.
In the interim I'm going to look at modifying the testing tower. I think I can safely write off anything below 60mm/s as being garbage. I want to tweak the temperatures so that silk filament remains glossy up to 200mm/s. I'll pick up some monocolour silk to play around with.
Please let us know what parts you had to modify and where you got the hardware (idlers, pulleys, belts) for 1.5GT. I'm also interested in trying it. Qidi+4 seems to benefit from it from what I've heard and seen.
I assume the screws will need to either be replaced with thicker shafts or will require an additional "tube" to widen them. The only idlers I've seen for 1.5GT have a wider bore than what Prusa uses. Also the pulley sizes differ even when going to a bigger teeth count, so steps will need to be adjusted for both X and Y.
I'm going to order some 1.5mm pitch belts and teeth. Does anyone have a measurement on the length of the belts?
I'm largely doing this because it's an interesting problem, not that it bothers me.
RE: VFA Artifacts on X+Y Straight Edges
Did that VFA test just to see how my kit built printer is compared to others, it had significantly less VFA than most pics here, but visible in some angles at lowest speeds. Tried adjusting the motor pulley so it wouldnt ride on the edge, according to the pics shown previously here, it might have made it slightly better in some directions, some not. Then i proceeded to tighten the belts to 90Hz, the left belt was completely off and very sloppy (not measurable by the app), that did at least made a difference, to the worse, So its definitely something with the belts, might loosen them up again to see if it can get better again.
RE: VFA Artifacts on X+Y Straight Edges
Then i proceeded to tighten the belts to 90Hz, the left belt was completely off and very sloppy (not measurable by the app), that did at least made a difference, to the worse, So its definitely something with the belts, might loosen them up again to see if it can get better again.
I'm wondering if there's a "sweetspot" with sloppy belts, where you get perfect surfaces at low speeds.
At higher speeds (or rather accelerations), sloppy belts will result in inaccuracies or even skipping teeth, sure, but if you don't use the speeds anyway due to noise, layer bonding or visuals, I'd be curious to test how low you can go with the belts.
RE: VFA Artifacts on X+Y Straight Edges
@jurgen
I'm not bailing on Prusa, just this particular order. I really like the ecosystem, regular updates, continuous improvement etc. I wouldn't hesitate to buy more Prusa printers when my demand increases, because all of my other Prusa printers just work.
I was buying the Core One to do some more specialized printing.
The Ston Wolf doesn't currently have an enclosure, but I'll either do my own or they have one coming out in July. The current lead time is 5-7 weeks so the enclosure should be ready about the same time my printer ships.
I’ve just pre-ordered a Ston Wolf too - I remembered just in time before the 5% discount expired. The saving almost covered the shipping, lol. I love all my Prusa printers, especially my kit-built CORE One, and was going to convert my MK4S, but have decided to try an alternative instead, and sell the MK4S. That will still leave my MK4+MMU3 which could be converted to a CORE One in the future, depending on how I feel about the MMU3 implementation. The Ston Wolf seems to have plenty of headroom in heating and processing power, and an innovative motion system, and although it’s clearly overkill for my modest hobbyist needs, it’s my hobby and I don’t care!
RE: VFA Artifacts on X+Y Straight Edges
@jurgen
I'm not bailing on Prusa, just this particular order. I really like the ecosystem, regular updates, continuous improvement etc. I wouldn't hesitate to buy more Prusa printers when my demand increases, because all of my other Prusa printers just work.
I was buying the Core One to do some more specialized printing.
The Ston Wolf doesn't currently have an enclosure, but I'll either do my own or they have one coming out in July. The current lead time is 5-7 weeks so the enclosure should be ready about the same time my printer ships.
I’ve just pre-ordered a Ston Wolf too - I remembered just in time before the 5% discount expired. The saving almost covered the shipping, lol. I love all my Prusa printers, especially my kit-built CORE One, and was going to convert my MK4S, but have decided to try an alternative instead, and sell the MK4S. That will still leave my MK4+MMU3 which could be converted to a CORE One in the future, depending on how I feel about the MMU3 implementation. The Ston Wolf seems to have plenty of headroom in heating and processing power, and an innovative motion system, and although it’s clearly overkill for my modest hobbyist needs, it’s my hobby and I don’t care!
I am looking at the Ston Wolf also. I don't need an enclosure, I just need a good printer that has a non-moving bed. I mostly print tall, slim objects, and all the bed-slinger movements make the objects unsteady.
The reason I haven't ordered one, is because I am unsure how well it will work in the long run, since it isn't tested by time the way Prusa printers are - and they don't have the same support system.
I just want a printer that works, and I am not good at tinkering with them. So I just feel the Ston Wolf is an expensive bet. Or am I wrong?
RE: VFA Artifacts on X+Y Straight Edges
@chris hill
I'm excited because it's more how I would build a machine. I'm a mechanical engineer and design stamping dies and special machines, so this is right up my alley. Precision machined plates with all of the locating features on the same plate. The machine beautiful and it's overbuilt, which is right up my alley. I completely understand the mechanics.
The part I'm trying to wrap my head around right now is getting away from the very well laid out Prusa Experience. Prusa does a great job of spoon feeding you, collecting profiles, printer configs, continuous updates, integration into PS etc.
So stepping out into the wild there is more to learn. Klipper, mainsail, fluidd, mobileraker, Moonraker, printer config files etc. etc. There is a lot to learn and understand. I realize that this printer comes with lots of that figured out, but I like to understand everything.
Sorry for the sidetrack. I'm still following along to see what the ultimate resolution is for the VFA.
RE: VFA Artifacts on X+Y Straight Edges
I just want a printer that works, and I am not good at tinkering with them. So I just feel the Ston Wolf is an expensive bet. Or am I wrong?
You may be right. Everything I’ve seen online looks good though, and Nathan clearly knows his stuff! He somehow finds time to respond quickly to emails too. So my gut feeling is it’s a reasonably safe bet.
RE:
@jurgen
I'm not bailing on Prusa, just this particular order. I really like the ecosystem, regular updates, continuous improvement etc. I wouldn't hesitate to buy more Prusa printers when my demand increases, because all of my other Prusa printers just work.
I was buying the Core One to do some more specialized printing.
The Ston Wolf doesn't currently have an enclosure, but I'll either do my own or they have one coming out in July. The current lead time is 5-7 weeks so the enclosure should be ready about the same time my printer ships.
I’ve just pre-ordered a Ston Wolf too - I remembered just in time before the 5% discount expired. The saving almost covered the shipping, lol. I love all my Prusa printers, especially my kit-built CORE One, and was going to convert my MK4S, but have decided to try an alternative instead, and sell the MK4S. That will still leave my MK4+MMU3 which could be converted to a CORE One in the future, depending on how I feel about the MMU3 implementation. The Ston Wolf seems to have plenty of headroom in heating and processing power, and an innovative motion system, and although it’s clearly overkill for my modest hobbyist needs, it’s my hobby and I don’t care!
I am looking at the Ston Wolf also. I don't need an enclosure, I just need a good printer that has a non-moving bed. I mostly print tall, slim objects, and all the bed-slinger movements make the objects unsteady.
The reason I haven't ordered one, is because I am unsure how well it will work in the long run, since it isn't tested by time the way Prusa printers are - and they don't have the same support system.
I just want a printer that works, and I am not good at tinkering with them. So I just feel the Ston Wolf is an expensive bet. Or am I wrong?
Seems to me like he's got it figured out, at least initially, but I feel there will definitely be more tinkering involved if you want to stay up to date with firmware etc. There will definitely be more user tuning required for printing etc. I doubt there will be default printer configs, like .2 structural, .2 speed, .1 detail etc. I think these will be more user created. Hopefully enough people buy it that there will be some community support.
My gut instinct says that Nathan the founder is about to become really overwhelmed, because this printer at this price is going to blow up in my opinion, not literally, but figuratively. The only other thing on the market that comes close to this level of detail imo is the Pantheon, and that's 10 grand.
RE: VFA Artifacts on X+Y Straight Edges
Looking forward to reading peoples experiences 🙂 Because it looks sweet.
I just want a printer that works, and I am not good at tinkering with them. So I just feel the Ston Wolf is an expensive bet. Or am I wrong?
You may be right. Everything I’ve seen online looks good though, and Nathan clearly knows his stuff! He somehow finds time to respond quickly to emails too. So my gut feeling is it’s a reasonably safe bet.
RE: VFA Artifacts on X+Y Straight Edges
The part I'm trying to wrap my head around right now is getting away from the very well laid out Prusa Experience. Prusa does a great job of spoon feeding you, collecting profiles, printer configs, continuous updates, integration into PS etc.
So stepping out into the wild there is more to learn. Klipper, mainsail, fluidd, mobileraker, Moonraker, printer config files etc. etc. There is a lot to learn and understand. I realize that this printer comes with lots of that figured out, but I like to understand everything.
I feel exactly the same. But my journey with Prusa gives me confidence to expand my horizons.