Yes i have. Cleaned the Rods, tightened Belts
Is there no way to force a certain speed (higher) on all layers? I can force it to be slower by minimizing that speed, but i canāt force a higher speed.
i now have flipped the print to see if the ringing still happens but now on the top, not the bottom.
Edit: yes it still happens on the same spot after printing the model flipped
Reduce your minimum layer time or increase number of perimeters / infill density. You want more time spent on anything other than the external perimeters so they are sped up.
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this seems to show no effect in the slicer. The layer time only changes when i increase the wall speed.
Left is outer wall at 100
Right is outer wall at 250
Canāt get rid of that middle line either
You need to play with volumetric flow and layer times. You can also go for 0.16mm layer height to increase speed at the same volumetric flow and reducing layer time for layers with longer layer time this way.
Where is this calibration found?
Thanks.
Is this the same as running extrusion calibration when starting a print?
You have multiple things limiting movement speed. The minimum layer time will cap the speed, the maximum flow rate will cap the speed, and certain things like top/bottom surface, interfaces, solid fill will also have varied speed. You can always make your speed slower, but you canāt always make your speed higher. Try to match your displayed colors to the legend it gives and youāll probably find youāre not hitting your maximum specified speed.
2mm VFA caused by the belt are the worst around 120-130mm/s and it looks like your outer wall speeds in the rippling area are very close to that. Go above or below that speed and it will improve.
There are actually 2 types of VFA showing in this picture. The coarse 2mm one is from the teeth on the belt and the other is from the cogging of the motor (Motor resonance rippling [MRR]). The second is far more subtle and generally appears at lower speeds. This is the one Prusa improved with the 0.9 degree motors, but it is basically negligible compared to the 2mm problem that afflicts Bambu printers and changing the steppers wonāt improve it.
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I just recently wrote this in a similar topic (sup Slarm!). This isnāt STRICTLY a Bambu problem (albeit not at all helped by Bambuās design or lack thereof in this case), but more of a CoreXY problem directly caused by the belts commonly used in all of these style of printers. Some, like in the case of Voron I hear, are far easier to mitigate/reduce this problem than others (Bambuā¦) With Bambuās current design, youāll be able to reduce the ringing with some creativity, but youāll never completely eliminate it.
This is because of the way the belt is fundamentally designed. Thereās a reason, as pointed out way earlier in this thread, why the ringing looks almost exactly like the belt. The teeth in the belts cause the belts and subsequently the rest of the machine to resonate as the teeth travel across the smooth idler pulleys. Itās just like driving over washboard on a dirt road.
There are things we all can do to help reduce the ringing. Printing faster is just like driving faster over washboard. The tires more glide over the crests of each bump smoothing out your ride. The teeth on the belt do the same at higher speeds over the idlers. Adding teflon tape to the affected idlers on the X axis also greatly deminishes the ringing because it softens the impacts from the teeth. This is just like reducing your tire pressure to help reduce vibration from washboard. The only solution to washboard is getting rid of the washboard when speaking of a dirt road.
With CoreXY, the only real solution as I see it in this case is to change the design of the belt entirely. Something like a serpentine style belt would completely remove the 2mm VFA as the teeth would instead run parallel with the pulleys, eliminating that pesky vibration entirely.
Of course there are other factors at play (quality of the belt, the belt riding on the pulley flanges, etc), but at the end of the day, the basic design of the toothed belt is the main culprit. Unfortunately changing to a different style of belt would require an extensive redesign of the motion system. For now, itās far easier and cheaper for Bambu to tell you to ramp up your print speed to mask the problem.
CoreXY fundamentally gives you print speed at the expense of quality because of its inherent physical weaknesses such as its sensitivity to vibration. Properly configured bed slingers like the Prusa will always be able to outperform CoreXY in print quality (at the expense of print time) because their motion system works on an entirely different principle (POM wheels or linear rails). The A1 will not experience these particular artifacts because it uses linear rails instead of toothed belts. It just will never reach the print speeds of the X1 and P1. Itās why its print bed is so much smaller on the A1 than other printers. Bambu needed as much weight savings as possible as the entire bed must move along the Y axis rather than just the print head.
If the finish of your prints is absolutely critical for your purposes, then try the teflon trick Slarm used to reduce the ringing by quite a bit. If thatās still a problem, you might have to look at a different style of printer like the Prusa - at least for now until something changes. This is all just my opinion. Iām no scientist! Just an edumakated guess. Sorry if some of you have already read my other similarly written post.
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Just received my printer a couple weeks ago and noticed those artifacts on the X axis. I wasnāt that much concerned at first, thinking it just needed a little more calibration. Well, after more than 10 hours of playing with calibration, belt tensioning, printing parameters, I canāt fix this problem so I now understand it is a common occurence and it wonāt go away.
What buggs my mind is that some people with P1S or X1C do not have the problem, so it shows that some printers are worse than others.
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They all have it. Itās just a function of what you print and how fast. Going fast diminishes the pattern as well as printing matte or semi matte filaments (PLA at high speed is semi matte).
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hello
I got the same problem on the X axis.
Iāve performed in orca slicer a VFA test from speed 50 to 350 (step of 20) with a CHT clone nozzle 0.4 with sunlu PETG red (donāt buy it as it is like a dull red/pink and not so opaque).
results is the sweet spot (where there is no more artifacts) is around speed 150-170 (so picked 160).
I will try to spot some photos later as I got some surprise result with the 0, 45 and 30 degree where we can see a not so nice vibration bande (comming fron the belt dent ?) moving 1 step up on each speed change.
here the test
you will notice the strange vibration band moving up on each speed change on 0, 45 and 30 angle (check the drawed arrows)
damm it! I canāt include image or linl to the image
so here a workaround to see my photo
go to imgur and complete the adress with 3Y7OZ52
so : imgur_dot_com/3Y7OZ52
Iāve been fighting with these artifacts since I initially got my X1C (early KS model). Still fighting with them now. Iāve never been able to solve them.
For me, they are only present on X axis movements, and are more pronounced in the right to left direction (when looking at the machine from the front).
Iām considering ordering a new X-axis assembly and new XY motors to see if it helps.
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it will not help.
you just have to not print below some speed ( avoid 50 mm/s 100 mm/s).
in orca slicer do a VFA calibration test and you will see the minimum speed where the artifacts are not visible.
Man I wish I saw all of this before buying my X1Cā¦ I havenāt seen a VFA print on an X1C that came out perfect which is sadā¦ the best one I have seen was someone putting some tape on the spool/idler to help dampen the ribs rubbing. Wish Bambu would step up and admit this is a design fault and send replacement pieces that help with this. For now I think Iāll have to limit my print speed to 40 as even at 170 while X looks ok, I noticed at a 45 degree angle the banding swaps and moves up to the higher speed area and the 50-150 range looks ok. The only area that looks ok across all angles is <40.
I did order some triangles to try the trick of making sure both sides are equal and squre, but pretty sure that wonāt help muchā¦ but will seeā¦
Think I might try the other hack of putting some tape on the spool which looks to cut the banding in half rough from the pics I have seen.
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I too am discovering a problem with my 1-year-old X1. Iām printing a mandalorian outfit for a friend and the shoulder pads had to be cut in half one was laid in the y direction the other more to the x axis. It doesnāt look bad because it makes it look like itās part of the metallic outfit. The 3mf Iām working with is of a high resolution.
I have read quite a few of these 400 plus posts and increase my silk filament a couple of Celsius, using 4 perimeters and decreased the outer perimeter speed to 100. As a former Machinist it makes sense to me that thereās resonating issues through the carbon fiber rods versus steel rods that run in the y-axis. Speed is created by the lighter weight head assembly and these rods but the trade-off is the quality of finishes on radiuses due to a resonating issues. Since Iāve seen so many ideas that have been posted Iām going to try some of my own simpler ideas (when time allows, gads!). This is (I believe) my first post on the Bambu forums. When I purchased this machine last December there was virtually no where to go to get any help or ideas, glad that has changed. Iām sure Bambu will fully address the issue with a different design in a future machine. Theyāve already been tremendously groundbreaking. Try starting your printing experience with a Ender 3 S1 Pro with an added Sonic pad. Slow, cumbersome, but otherwise predictable. Maybe other manufacturers will note the problem with X1 and P1S (my addition black Friday purchase) and try and have a breakthrough of their own to gain your confidence and lead you in a purchase of one of their printing pieces of equipment in the future.
Just received my two x1c printers a 3 weeks ago, them both now about 40h working time on each one, and noticed those artifacts on the X axis. I wasnāt that much concerned at first, thinking it just needed a little more calibration. Well, after more than all days of playing with calibration, belt tensioning, printing parameters, and test parts printings i canāt fix this problem.
Do you have any advice on what to do, the printers are brand new and both have this problem?
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