Request:
If anyone is willing to print my 15 minute, 4g model and share the results here, it would be really helpful!
I’d like to compare the VFA characteristics of A1/A1 Mini vs X1 printers.
I’m specifically looking for the vertical lines that show up for X1/P1 across the X axis.
Explanation:
I’ve been struggling with VFA on my KS X1C for over a year and it’s severely impacted the quality of prints I do using transparent PLA especially. I want to figure out if getting an A1/A1 Mini would solve my problem without compromising other elements of print quality.
Still hoping somebody will be willing! I can pay a little to more than cover costs to do a test. Really want to find out if the A1 (or mini) can beat the X1 in this regard.
No infill is ideal - the issue I’m working on is a ripply outer wall surface caused by resonance or belt teeth. If no ripples show up when printing the model without infill, then the problem I’m chasing is not manifesting.
The X1/P1 have it especially on the X-axis. Some people seem to have resolved it by replacing certain pulleys which is a very invasive mod and not guaranteed. I’ve tortured my X1 with almost no change in quality except on the peak resonance band.
Here’s one of the threads about it where I showed pictures of the problem:
The format for the A1/A1 mini is so different I am hoping that it won’t suffer from the same issue and if not, I would get one to print my transparent parts where these ripples are intolerable.
• 1 wall thickness
• 0 top and bottom
• small brim to ensure it sticks
• should be about 8 height range modifiers running from 100mm/s - 180mm/s in 10mm/s increments
Print is running…
For reference - this is the slice running on the printer. I don’t expect VFA and you will ask regarding the speed steps so let’s get it out of the way first
And here is images of the result. Tried my best to capture irregularities. To the naked eye + magnifying glass even changing lighting to see the worst, there is just smooth straight walls and no discernible difference between speeds.
This is wonderful! Thank you so much for taking the time to do this test. I can see a hint of VFA on the front of X and nearly nonexistent on Y, but compared to both my X1s, it might as well not be there at all.
I think I saw mention that the A1 series has belt teeth-over-smooth pulleys too, so it seems that the teeth always manifest but this format does it a lot less. It definitely looks uniform rather than having certain especially bad bands as on X1.
The A1 mini doesn’t - not sure about the regular A1!
Mini has 1.5mm pitch belts with flat idlers but the belts only have teeth on the section that engages the driven pulley and are machined flat on the area that rides the idler.
Gimmicky solution to a non-issue (toothed idlers are engineering standard and just work) producing a new issue: The movement of the X/Y axes is non-linear generating errors of up to ±1/10 mm depending on the position along those 180mm of range the mini has.
I guess that’s how bambu ticks in the mechanical department - complicated ‘novel’ ideas for little gain and blind to obvious negative side effects. Same with that carbon rod business…
The A1 mini doesn’t - not sure about the regular A1!
Mini has 1.5mm pitch belts with flat idlers but the belts only have teeth on the section that engages the driven pulley and are machined flat on the area that rides the idler.
This is such a janky solution - I was under the impression they had a smooth section of equal thickness to the teeth which would maybe have less impact. I’ve wrapped gaffer’s tape around my belt to test and seen the sort of deflection it causes firsthand.
Gimmicky solution to a non-issue (toothed idlers are engineering standard and just work)
Why they wouldn’t just use the right parts blows my mind really. I’m also personally really frustrated by the belt fastening system for the X1/P1. Yes, it saves space, but it’s extremely fiddly and I broke the retaining post on my toolhead removing a belt which resulted in having to replace the entire X-axis!
If anyone with an A1 is willing to run the same test, I will extend the same offer for a bit of compensation for time and material or I can donate to the charity of your choice as well!
I’m sorry - actually they do. Just checked the replacements I ordered some time ago: The flat section isn’t machined either and has the same skin as the back.
I was going by what I saw in the printer when I opened it to check what was going on with those jumps in the travel. For some reason the original Y belt in the printer was reddish on the flat section thus my assumption it was machined. I guess the skin is already worn or they changed things during production? No idea…
change the title - something like ‘WANTED:…’ to get more views
provide a ready-to-go 3MF file for the A1 printer with Bambu PLA along with a slicer screenshot
maybe even upload to makerworld so the whole ordeal is a one-click business plus taking few pictures of the result
mention that it’s a few minutes print and less than 5g of PLA
pack it all in a few lines of short, easy to read & structured text (bullet points) at the top and add the background info (most won’t even care) separated below as an optional read
=> make things effortless and easy to grasp
Changing the whole first post accordingly would make sense. Also, you already have a test of the mini - not sure why you ask for another one.
FWIW that’s how it comes out on my X1C, no difference with the various speeds. (the “grains” are because it’s a (poor) glow in the dark filament, closest I have to clear PLA)
Yes there are lines mostly on one axis but to me it’s barely noticeable to the eye unless you’re looking for it and have just the right angle, and the layer inconsistencies in the posted A1 print that aren’t present here would be way worse IMO
Good points! I have revised the original post using most of your recommendations. Can’t use the Bambu Basic PLA setting because it knocks the layer time down to 6s which caps the speed severely.
Also, you already have a test of the mini - not sure why you ask for another one.
Each of the 4 X1Cs I’ve tested produce different levels of VFA with different speed peaks. It’s possible that a single printer happens to be one of the best ones and could misconstrue the typical quality of the model in general.
