Makes me wonder if some of the odd bowing is actually coming from the stamping. Not at all my area of expertise, but from reading, it certainly sounds like stamped parts are very likely to have weird surface shapes due to the stresses imposed on the metal in the process. While there are high precision methods of stamping out flat parts, they would require specialized equipment – read “they cost a whole lot more”.
Definitely beginning to feel like “it is what it is”, which is disappointing. Will continue watching to see what solutions are developed.
Aluminum is strongest at cold temperatures. It is ductile with low density (lots of space between between the molecules). This space shrinks when cold (which is what makes aluminum stronger when cold), but expands when heated up, which makes aluminum much softer and more malleable as it warms up.
Most thermoset plastics retain their strength as they heat up. They do not have a lot of space between the molecules, as they are usually crystalline or semi crystalline, with highly organized molecular structures that are crosslinked. This structure makes them expand in a predictable, strong manner as they heat up. They don’t become weak until they get much closer to their glass transition temperature (which isn’t anywhere near what the bed is heating up to).
In any event, we aren’t talking about the plastic actually “warping” the plate with brute strength. We are talking about expansions of fractions of a mm across the entirety of the plate as it heats up. This is why the surface variations are so small, and why they change at different temperatures.
Some observations I thought I might share here: I know 2 people with Kickstarter X1Cs and none of them is facing a bent bed situation.
However I also know someone who bought their P1P in January (around the same time I did) and they are now getting a bent bed replacement. In fact I see this a lot on FB and Reddit that folks who bought their printers in the last 6 months have this issue relatively more than the Kickstarter guys.
Was there something different about the beds used for the Kickstarter production run? I know that mass produced beds in the last 6-8 months had QC issues as per their own admission, but could there be something actually mechanically different about the current run of beds?
I think all of the beds torn down above are from printers post Kickstarter run.
Slowly built in house, I’d bet. A lot easier to control quality when you’re dealing with low production numbers.
Could also be that third party suppliers were minding their Ps and Qs during Kickstarter phase to ensure they’d get a contract once mass production began.
I doubt anything was mechanically/structurally different, as then Bambu Lab could just revert to that older, superior design. Presumably they have all the bed mesh data and would be able to see which bed versions are “straightest,” no?
That’s exactly what I am planning to do, putting a glass/mirror right on the top of the aluminium plate with the exact same size of the aluminium plate, and than a magnetic sticker also with the same size, I dont care that 5mm of PEI are outside, as I have tested this is not an issue.
But as mentioned I am a bit concern by the heat transfer, what kind of join could be used between aluminium and glass to fill the little air gap in your opinion ? a liquid metal would be the best
I may use special heat pasta.
EDIT: or I will use a thick 1mm/1.5mm sticker between aluminium and glasses that should be able to keep contact/expand a little everywhere even if the plate have a little warp
The first magnet sticker and the steel plate have the size of the heatbed. The mirros has 256x256mm
Now is the mirror removable and I can change the springsteel plate with diff. surfaces
Did someone try to cut the pre-installed magnet sticker with a NT cutter? I ask my self if I should remove it to install my own… I mean, it should be possible to cut it to the right size like the heat bed below without removing it…
I thought I threw it in the trash, but no, so yes I just tried, it is easily cuttable with a cutter.
I have set bed temp to 80°, just remove a corner and pull while retaining the aluminium plate, dont go to fast it is pretty easy but take care to not pull too much the aluminuim, it remove cleanly in one piece, and let a very clean aluminium surface
really, please, if you dont know materials science, please dont comment just for comment… please stop making up storeis but instead listen to what you are told about the rigidy of the plastic frame VS the steel sheet. please
I received my X1C combo this Monday. Printed about 1kg of filament so far and it’s been working quite well with the stock cool plate, glue stick and PLA. In terms of warp I put a ruler across the bed in a few orientations and saw some gaps. I performed a print of a discard chute that took up the majority of the build plate (3 quadrants about) and after it cooled i took the print off and put it on a table and the resulting print had no wobble to it and sat flat. I’m not sure I received a perfectly flat bed but it seems ok so far! Maybe things will change when I print with other filament that does better with a hotter bed
I own a manufacturing company that works primarily with plastics and have done so for almost 20 years.
Feel free to point out what I’ve posted that is a “made up story.”
Is it a steel sheet now? I’m still waiting on my warped bed to arrive so I can do some testing myself, but so far multiple people have stated in this thread that it’s a 3mm thick aluminum sheet.
FYI, I saw someone joke on here about using an old bed to fix a new bed by heating it…
I thought this was a joke, but can confirm that I was able to reduce the “bow” of my bed by 50% or so by doing this.
I took my old, uninstalled bed and put it on the new installed bed upside down. Doing this makes both magnetic sheets attract to each other. I then set it to 110C and let it sit for a few hours. After letting it cool (it takes a WHILE) I then removed the old bed (which takes a lot of force due to the magnets), and rechecked.
I went from a 0.4mm gap to less than 0.2mm gap in the center of my bed. Hopefully it stays fixed for a while.
This isn’t a good way to measure bed flatness, especially if you’re using just a regular ruler (which probably isn’t straight to begin with) and using light from behind to determine the gap. A bright light is going to make gaps appear larger than they actually are.
Gotta use an engineering ruler and feelers or a gauge indicator if you want to know how flat your bed is.
Much more accurate way to determine bed flatness than using your eyes.
Be aware that with so many slice an such thickness, you may have to wait a long time for heat to transfer to the top, and the sensor wich is at the bottom will think too early that the correct temperature have been reached.
As an outside observer I just want to say thank you to everyone on this thread putting pressure on Bambu to resolve this as well as working on 3rd party solutions. I have had an X1C sitting in my cart for a few weeks now and don’t plan on pulling the trigger until there is a reasonable resolution.
