Just to make sure I don’t make any mods mad and get deleted, I will answer questions via private message and later on via other channels eg. facebook, reddit.
Happy printing all!
While that looks awesome, those clips are showstopper for me - you will need to take care not to print over them. Prints can go literally to the very edge of the bed.
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I see your fair point. Even with factory settings you can‘t use the full area if you need it because of the clipper mechanism. You can deactivate it by following the official tutorial: Print volume limitations, and how to use the full build volume 256x256x256mm³ | Bambu Lab Wiki
As in the tutorial described you can define „safety zones“ to deactivate certain areas of the print bed.
Best Regards
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I know. I think it might work well for most people, but personally I’ll wait a bit to either be able to get a flat bed from BL or for someone to come up with a magnetic plate that’s flat.
… thinking about it more - how about just sticking a Cool Plate sheet to goodplate? Wouldn’t that work just fine?
I’ll jump in and point out he’s suggesting a solution that retains the plate swap option.
As far as using a Cool plate sticker, sure you can but it would make you use several glasses for different plastics.
This is a great TEMPORARY solution. I am not counting on BambuLabs to come up with anything concrete anytime soon. In fact a plastic print bed mated with a metal heating element, both expanding at different rates during heating, will always be prone to warping.
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Why would anyone make a post stating ‘my bed is flat’? A flat bed is an expectation I would think.
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There is no fast solution for this, as evidenced by the “new” print beds that were sent out that were also warped. A permanent fix will take some time. I’m still confident that they’ll be able to come up with something, considering how amazing the rest of the printer is. Given how much money they raised during their Kickstarter, and how much they’ve made in sales since, they probably have the bankroll to ride out the storm and figure something out. I’m not sure how patient or understanding some customers will be though. Not having a working printer has to be pretty frustrating.
Exactly. Vastly different coefficients of thermal expansion is probably what’s causing this warping to begin with. A glass plate on a metal heating bed would be fine, as both have a similar, low CTE. But the polymer plastic bed is expanding much more than the metal when heated up. This repeated heating and cooling, expanding and contracting is causing tension between the two, which is probably causing warping. There is probably something in the manufacturing process or the testing process of the bed that is causing the initial warping, and it only gets exacerbated once people start printing on them.
I still can’t figure out why my bed (and other’s beds) are still perfectly flat though. Maybe there is enough diffusion between the two materials on some beds, but not others.
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Super easy way to see your bed warp from the x axis. Lower your bed to the bottom and compare to the sheet metal front door opening done by a laser cutter.
Note: look at the BOTTOM of the bed. Not the bed surface.
Looks to be in excess of .010~.020” on each end and most likely the same on the Y.
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Yep. It’s may need a complete redesign of the way the plastic & metal intersect.
I sure hope so, we’re all banking on that with them (pun intentional)
They way they always are. 60% say nothing and watch, 25% are concerned and say so, offering suggestions, 10% are very upset & vocal and sometimes try to help, most of the rest act like Mommy won’t buy them the candy bar and want to burn down the Factory. Lets not trigger that .5% by even mentioning them. 
All are frustrated.
Yeah, I’m sure that has more than a few scratching their heads. Perhaps there’s just a just a tiny bit of variation in the gap between the edge and the metal plate, but that’s just a WAG. A telling clue for the Engineers is that the warp seems to increase after repeated high temp cycles.
Another thought I’ve had is that the plastic parts are being cooled too fast during production. The answer may involve securing the parts between large flat plates and annealing them. That would be expensive on a production line! Big cooling ovens? Wow. $$$
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That’s quite clever and offers a view no one has mentioned! You’re showing off your User name! 
Good spot!
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Submitting on mobile so please excuse any grammatical errors due to my sausage fingers lol
We opened tickets that included videos of tests on both of our warped X1C beds using a straightedge and a light, as well as a clip of the same test on a machine we have from another manufacturer that does have an acceptable bed.
What’s interesting is that while we weren’t asked to run the bed levelling/tramming sequence or to send any data to them, the R&D department stated the bed mesh data “across the board” was within the standard for Bambulab, while also refusing to answer what the range of acceptable flatness was for the beds, and not giving us access to the bed mesh data for either of the beds in question so we could see for ourselves.
Support confirmed that neither a new printer nor a new bed would give flatter results. We were offered full refunds on both our X1CC & with how things are going at the moment we are taking the offer.
Seems to me likely they are doubling down on “nothing is perfectly flat” and have lowered the standard for flatness on their beds
Most people who buy 3D printers are buying them to print out figures and other varying degrees of household kitsch. The beds as bent as they are, are perfectly capable of printing all that stuff. Go to Etsy, that’s literally 90% of the business. A few errant layers here or there, who cares. ITS A DEADPOOL MASK!!!
So, they are actually going to specialize in that market segment and are perfectly okay not catering to folks like us who want a reasonable degree of flatness on the bed. Even if BL was originally capable of delivering that, it seems to be an insurmountable task for them now as they are trying to produce as fast as they can.
Fair enough, here is my suggestion to Bambu, charge more for a more specialized bed, or even a whole printer which is more professional grade than the X1C and I will take you up on that. I am sure others will too. DJI does this with their “Enterprise” variants so why can’t Bambu?
Otherwise if you want greater accuracy at a similar price point, you are better off defaulting to a Voron machine (or a well calibrated Prusa). X1C is NOT the machine for accuracy, and that’s what Bambu is implicitly telling the market by keeping bed leveling data secret.
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Hi, if it can help this is what I’m using since my first post in thread, about 150 hours of printing ago swapping plate in and out as was intended to be. I’m still waiting for the replacement bed. Please note that I’m not responsible for any damage and I’m not going to produce/sell this solution. I do not mind if other people implements/improve/sell it. This is not a final solution. I can say it effectively solves the issue maintaining the convenience of the build plates but may introduce problems (too much mass?). Maybe someone of you can point out and help to find out more.
It’s the case to point out some important things before:
- magnetism - if you put two magnetic sheets (MagSheet) close in the wrong way for long time you may end up with both MagSheets demagnetized. Put it in the correct way and you could have a stronger magnet;
- heat transfer: air or low thermal conductivity material between the bed and your build plate will decrease the temperature on the build plate (loss of efficiency) and slow down warmup of the build plate itself;
- collisions: with this temporary solution your bed will be thicker about 3.5 to 4 mm, consider adjusting the “End G-code” (google for it) otherwise it may cause your bed to have collision with the bottom of the printer. The bed may go all the way down after printing (my printer do that sometimes). Later, when the printer restart you will have a collision during the init procedure.
BOM:
- 1 Glass 257x257 , 2 mm thick (3 mm should work too)
- 1 Magnetic sheet with 3M adhesive that fit the size or a little less (I’ve order one 310x310 that I will cut but at the moment I’m using one for my ender 3 that is only 235x235 - it works
- A glue that resist 120°C…(Loctite 406, you can easily find others adhesive that works even better)
- Few meters of aluminum adhesive tape (about 50 mm width)
- Two simple stops to align the build plates 3Dprinted with a filament that resists high temperature (PATH-CF should be ok and you probably got it with the printer)
- And here the interesting trick… thermal paste. How much? Depend on how bad is warped your bed. I’ve a 45g tube and is almost gone.
Difficult to explain but easy to show and to do it by yourself. Some pictures at the end.
The glass is maintained in its position by:
- magnetic force that occurs between the two MagSheets. If you correctly align the MagSheet your glass will be pushed to the end of the bed (Y direction) and this alone will hold it in place quite well. Very important note: do not glue the MagSheet on top of the glass before understand how the magnetic fields are oriented and how they work. Play with it before, sliding the MagSheet on top of the bed, rotate it by 90° and you will feel how forces works.
- Alu tape at the corners (it should resist up to 120° too), this is necessary otherwise when you remove the build plates everything will come together.
Why the Alu tape under the glass? Because otherwise, when you put a build plate on, the force is strong enough to bend the glass making all this useless. Why alu tape on top of the MagSheet? Just for fine-tuning the surface (I was lazy and not put it under the glass J).
Personally, I think the warping of the bed has nothing to do with different material (plastic/metal) in the original BBL bed. To me the plastic covering the bed has just two functions: thermal insulate the heatbed improving its efficiency (that’s good) and esthetic/design (also good). I can’t believe that in a so beautifully engineered machine someone decide to couple plastic and metal in direct and full (all length) contact. I guess is “only” a manufacturing/QC problem…otherwise, all bed must be warped. But maybe I’m wrong.
In their defense, they are kinda right, especially given how big of temperature changes we’re talking about in such a short period on the print bed itself and in the print chamber. All materials are going to expand and contract when heated up. Rarely is any material going to stay 100% flat, and rarely will it stay 100% flat in these conditions.
Glass heat bed plates, which have an even lower coefficient of thermal expansion than metal, aren’t flat and will flex to whatever the metal plate is below it, so glass will have some variations in it too. Certain metals will flex more than others. It’s just complicated. That’s why printers come with auto bed leveling, to try and make up for the variations in the printing surface that will never be 100% flat.
This is kind of a bummer though. I wish they would be more transparent about these things. I suspect they aren’t releasing it because it’s pretty bad on some of these beds and they know it. Which is why they are probably going to have to redesign the whole bed and start over to prevent such things moving forward.
I don’t think it’s insurmountable. It’s just really hard to scale manufacturing, especially for new companies. I suspect this is why there are some beds that are good and some that aren’t.
I would too. But I think different, upgraded print beds would be a better starting point. I have multiple types of print beds on my production Zortrax M200 Plus. Even though this printer cost 3x more (almost $4k with everything), and even though it has auto bed leveling and calibration, it still requires frequent manual bed calibration to keep it flat. That’s just the nature of 3D printing.
They probably will. But this company is less than a year old and is still getting things right with their flagship product. Give it some time.
I disagree. So far, mine has been ridiculously accurate. I own a small manufacturing firm and we have had some pretty phenomenal results with some specialized tools so far.
I think part of the reason Bambu Lab doesn’t want to release the data is because forums and social media tend to bring out the pitch forks and rile people up when problems like this occur. A small, vocal minority can make things seem way worse than they actually are.
I also think that Bambu Lab doesn’t want to release the data on this stuff because their printer seems to have attracted a lot of users who are new to 3D printing. They might not want to scare off people who will not have issues with small fluctuations in print beds that will never be perfectly flat. Some people might have never had a problem with a bed that is fraction of a mm off in certain spots, but are now demanding new beds because they are seeing others complain about it and want a perfectly flat bed.
That being said, I completely understand that others are not so lucky. Some of these beds are VERY warped. Some look to have very minor variations and are probably fine with the auto bed leveling. What percentage of these machines are bad? I don’t really know. I can only assume it’s still a percentage that’s less than most, or there would be a bunch more upset people posting here if the majority of print beds were bad. It’s the old 80/20 rule. 20% of the people with issues create 80% of the noise. Obviously Bambu Lab needs to get a solution figured out for those that are impacted.
I do know that they’ve at least acknowledged that it’s a problem and they are working on a real solution. And that’s a good start. They obviously have a ways to go to get to a solution.
You very well could be right. I’m only speculating.
To me though, it’s not just a covering. It’s basically the entire bottom in the rear.
That plastic, even if it’s not directly mounted to the bed, is still going to expand and contract when heated and cooled and that’s going to cause tension and stress on the middle of the print bed.
Total agreement. But I think it probably came down to costs. This machine seems to be targeted towards consumers and not pros. A fully machined metal bed would probably fix the problem, but that would be pricey.
I was thinking about this some more today and I think you could be onto something. Different processing on some of the plastic might explain why some beds are good and why some are not. It would also probably explain why it wasn’t caught early on in the design/testing phases, as it’s easy to process in small batches. It’s much more difficult at scale.
The manufacturing firm I own makes custom carbon fiber parts. Carbon fiber has a negative coefficient of thermal expansion. It actually shrinks when heated. The epoxy resin that saturate carbon fiber have a very high CTE, and it wants to expand when heated. So you have two very different materials that are commingling and want to act very differently when heated and cooled. So we have to do something very similar to what you mentioned. We have to post cure them at a very specific rate, while the part is in a mold to maintain its shape. This pushes the glass transition temperature of the epoxy much higher than without post processing. It makes the epoxy much stronger and better suited to handle future increases in heat and temperature swings. We have to ramp up the heat at a very specific interval, keep these parts heated for several days, and then ramp them back down at specific slow interval. It’s an expensive and tedious process, but our parts finished parts will not warp or shrink in high heat situations. Because a lot of my competitors skip this post processing, sometimes their parts will warp and will fail if they are stressed too much from repeated heating and cooling.
Epoxy and plastics have similar characteristics, and the parts I make are technically carbon fiber reinforced plastic (CFRP).
So if I had to guess some more, I think @ThanksForAsking might have keyed in on why some print beds are okay and some are not. As Bambu Lab scaled up, there could be too many variations in the length of time the plastic is in the mold on different runs, how long it’s heated, how it’s cooled, etc. All of these things will have an impact on the plastic and how it interacts with heat when it’s a finished part. Keeping these types of things consistent during manufacturing is pretty difficult, especially when trying to scale. But that’s probably why Bambu Lab has acknowledged that they’re working on a better solution than just sending new beds. I think they know they aren’t going to be able to get consistency with the current design and production processes of their current bed (and probably why they are going ahead and offering refunds to some).
That all being said, obviously I spent a huge chunk of my life working on these sort of things and figuring out the different expansion rates of different materials and how they can coexist in stressful situations. So I might have blinders on and am just focusing on different materials in the heat bed causing warping. My firm is pretty small and we don’t do large scale manufacturing, so I could be completely wrong.
All I know is I hope they figure out a real solution in the near future.
Thats actually the reason why I decided to not fixate the glass permanently on top of the heat bed. The glass lays “loosely” on top of it and is secured with clips. So the glass can expand/retract according its own needs. Yes there will be gap in the middle of glass between hot bed and glass but 2 mm thick glass works pretty well.
My latest ABS print with the glasbed+magnetic foil solution (GoodPlate):
Did you guy touch the plastic parts? They are soft and thin just because they have no fuctional scope (except for what I wrote before and not expose electronic). They are clearly designed to allow expansion and contraction. Please look here: Replace the heat bed signal cable | Bambu Lab Wiki
As it should be. I talked about that a little bit at the beginning of my post. Good glass expands and contracts much less than aluminum and less than steel, but still changes shape at heat.
I saw someone else (maybe in this thread) complaining about those clips and losing some of the printing area, but I don’t think there is a way around this because of the properties of glass. My fully engineered glass plate on a full metal heat bed on my very expensive Zortrax printer is basically the same thing. Glass with 3D printed clips around the edges.
Even thick glass can have issues at high temps. Many years ago I was working with very thick glass (maybe 20mm?) as a mold surface. It worked very well for a while.
One day I wasn’t paying attention to how much heat the glass was getting. It was getting too hot, too fast. Since the carbon was shrinking at heat and in direct contact with the glass, the glass cracked.
That’s also the day I learned that broken thick glass is still very sharp and cut up my hand pretty good.
They might be designed that way, but if not manufactured properly it could still cause problems. Might be that some of the plastic parts are not in spec and are slightly different sizes (bad molds? bad processes?). Could explain why the majority of the beds are okay and some are not.
The plastic on my bed is extremely snug with the rest of the bed at room temp.
Yeah, we need to keep getting this message out. When someone has a problem they often think someone can snap their fingers and POOF! a (fill in the blank fix) pops out. Like Bambu can just call up their supplier and 2 days later things are fine.
Yeah, the more I think about it the more I think it went down like this. When they were a Kickstarter they were running SEVEN HUNDRED machines in a farm. If they had serious bed problems it would have popped up.
They were making the parts themselves, possibly even on their own machines, or in small batches from a co-manufacturer. How the parts were handled and stored before assembly was under their direct control.
After they switched to manufacturing stage they certainly handed that off to some other company.
What if that company is in “cold country” and they don’t keep their factory heated right (not too unlikely in China, workers can be abused). The parts come out of mold and are dumped in cold bins. W-A-R-P.
Another scenario could be when they made small batches there was a long lag between making and assembly. Now that they’re ramped up, the assembly might take place immediately after production before the plastic has had time to “settle” and it settles in place, warping the bed, or it’s assembled in a much different temperature setting.
There’s SO many things that could be going on. People just need to chill while they work out what it is, then convince the manufacturer to change, a whole other can of worms as they’re still small, and may be dealing with a giant that is telling them to bugger off!
Changing manufacturers when you’re trying to launch a business takes a lot of time. There’s momentum in manufacturing and a fix will take time no matter how much Bambu and we users want to wish this away instantly. That’s not gonna happen people. It’s Physics!
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The thing is, they really can just call their suppliers and demand things to be fixed.
Bambu obviously has blueprints for all their parts, doesn’t matter if they’re made in-house or by a 3rd party. The fact that they’re shipping beds like this tells me one of two things, their flatness tolerances are incredibly high/non existant, or they just don’t care about QC unless the customers make a stink about it.
As for part warping due to temperature changes, that can 100% happen, but that’s taken into account when producing the part. Flatness standards apply to parts after they’ve gone through whatever testing they need to go through (thermal shock, chemical exposure, uv exposure,etc). They don’t just apply in the best case scenario. Same thing goes for assembly, tolerance stacking exists for a reason.
Also, when you’re having QC issues with your product, you don’t keep shipping defective parts. You put a stoppage to production/shipments until you can fix whatever is going on.
Before I get called out, I’m not pulling this info out of nowhere, I know this because I work as a manufacturing engineer.
Believe me, if we can produce molded radio trimplates that have a flatness variation of less than 200 microns, which is something that someone driving a car isn’t going to notice, then bambu should 100% be able to produce flatter beds for a prosumer grade 3D printer.
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