Reported by CNC Kitchen, who also attributes it as the reason for adhesion problems on his build plate. Seems to be confirmed by 3D Printing Nerd and Edge of Tech.
CNC Kitchen said the heating element design is similar to the A1:
CNC Kitchen used a thermal camera to identify the cool spot, which he said corresponded to where he was having adhesion problems:
What, if anything, can be done about it?
Curious to see peoples results. I watched Joel Telling’s AMA last night and someone asked a similar question and he said he had poor adhesion and corner warping for PLA on both the textured and smooth plates. Has been working perfectly fine for petg-cf, but that makes sense since petg is quite sticky.
We’ve had no issues with the A1 in our house having adhesion issues. This is a big deal for me since I plan on mostly using the H2D for materials that are prone to warping, so I’m waiting to see how this plays out to help make my purchasing decision.
Maybe with the doors closed it’s better? That’s not ideal that it’s so different in different spots.
Geez, if the heating coil is similar to the A1, all you have to do is look at the shape of the heating coil and you know you’re going to have some large temperature differentials across the build plate. With all the money they spent developing the good additional features in this printer, why did they go cheap on something as important as the bed heating?
glue dont people recommend glue ? to help with adhering , i know bambu do
During the heating phase of the heated bed, the heating power is relatively high, leading to temperature differences across the surface. We are using a high power to ensure the heating happens as quickly as possible.
Areas closer to the heating elements heat up faster, while other regions take longer to reach the target temperature. However, once the set temperature is reached, the heat distribution becomes more uniform.
Based on internal testing, the heated bed stabilizes within approximately 5-6 minutes, which typically aligns with the time needed for print preparation. After stabilization, the temperature difference across the bed is relatively small:
The tests have been done by measuring the surface temperature of the plate, with a thermocouple and thermal grease, to get the most accurate temperature readings.
For high-temperature materials, preheating is recommended to further improve temperature uniformity. Our printing tests indicate that these variations have minimal impact on bed adhesion performance.
While initial temperature differences are expected due to the physics of heating elements and thermal distribution, proper preheating ensures consistent printing conditions.
It should be noted that temperature test results can be influenced by several factors, including:
The above data may vary slightly under different environmental conditions.
Additionally, since the H2D is an enclosed machine, temperature tests conducted in a fully closed state provide a measurement closer to actual printing conditions.
really ? …7 % is “relatively small:” ? …not in my world
The lackluster bed heating on the H2D is the only thing I am disappointed about. The H2D is the first Bambu printer I’ve bought coming from Prusa where we have things like the XL’s dynamic bed heating. I was surprised to see Bambu cheaping out on the H2D’s bed heating—that heating element looks like something you find on a $200 printer, not a $2k one.
As the user above said, 7% delta is pretty significant, especially since we are seeing reviewers having bed adhesion issues already. If I run into any issues I’ll probably just return the H2D…was waiting for the “perfect” 3d printer and the H2D was so close!
At 47:59 mark he talks about thermal deviation of up to 10c
But the video shows it while it is heating, and with the door open. Even with the best conductors, unless you slowed the heating down, there would still be a delta between the heat source, and a place further away. I’d be more interested in seeing a minute or two after preheating.
he had prints fail and had to reprint them, bumping up temp
Having experienced the ‘non flatness’ of the build plate(and after warranty I think 
) after finally needing things to be flat for a single piece on the x1c, albeit a very small degree, I’m most concerned about this geometrical comparison.
The most vulnerable filament seems to be PLA, which can’t rely on the chamber heater to even-out the non-uniformity, without running the risk of clogging.
Cnc Kitchen, 3D Printing Nerd, and Edge of Tech all seem like they’re capable 3D printing enthusiasts yet they are reporting an adhesion problem they haven’t been able to resolve. And now @spinlokd has identified a fourth youtuber above with the same finding. Yet, for obvious reasons, they may be under contract not to say anything that might be seen as too negative. IMHO, we need someone to go in-depth on this and report back as to whether the recommendation of additional heat soak time is enough to solve the problem or whether this is some kind of design flaw that may require hardware modification to correct.
I think the solution to PLA and PETG is a polyura plate (frostbite/supertack). I have 100% reliability with my polyura/frostbite plate with 7000+ hours. Literally not one imperfect first layer yet, and i have not cleaned it either. As a side note i have “textured pei” as the plate type to still heat it, I dont print on it cold.
Oh boy here we go again. The pitchforks are being sharpened and the torches are being lit.
I have seen a view reviews, and the only potential problem should the bed adhesion with the temperature difference with non technical filaments.
But it could also gets to warping with high technical filaments as as one video showed me.
Just that this guy in the video did not say that it could be that problem with the bed heating, just that the warping is there.
It would make sense that the “problem” is the bed heating.
He also compared the print results with the Prusa XL, and that printer had much more warping, but that could have been that the Prusa has no temp controled chamber.
@SupportAssistant
Fact is, if Bambu labs would release an update for a better heated bed, i would want to get that one, because i want a high quality 3d print as an end result.
For those who want, or need high quality end products as 3D prints, this would be important and would spend extra money on that.
Specialy because this H2D printer seems to have about everything else what a perfect printer should be.
All in all i would say, you could give us that updated part, and we throw the money at you to have that better heated bed update.
I am sure i am not alone with that opinion.
Or am i guys?
Not at all. We just need to know the facts, and have confidence in the answers. Bad news never ages well. It’s better to get it all up-front, if there is any, and deal with it head-on than for it to be swept under the carpet, because the truth will come out eventually either way.
I know that in the past, on some other printers, users would add insulation underneath in an effort to improve heated bed temperature uniformity. That seems like a rather crusty solution, especially for such a brand new flagship high-end printer, but whatever can be done might be worth looking at–preferably with Bambu leading the way.
I hadn’t thought of it that way, but this makes sense. Clough42 didn’t have any of these issues in his review and praised the print result for how flat they turned out. All of his prints were technical filaments, so it stands to reason that his results would be glowing compared to those who tested with PLA. Maybe the issue isn’t as big as I originally thought since I don’t plan to use the H2D for PLA.
Good observation. Going from memory, either all or most of Clough42 test filaments were either carbon fiber or glass fiber, which might have also helped by being warp resistant. Probably a warp is what induces the adhesion failure, so he was double protected by virtue of his filament choices.
In the case of CNC Kitchen, the Mandalorean head he printed on H2D had initial adhesion, but on another thread I posted that one of his support trees “disappeared” during the print, probably from a warp induced lack of adhesion: The wait ends on March 25! 🚀 - #961 by NeverDie The result was a deformed chin, because there was no tree to support it. In that particular instance, CNC kitchen glossed over it and made no mention of it, but by playing the youtube back in slow motion we found out what happened.
As you say, a lot of previews seem to have some problems with adhesion, at least we can deduct that if you watch some reviews and focus on the details. Details that are not even adressed within those reviews. It is like playing sherlok holmes and try to find the nasty pin that keeps poking random youtubers.
And that bad “pin” would be the bed heating as the most likely foult that should be corrected.
