They replaced the power connector on the board to a much more sturdy design.
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Even the aluminum PCB on my original one was/is warped and the warp on my new one is very smooth across itâs surface, even with the spring plate removed. However you have a good point. Looking at the construction, the magnet layer is applied to both the aluminum PCB and the plastic frame. I just checked my old bed and there is definitely some variation is height between the two around the edge. Either shim the PCB always be proud of the plastic frame, or trim the magnet sheet back to the size of the PCB. Youâd lose 5-6mm in each direction but I donât know that would be any worse than the outer 2-3mm of the magnet not being adhered to the plastic frame.
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The Prusa Mk3 bed is only a PCB, no aluminum, no magnet layer (magnets are in the underside of the PCB). no PEI layer. Just a 2.5mm PCB, with the copper layer on top and a heavy solder mask over that. It has a 5mm aluminum frame that is attached to, with stand-offs between them. The key difference is that it has a support point dead center in the bed, and eight around the outer edges, so you can actually adjust the bed to be, and stay flat. Itâs actually the aluminum frame that maintains the overall flatness and being separated from the heater, it doesnât undergo nearly the thermal stress as the bed itself. Itâs not zero obviously as you can get 40-50C ambient if you are printing high temp materials in an enclosure, but you level at operating temp and donât worry about what itâs like cold. Obviously doesnât work as well if you are printing both super high and super low temp materials, but thatâs why we have multiple printers, right?
I continue to measure my new bed. Y axis with PETG is about 0.09mm and itâs not quite so smooth a curve. It looks more like the adhesion was light in some areas. It does have any overall bow to it, this time the middle is high rather than low. However its at a level that if had this across both X and Y, Iâd consider the printer usable for large scale prints. Not great, but usable. Running a Y axis PLA print now.
Yeah, i am trying to level this second bed i got as it was not âperfectâ either. By hand bending it i am pretty close, thinking i better leave it like this before it breaks or something! I have to put pretty much pressure to get some movement of the aluminium plate and i know there is a fine line here where it may bend to much. This bed was only warped in one direction, and fully flat in the other. But bending it back it showed a slight waviness of maybe 0.1-0.2mm i guess by eyesight.
On this bed i also shimed the plastic frame down so it is fully aligned with the metal plate.
I will need to find a magnetic bed, i have ordered one already.
and yes, i use a prusa satin sheet for my printer as the satin sheet is just the BEST ever print surface 
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This is the only magnet sticker I found with proper size and high maximum temperature. https://www.aliexpress.com/item/33015063641.html Although itâs 1.2 mm thick instead of original 1.8mm. Maybe itâs even good as I intend to try adding 1mm thick aluminum plate on top of the heater plate to get rid of magnetic surface edges being attached to plastic. Donât know how good it actually is but I ordered it and it will likely arrive in about 2 weeks.
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Cool! Many thanks for the link! I could only find a 250x250mm sticker here locally so waiting for that one, but this one looks nice! (i also asked bambu if i can buy a new sticker, lets see). I actully think the thinner the sticker the better. After all a polymer is a polymer, not easy to keep flat. I am even considering to skip the magnetic sheet by putting magnets below, but lets seeâŠ
Otherwise there are many selling sheets for creality or similar that are the size of 310mm and the magnetic sheet is easy to cut soâŠ
I dont forsee really that the thickness should matter. The only thing would be maybe if in some strange way, the calibration pattern for the camera at the side of the bed is that distance dependent, but dont know?!
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Higher thickness provides stronger magnetic force given that everything else is equal.
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Haaa ok ! thanks for all those précisions, I think it was mentioned as a comparaison because It was similary made 
but anyway thatâs still quite impressive, even when I use mirror wich are considered pretty flat, I often found 0.1 or 0.2 mm diffĂ©rences
I bought this pei flex plate for my CR10S. Itâs magnet sheet is 1.70mm thick. If your interested in buying a magnetic sheet.
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Please let us know if this is possible. I would then also replace my sticker, so that I am also immediately rid of the air bubbles.
Could you explain a bit more please, with picture maybe ?
Isnât is possible to cut a little the magnetic layer (5mm?) rather than the plastic ?
yes possible to cut i guess the edge of magnet.
when the bed is new and never heated it is easy ti remove magnetic bed sticker and reuse it. but after heating it gets stuck very hard so brakes when removing it
still, the bed is often bendend. so one need to remove sticker, dissambley the bed and straight it. shims out the plasitc edge below the bed screws, then put all together
Ok thanks, I am not sure yet that I want to dig into this fully, I got a X warp that I am petty sure come from what you said about plastic border, Y axis seems perfect. I dont really care about a little warping as long as it is not on a too short distance (wich is the case on X borders)
I probably wont unbend the aluminium as it appear to me that it is too much work, I was just thinking of cutting and remove 5mm of magnet from the left and from the right of the bed right in place, do you see any downside, something under that could be damaged ?
Also I have read from Bambulab Wiki :
The X1 series printers on the market are equipped with both V2 and V3 heatbed, and they will all be transitioned to V3 heatbed in the near future.
So maybe better to wait for a V3 bed before unmounting everything
yeah, there is some work for sure!
maybe there is changes the plastic moulding of the v3. i mean it is obviously is changes to th mold as the connector is different and that is a tool change during manufacturing.
i would never dear to do this if i did not get a replacement bed from bambu which was very nice of them as my initial is very warped. but instead of complaining that the bed is not 100% (i do belive it is good enough for 80% of people out there as the auto bed leveling is amazing) i chose this path.
With that said, amazing printer still! looking forward for the uppgrade in a year or two. This is their first printer and still super!
for me the speed (i dont run max max neither) is the most important upgrade from my old prusa. For prototyping as i use it for, to be able to do a few iterations in a day/evening is amazing. i push out sometimes 2-3 times the speed of my prusa and that is amazing. I was looking for the voron route but deemed this âbetterâ and cheaper. The speed is not comming from âthe electronicâ but from the hardware. It is amazing to see the carbon gantry etc. As a material science/mechanical engineer this is a little marvel for a mass production unit and it beeing the first iteration!
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Heating the bed to 80°C make the magnetic layer easily removable, so I think I will just cut the 5mm border for now and see how it goes.
Then I will wait for a V3 bed and the new auto-bedlevelling wich will include borders on future Bambu Studio, afterall I care about this only because of this thread, I have printed hundreds of parts without issue
Yep fully agree, I print a lot more since I got this printer, as it enable me too, to iterate very fast on prototyping
Heat does not make it easily removable, it crumbles instead. And your picture only proves that.
the crumble is not as bad when you put it back so not an issue.
But even if my magnetic bed lifted on the sides it did break when i got closer to the middle.
lets see for v3 what it can do
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Well I just need 5mm, that should be ok, thanks for your kind advices 
While adhesive may hold it somewhat stronger, this magnetic rubber is quite strong when cold and can be removed unbroken. Heating on other hand guarantees it will crumble.
EDIT: also as I said previously. there are two recesses in the frame where you can insert some sort of spudger underneath the magnetic rubber as it just hangs over the air and start prying with minimal damage.
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O â â â â .
I was told several weeks ago my replacement bed will ship end of April.
That I did not mind as I thought they would have this issue sorted by then.
Just had tracking for replacement.
Hope it will be useable.
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