@gupper_grans nice model would you mind sharing it?
No problem.
But i should warn you, i didn’t have time to test it in IRL. I think, i’ll CNC plate in a week. As a material i plan to use duralumin.
I also tried to design more shim parts, but noticed that back side of heating bed have small recesses. So this must be considered if someone decide to design solid plate. And i think that solid plate will be pretty heavy in metal. Also with such a platform it would take forever to heat up the bed.base plate v.2.stl (2.1 MB)
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thanks for the STL, but i don’t suppose you could give me the original model (so i can easily modify it if need be). also, if you put enough insulation between the plate and heat bed it should not take long at all. i might even try printing this with a high temp plastic (something that prints at like 200) and then put some insulation between it and the bed and see how that works.
Yes, i can share f3d file as well.
https://drive.google.com/drive/folders/1FkO6s_3UsVPbY1tov4sRjTQvLY0nDkJg?usp=sharing
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Anyone make this base plate yet? I was thinking of taking mine down to the machine shop that does my engine work and have him machine the bolt bosses flat.
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I think your right, they would be the best people, I think it is out of spec so should be replaced but as its just a cast they should process it to correct any casting issues, mine is out by 0.4 mm at the rear of the bed but shows up as 1.5mm out on the heated bed. I had it apart today and shimmed it with copper tape so it should now be less than 0.1mm I hope as I used the Snapmaker calibration card. I have raised a support request. I think it may worse on the A350 as its a large bed, is this correct? I think they should machine them in the factory as casting tolerance is out for sure. I have attempted to level mine with copper tape and it has helped. (upload://4ZrRJhHWHEwfUym6TcWupKUndxn.jpeg) 
As an update, my platform was determined to be out of tolerance and a replacement is being shipped.
@tigercjn, yours likely would be too, if you’re interested in reaching out to support.
I think your right, they would be the best people, I think its out of spec so should be replaced but as its just a cast they should process it to correct any casting issues, mine is out by 0.4 mm at the rear of the bed but shows up as 1.5mm out on the heated bed. I had it apart today and shimmed it with copper tape so it should now be less than 0.1mm I hope as I used the Snapmaker calibration card. I have raised a support request. I think it may only be the A350 is this correct?
I don’t imagine they would send me one seeing as how I bought mine from the original backer. He of course didn’t mention the the warp issue but I saw where he buried the print head into it a couple of times. The shimming has allowed me to print @ .1 mm anywhere on the build plate but I still plan on having it machined.
Right now I’m printing an interchangeable dust/fume collector for the heads. then I’m going to laze and cut something to test the functionality of those 2 features.
Once the bed is level and manually calibrated this thing prints very nicely.
It really should have been machined after casting. A couple of swipes at the top and bottom with the stone would have cleaned it right up.
Insofar as I can see, this is a design defect, not just a part tolerance issue. The webbed subbase isn’t very thick and isn’t very stiff. Now affix a heated bed with countersunk screws, which fix the hole positions together between the two planar elements. Heat up the bed and it will expand. Now the top is larger than the bottom, which means the top (heated bed) will become convex (viewed from the top) and the bottom (subbase) will become concave (viewed from the bottom). Even if shimming can get the heated bed as mounted on the subbase flat at some single temperature, but it will move at other temperatures. Shimming a hot bed, what you need if it’s to be flat at temperature, isn’t exactly a great solution.
An additional complication is that the cone-shaped heads on the mounting screws will move the bed by varying amounts depending on how tight they’re screwed down. And that means that you’d want to check and adjust flatness every time the bed is remounted, and even then you have to hope those screws don’t vibrate to a different position during the print.
I also was a backer. As I understand that the warranty is dated from the time you receive it.
I posted the emails I received from Edwin here Bed is not level - #6 by brent113
It sounds like it was machined after casting to a tolerance of 0.15 mm, but mine was over 0.5 mm out as measured by laying it on a table and sliding gauges under the worst corner.
They asked me to return the one I have for investigation.
At least can everyone wait until mine is in the mail before flooding them with replacement requests lmao
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maybe i should take mine into work and have the machinist look at it for me, certainly isnt my strong point but hes got everything he needs, calibrated and ready to go, including a leveled granite surface block.
i can probably figure out pretty easy that its not flat, but he can probably tell me how much and offer suggestions.
must this be webbed as it is? is that for the weight reduction? some true bar or something along those lines would probably be a lot better, but maybe it would be too heavy for the modules?
our surface grinder is far too small 
i could timesave it but the belt is a bit soft and i dont think it would come out very consistently
i was half thinking of making a table out of high temp garolite and press in threaded inserts for composites.
and for the love of god, fine threaded nobs to adjust the height… even at the cost of a few cm of Z height
Mine was never machined. That could be my issue right there.
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The guy that does my stuff says he can get it with .001". Makes sense as a diesel cylinder head is considered out of spec at > .003". I just finished the soundproof enclosure and have a vacuum on the way for dust/fume control so now would be a good time to do it.
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If you’re going to do this, you might as well do the other side, the flats where the two carriage plates in the linear modules mount to.
I am. I will first plane the bottom first and then plane the top so they are parallel. I’m going to take it with me tomorrow
I have a suspicion that the subbase castings were cooled quickly and never annealed and thus have internal stresses from casting. This causes castings to change shape over time. I don’t have a good sense of how quickly they might move. I hope it goes well for you and all the internal stress movement has already happened, if there was any to begin with.
What kind of time frame are we talking about? My serial # is 8, so its been a while. We have a kiln of sorts at work that automatically reaches and holds 1200 F for 12 hours, then remains locked for another 12 until it cools. Do you think that would normalize it?