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Hello All,
I hope this is the correct area for this question, I searched but found nothing that addresses this issue. I am to the point in my build in which I am squaring the bed to the towers. When I lay a straight edge across the bed it's higher in the middle, looks to be around 1/32-1/64th lower on the outer edges. I have loosened my screws and then checked, still the same. Any recommendations? I've made sure that I'm not on the kapton tape and I'm using a dead flat straight edge.

I don't know if the onyx bed is meant to be truly flat. The glass is what's important. Obviously surface contact suffers a little, but it's unavoidable I believe.

Some others have said that if you loosen the screws and press down on the bed with a known flat object (like a level) as you tighten the screws, it will take some of this out. Bot is right though, the boro glass build plate is the stronger, flatter surface that should hold everything together.

Ok, so I should just be sure that the square contacts the onyx plate in the middle even if it doesn't on the sides?

I don't know, I didn't square anything to the Onyx bed... If I were to square the towers it would be to the glass surface on the onyx bed. I don't know what the new manual says, though.