For Canada, Robotshop.ca is a distributor of Carbide3D products. I bought two packs of aluminum plate 4 “x5” x0.125 ".
All this is not right, they are crooked. They are curved from the middle so curved on the other side
Is this normal? For me it’s no.
So, as I do not have any pressure to flatten it, and I need full thickness, so no surfacing as a solution.
I am very disappointed with the purchase. And I can not return it since I bought them more than 30 days ago.
If you want something really flat, I’d suggest buying tooling plate.
Do hobby and hardware stores have K&S Engineering displays? Usually they have aluminum plate in similar dimensions — you can sort through them to find something flat enough.
Alternately, make a frame and use a bar and some bolts or clamps to bend it against the curve until it’s flat enough.