Trying to build a welding bench. Bought a bit of steel, 5mm x 500mm x300 mm, which is big enough for my needs - but it is curved, about 4mm in the center of the long direction, and I need it flat.
Is this curve normal/acceptable? Should I return the steel?
Any idea how to straighten it? I jumped up and down on it, suspended at the ends, without effect.
-- Peter Fairbrother