What amount of force is needed to bend metal?

Depends on what metal you are refering to. * Aluminum is can be bent at 1 ton * Stainless at 50 ton * Mild Steel at 100 tons * Carbon Steel can be bent at 150 tons. All of these metal depend on the thickness of the material. For example, the thickness of these metal would have to be between the thickness of .25 (quarter inch) to .50 (half inch). Note: It also depends of the quality of the metal. SS 1311-00 steel (Swedish standard), for example, can handle 220N per square millimetre until it reaches its yield point. Once the yield point is passed some fraction of the deformation will be permanent and non-reversible. Answer: Mathematically

Δ = PL3/(48EI) Where: Δ = deflection

L = span

E = Modulus of Elasticity (see link for typicals)

I = Moment of Inertia

b = width

d = depth

I = bd3/12 for a rectangular cross section