You can easily figure out the springback factor by performing test bends. Springback must be compensated for by adding the springback factor (the number of degrees that a material springs back) to the desired degree of bend. Took the tubing out (it’s not 90 degrees):
The effect is noticed when the material is taken out of the bender. The centerline material is trying to return to its original shape, yet is constrained by the unyielding material on either side.
The cause of springback is uneven density of molecules resulting from stretching and shrinking of a material during a bend. Ever bent a stick of tube, taken it out of the bender, and found it wasn’t the angle you bend to? Relax.
