the dimmensions of the tubing are length=100", width=3", height=7.87", with a thickness of 5/16". i have tried to buy square tubing with these dimmensions but i cannot find any.
i am forming square tubing out of 5/16" mild steel sheets. i can get the basic shape of the tubing but i can not get the tube to close at the top because of springback. i need to calculate the force required to clamp the tube shut to be able to weld the two flanges at the top together, any ideas