The springs have a certain number of turns they must be adjusted to. I had this as a business as a kid, forgot the #. Call a door shop they will tell you. It takes two 1/2 diameter rods about a foot in length, insert them into the spring mount holes. Rotate in 1/4 turns, have a small crescent wrench hadn't to tighten little square head bolt to the shaft to lock it down. Be careful, let go at the wrong time and it can hurt you. Make sure equal turns on both sides.