In the interest of celebrating the fact that it's not 120 degrees in my garage anymore, I decided to make a tubing bender for 1/2" square steel tubing. The bending die is a 6" diameter X 1" steel disk with a 0.475" x0.550" notch in the outer edge. It works and bends smoothly without kinking the tubing, but it is very difficult to get the bent tube out of the die. The walls of the die are about 30 - 50 mils larger than the tube outer dimensions and they are vertical. They are also not the most beautiful finish.
Should tube bending dies have straight walls or should there be some "draft"?
Should I allow more clearance in the die or will the tube just expand out to fill it or kink?
Should I work on the finish of the inside walls of the die?
Are square tubing benders generally a pain to get the bent tube our of?
Thanks in advance, Bob