Bending square tubing in a JD2 Model 4

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Hey guys, I am working a weird shift this week, so I apologize if I have somehow posted this already. My mind is in a fog.I bent some 1-1/4 square tubing .120" to a 180degree bend on a 4.5CLR. I found it really hard to get the stock out of the die after the bend. I called JD2 and they said it is normal and expected in order to get the tight bend in square without wrinkles in the tubing because they machine the die so perfectly. My question, do you guys get the same sticky stock in square dies? I did oil the dies and the material prior to bending. My only guess is that it was so badly stuck do to some surface millscale rust.
Reply:Many of the dies I've seen for square tube (such as RMD Bender brand) have the upper flange bolted to the die so you can release the part easier after bending.  So, I'd say having the tube stick in a rigid die after bending would be pretty normal...
Reply:I had that same thought in the shower this morning....why didn't they make it in two pieces??? Oh well, the dealer said to use a mallet, so I will go buy one and hang it on the stand. I will now have to make a stand for it. Yeeehaaaw!
Reply:One thing you gotta remember is that the metal has to go somewhere- bending isnt magic.You are shrinking the inner side of the bend, and stretching the outside of the bend. And the metal wants to move in the path of least resistance.So even though you want a nice square tube, perfectly curved and still square, the metal doesnt see it that way. It wants to wrinkle up on the inside, because that is much easier than upsetting and shrinking.It wants to get taller at the outside of the bend, again, cause thats an easier way for the metal to go.So the dies have to hold the metal in, while the metal is trying to get away- hence the pinch.