The JD Squared model 32 bender I use does not offer dies for rectangular tubing just square.
What radius are you attempting to bend at? For example the 3/4" square I use for barriers is bent at 3". That is the tightest they offer for the tubing size. Round can be bent tighter, I have a 3/4 round at 2.25" radius. Mine indent both the inner and outer surfaces while the sides remain pretty much as is.
Building one is definitely possible but might be more of a PITA than its worth depending on how much bending you want to do and how accurate it needs to be. I can reproduce things pretty consistently, you may not be able to on a home made unit.
You might be able to get two square dies and stack the tubes to achieve 1x2" It just depends what your trying to do. I've never seen a rectangular bending die but honestly have never looked.
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