To bend corners at a tight radius, one has to settle for a soft temper which gives you a lower yield strength. The real problem with a soft temper is that set screw frames will dent under the force of the screw allowing slippage of the fittings.
In the old days, we used bends to eliminate competition in a product differentation argument. The same holds true for swaged joints. If you have swaged joints, you have weak alloy. If your pipe is weak, then it requires more of it to do the same function.
Long radius 9" +-bends may be a better alternative. One can also heat treat annealed aluminum material....another subject altogether.
Gary Strome email@example.com
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