My life moto is: "Never pass up the opportunity to purchase new tools". The HF shrinker comes to mind. I think you'd do just fine with some formed 0.0409 or 0.050 sheet aluminum in place of the extruded aluminum, and shrinking. Just a thought......
edit: forming said 0.040" aluminum over a piece of MDF shaped for that curve would also work. It will take some effort and time, but can be done by hand.
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Chuck.
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