Some Al frames, pre-made are actually about the saem price as the raw material itself due to manuf so many of them. Unless you have a specific design requirement, you might be able to find pre-fab frames for the same cost as the material. I've had solar panels for about 9 years now, and actually just put up an additional panel this year and the frame was the same cost as bulk Al from my local scrap yard! If you'd like my rec on a supplier let me know.
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Go green, use a solar powered light saber...
Contact a local glazier or window replacement contractor. They typically have the best contacts for framing suppliers. The frame for PV panels will be the same for casement style windows.
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"You are, what you do, when it counts" - John Steakley (Armor) 1984
Hi caldwellusa, I suggest you find an old shopsign, where there are tubelights fitted inside. Take the lights out. Insulate the back. Fit the solar panels inside the frame. Buy thin acrylic sheets as "glass". In these financial times it should not be too difficult to find suitable, outdated shopsigns in fairly good condition in the scrapyard.