I use a bench vise. There's more than one way, but pulling both out, getting one right with small changes (mentioned above) and matching the other to that.
I have composite stays in my Late Season, aluminum in everything else. (Scouts, Marauder, MollEx, Pointman, 24" Duplex)
I just had an exchange of info from someone who had broken composite stays in a 24" frame. He claimed that the weight difference was "significant". Worrying about breaking stays in a pack frame seems more important than saving an ounce or even several to me. That Late Season is my version of a "light" pack. I've filled the Pointman and MollEx with rocks, and Duplex frames take weirder stresses when I use them, so I would only choose aluminum there.
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