JMP's system is a fantastic idea, and I remember when he first reported on trying this. I always thought it was the coolest.
Aluminum, however, is not magnetic, so a metallic whatzit will still have to be attached to the inside of the armor plate itself. Perhaps a large washer would be enough, but only testing will provide answers (also, make sure the washer itself is magnetic
).
Depending on how heavy the armor is, and what gauge aluminum it was made from, there are a number of choices for adhesives. All those mentioned should work perfectly. For my armor attachments, I used bolts passing through the armor entirely, and through grommets in the vest, then screwed the nut from the inside. As the backplate has a hook over the shoulders, and the collar receives little stress, I used industrial strength velcro on these. GOOP was the product I used to attach the velcro to my aluminum armor. Roughing up the inside of the aluminum armor with a rotary tool provided a great surface for my GOOP to stick to. The GOOP has held under some pretty tough circumstances, including several hard falls during a fan film, and shows no sign of failing yet.
