Using riv-nuts - what material

[Brion Toss]

Hi,
Sorry to have been so slow in getting to this. Aluminum rivets would probably be fine for this application, as it sounds like a very low load, and most of that in shear. Just make sure you have rivets sufficiently long for the thickness of the spar. You can find load ratings for both stainless and aluminum versions, so run the numbers and choose accordingly. And by numbers I mean load on line, with the vector figured in, for load on fitting.
Fair leads,
Brion Toss