AHPC, Fiberfoam, and Hall Spars routinely use pop rivets for fittings on their A-Class carbon masts. The masts are all pre-preg auto claved carbon uni and bi directional materials which might be a better fit for pop rivet attachment. I think they also use a different pop rivet than what you would use for attaching a fitting to an aluminum spar or pole. I believe the pop-rivet body has like a knurled finish for better grip. We also learned you should mix up a batch of West Expoxy (mix it with a little hi density filler) and goop the body of the rivet to add more holding power and to act as an insulator between the rivet and the carbon.

Suggest you call Hall Spars and Rigging in Bristol, RI and ask for their rigging department. I'm sure they would be happy to share their methods with you.

Bob Hodges