I've used this stuff for small fiberglass projects, including my supersonic rocket project (801 mph!) so I know the stuff is reliable and durable. It uses a 1:1 mix ratio, so no counting drops like polyester resin, and no smell. Working time is adequate, 12-24 hour cure time recommended before sanding. Sands very well wet or dry, does not clog up sandpaper It also works very well for filling and finishing balsa, especially nose cones and transitions, Just brush on a heavy coat, optionally apply gentle heat, and the epoxy will soak in enough that when you've sanded it smooth, you'll still have a harder-than-balsa surface that will be harder to damage. Clean brushes with lacquer thinner or rubbing alcohol.