The Bob Smith epoxy is good for general use but it can be runny. It's like honey, you put it in one spot then in a few minutes it seems to be everywhere. I've made fillets with it by turning the rocket on its side and slowly pouring on a little bit along the fin root. It gradually self levels so your fillet is not curved, it's triangular. I put a piece of tape on at each end of the fin root to form a dam to keep the epoxy from running off the ends of the fin root onto my table. After it has cured I take the tape off and sand the edges smooth.
RocketPoxy G5000 is excellent for fin fillets. My Estes Mean Machine crashed, and the only thing on the body tub that wasn't destroyed was the fin fillets.
I like Rocketpoxy for fillets where you have already done internal fillets with something else. It doesn't soak into the materials so I wouldn't use if I'm doing external fillets only. BSI is good stuff but I like to stick with the 30 min. formula as I feel the quicker drying epoxies don't have time to soak into the materials. When using BSI I like to heat the materials and let the epoxies soak in hot water for a few minutes as it flows and creeps better when warm.
I was just thinking since I have noticed when some rockets are on the pad baking in the sun waiting to be launched, there have been observed instances that some epoxies become a little pliable and fins may wobbles or just come off. Thank you for the reply though. Much appreciated 🙂👍🚀🪂
