comments:
In terms of the extremes, the answer to that question is within a realm of intense debate. However, especially after RocketVlogs recent Supersonic JB Weld rocket series, everyone can pretty much agree that it is not the type of epoxy that really matters. The weakest link is most often surface prep and application technique. This Wildman YouTube tutorial actually goes over some of the surface prepping. One of the most important things to consider is using a filler. Filler thickens and strengthens epoxy making them ideal for fillets. Some epoxies need them, some don't. Just make sure you do your research to make sure if they do. RocketPoxy more or less doesn't exist. Last I remember, it was never officially discontinued, but its manufacturer has no plans of making the stuff anytime soon. The 2-4oz West Systems G/flex would certainly be enough, but I would bet it would be very thin and non-viscous, making it not ideal for something like fillets (one of the most essential parts of building your rocket). You would have to buy filler such as their 406 Colloidal Silica, which would add another $20. Very high quality, but unless you are pushing the limits of your rocket, unnecessary. Off brand fillets may work fine too. Some people swear by West Systems SIX-10 because it is almost perfect for making fillets. However, you would need a standard caulking gun and multiple SIX-10 static mixers (~$5 each). As mentioned before, even JB Weld can get the job done as long as you put in the effort to make it work.