Bonding joints

[Aussie 9A]

As a newbe to this forum and with no building experience as yet, trying to absorb all of the information in relation to priming is a bit daunting. It seems to me that any corrosion problems would most likely occur at the joints. If the joints were bonded with a product like sikaflex (polyurethane) to eliminate any cavity for condensation would this suffice as a corrosion reduction strategy? Would this add too much weight? Would the preparation required be less than that for priming? Would the extra strength built into the structure be of any benefit? Would any fatigue problems be reduced?

[Norman CYYJ]

The joints should be primed. Some have tried using a sealant in the joints but the extra major effort is no worthwhile. Some manufactures use sealant on planes that are going to live most of their life as a seaplane but it can cause other problems. If it isn't done properly the rivets don't set tight and in time will work.

[Finley Atherton]

Aussie 9A (Fred),
I see from your profile that you are building a Quick Build. The only major components that you will have to rivet together are the empennage, canopy etc. Most of the priming work has already been done for you in a QB Kit so IMHO you may as well build the remaining components to a similar standard to the QB components ie; fully prime all parts and rivet them together without any extra type of sealant. I have no experience with the wash primer that Vans uses on the QB kits. I used a 2 part epoxy primer and am very happy with the results in terms of weight and apparent corrosion protection. Contact me if you want details of the primer (available locally in Australia) that I used.

Fin 9A (Slow Built)
NSW, Australia.