SIG Threaded Inserts
Anything that needs to be taken on and off a lot can use these threaded inserts. Especially useful with cowls, wings, and hatches. Machined from tempered brass, these inserts are tough and very simple to install. Nice, clean, machine cut threads that won't wear out, get oil soaked from fuel, and won't vibrate loose. Just drill a pilot hole, add a drop of epoxy or SIG CA Slow on the outside and screw the insert in place with the proper size bolt. When the glue cures, the bolt can be backed out of the insert and it is then ready to use.
Three grooves on the outside of the inserts give full, even cutting action. Since you drive the insert in place with a bolt, the inside threads stay nice and clean. Most of the chips made from insertion are retained on the external grooves of the insert. This aids the adhesion of the glue and makes them hold even tighter. Even in soft wood like balsa.

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