ORIGINAL: nitro wing
I apply show finishes to vehicles,no spray can clear can produce a proper gloss clearcoat,none.
At the shop I use clear spray cans,to spot in something under the hood or so,but even the best aerosol product we carry,would never find their way onto my airfame.
You haven't tried the Top Flite stuff it seems.
You should really give it a shot.
This stuff is made for exactly the type of application we are using it for.
It may not look like a car finish, but it's a sight better than applying solutions to just the seams, which itself doesn't really solve the problem, nor addresses the reason for doing all of this.
The buffing with the pad smooths any grittyness or imperfections producing a really nice surface. It's not a high gloss, mirror smooth finish, but it looks VERY good after the buffing.
I've also have had no problems tightening up the covering. Anyone using this stuff is advised to first make sure the covering is tight to begin with. However the Top Flight stuff works fine if you need to reshrink. It stays flexible.
Spot repairs are also not a problem and you can easily re-apply more of the clear coating to make the newly recovered areas look the same.
I've done all of this on many planes as have others here with great success.
I got this tip from someone who also swore by it, and they were right.