Estes Mercury Redstone #1921 Build Part 20, Fin Placement

The body tube was roughed up down to the bare tube with 220 grit.

The sides of the fin closest to the root edge were also carefully sanded for better adhesion in the fillet area. Rough up the primer coat just a little bit down the side.
I do this because the fins were shot with primer / filler and sanded smooth before gluing onto the body tube. The primer / filler seals the fin and the glue fillets wouldn't have been very strong.

Even if you were to draw double lines, these fins would be harder to line up than normal. They are thick and the penciled alignment line is covered.

Glue was applied to the root edge.
Looking down from the top, the back end of the fin was set down like a hinge.
Once it was centered down the line, the front end was set down onto the body tube.






Look across the rear to be sure the fins are in line with each other.