The balsa fins won’t stay on my rocket when I glue them. How can I keep them on?

To keep the fins on until the glue dries:
A. The best glue to use is carpenter’s wood glue. This glue will dry quicker than most other glues.
B. Fin gluing techniques:

1. To create a tight bond, first apply a thin layer of glue to the root edge of the fin and work it gently into the pores and grains of the wood.
2. Repeat this for all the fins.
3. By the time you finish the last fin (1-2 minutes), the first fin has become tacky if not nearly dry. Apply another thin layer to the first fin.
4. Hold the fin’s rear part of the root edge in position on the body tube and with gentle pressure, angle the fin’s root edge up against the body tube until the entire root edge has made contact. Hold the fin in position for 10 seconds. This gradual attachment action acts like a squeegee to force out any trapped air at the connection. Any air pockets not pushed out weaken the joint.
5. Release the fin and you’ll find it secure.
6. It is best to hold the rocket vertically when the fins are drying. Stand the rocket on its nose (without the nose cone in place). Use heavy objects, such as books, to prop the rocket in this position.