fins fixation

it's my first fiber glass rocket and i'm searching about the best way to fix the fins to the rocket air frame
can anyone help me please ?

Fix: b. To spay or castrate (an animal).

Oh. You mean "attach" or "bond", sort of the opposite of "fix" definition #2.

A few things need to be known to give the best answer. Is this a fiberglass kit and what does it's maker suggest? Home brew? Size? Power? Thru-the-wall (ttw)mount? Surface Mount? Fin thickness and height relative to root chord? Trailing edge straight, swept back or swept forward?

I am about to hack a 2.6" FG ttw kit with 3/32" thick split fins into a minimum diameter that will go about 1.5 mach. It already has fin slots but I will be re-purposing the centering rings and motor mount. I will be mounting the fins in the slot flush with the bottom of the slot. Large external fillet, then tip-to-tip (t2t) carbon clothe. The t2t is probably over-kill for < 2 mach, but the motor case is heavy and t2t gives it some bounce margin.

You will need to consider how life is going to treat the joint and design appropriately. Or follow the manufactures directions. Or read the sticky thread on building a 3" Dark Star.

But the most fun will be to answer some of the questions above and get us minions arguing over the best method.

Most HPR rockets use epoxy for general bonding of materials and that's most likely what you will use. (Mechanical fasteners are possible, but unusual for this purpose).

I have an introductory video on epoxy usage that you may find interesting.

Also, this video on building a level-1 rocket has a lot of techniques that are important to know.

Excellent videos John, thank you for putting in the time and effort, and, for sharing them with the rocketry community.

David