It should be easy to determine the root edge (edge glued to the tube) of the fins as the grain should always be semi-perpendicular to the body tube (it should NEVER be parallel to the tube).
The grain should slope from highest point (in relation to the nose of the rocket) on the root edge to lowest point on the outer most edge from the root.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !