Fin cant on vee bottom

Hey Swaylockers, I am about to install quad fins on a short fish I’ve shaped which has a vee through the tail. I was going to cant the fins approx 7 deg front, 5 deg rear. My question, when a fin cant is nominated, is it based on a flat bottom or straight off the vee (in my case). I’m thinking based on a flat surface. If you apply the 7 deg to the already vee bottom (I use a carpenters bevel), the fin would actually cant significantly more than the intended 7 deg. appreciate the advice Tozza

Let your eyes be your guide.  Forget the numbers, tack the fins on and eye it up till you find what you want.

I would go off the flat.

You can follow the numbers, i think this wise & i generally do, but if it doesn’t look good you’re not going to leave it like that. If it doesn’t look correct, then it’s not! It’s got to be eye sweeeet… Slanj