3D Fins

I'm looking to build a rocket with 3D fins. Styled like an Honest John or a Patriot. What's the best way to build the base frame and how should they be covered? I've seen the PS Patriot which had thick paper over a balsa fin with riser pieces to create the effect. Not sure that will work with mach threshold rockets.

No one has any ideas?

Could you do what the Estes PSII MDRM's do? Plywood with balsa skin to shape... you can fiberglass them for integrity. I have seen this done on a number of Nike builds....

You can do built up fins from a G10 flat center core, G10 spars and ribs as needed for each edge of the facets and cut to shape G10 facets that cover each of the flat areas.

The same can be done with properly sized and glassed aircraft plywood.

Years back I started a 5.5" diameter Viking 7 and sanded all the scale facets into a solid plywood master pattern. Plan was to make a fiberglass mold of the fin and lay up a set of 4 fins with a G10 core that had the TTW tab to the motor mount.

Lots of ways to get heavy duty fins with facets or airfoils.

How big? You could maybe 3D print them. It'd probably be best to print each fin in two pieces, split down the middle, so there's a flat face laying on the printing platform, then glue the halves together.

Otherwise, personally I'd go with either plywood or 3D printed ribs and spars, coverred with heavy paper as a form to glass over.

Here's a built-up method of making Nike-style fins and another way for Aerobee curved fins.