fcs tabs on wooden fins

i'm in the process of making some hand foiled wooden keels with 3 fcs tabs for a friend.

being keels i'm thinking i need to make the tabs as strong as possible. heres my options:

 

Option 1 - leave tabs in wood template, grind down to slightly less than 6mm thick and lam with keel template with 2 x 6 oz each side. This is the easiest option, but I'm a bit worried that less than 6mm of wood and 4 layers of 6 oz might not be stiff enough.

Option 2 - Leave full timber base along bottom of fins, cut out out tab areas to create mold formwork, route out strip into base of timber. mold bases with milled fibre and resin. drill holes in tabs and in wood template above tabs to provide extra mechanical connection. lam with 2 x 6 oz each side, filling drilled holes. I think this would be stronger, but a lot more fiddly.

Option 3 - Cut timber off at base of fin. drill holes in timber near base for mechanical connection. Form 6mm tabs full length with rovings during lam. cut tabs to size. this is pretty similar to option 2 i guess.

 

Any thoughts on the above options?

I don't know if this is the best solution, or even a good one, but it worked for me

huck, it's a bit hard too see in the picture - is that a continuation of the wood, or are they molded from glass?

either way, how's the stiffness of them when they are in the board?

Thats a continuation of the plywood - glassed over, but not as many layers of glass as the rest of the fin IIRC.  Stiffness is fine. 

I had to go back and file the tabs a little undersized to allow for the thickness of the resin all the way around all surfaces (the narrow edge didn't get glass, but still had to be sealed with resin).

1/8" carbon rod in tabs works great

    Howzit huck,I was going to ask you what kind of wood you are using but then you said plywood which is probably strong enough to do the trick so just make them look like a regular FCS fin and that should work just fine. Aloha,Kokua

Option 3 didn’t really work for me. I would go with number one, this worked for my last set of normal fins.

hi another option which i din/t think i have read about on here is to make fin panels from veneers and layers of glass, , i have off cuts of veneers i use .stack about 10 layers of veneer with glass in between and compress with weights ,
the panels come out really strong ,its really like making your own ply wood but useing glass rather than just glue ,pete

I don't like the idea of having to seal the wood at the base and around the tabs, so I cut off some G-10 and made my base with that. If you give yourself a bit of base, you can glue the wood to it then glass over it for a strong unit. I've done a couple of three tab keels and several double tab twin fin sized fins that have held up well.

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