I think you've got the most experience of all hobbyists. I'm very happy with my tri-fin conversion of the K 11.5....in some of the pre-conversion banter on the Boards UK site, some had expressed reluctance but I ended up quite satisfied.

PS - it looks like you're developing a neck problem... 

Last edited by Geoff (2012-02-15 12:50:08)

;-)

Looking good - love to see the final result and hear about how it performs....
This is the Exocet - right?
Why did you decide to make it a quad ?

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boxes fitted ( not glued , with Black Project Fins

those are 13 & 15cm, hope to get a real quad feel with fins close to the same size. BPF do not have a lot of area for length, I really like the performance of them.

Sail..  5.5 SF  6.3 SFUL  and  ideal  ..umm Fire Light 5.7.

as far as fins go.. I have  13/15  ..10/16 ..  11.5/12.25 .. 8/15

and a pair of 17s

fighting weight right now 154lb

Cobra

Having seen how they are made now, I would consider making them myself. Using pour foam as the outer shell, with carbon reinforcement on the corners, the slot itself would be a test to get right /achieve,  probably  would have to use some dummy fin head to size and then extract, I think the installation is strong enough, but not overly sold on the slot box ..yet.

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How do you align the cant of the fin boxes? The ProBox setup is made to do this, but I'm curious how you do it here...

I was meaning cant, not toe-in, which I find fairly straight-forward. I figured you must make some kind of jig or support while the epoxy sets. Do you put a fin in the boxes to set your level? Or is that what the blocks are in the photo? I would assume you use the existing center fin as the reference, since the bottom isn't flat nor perpendicular? Seems pretty tricky!

ProBox are really quite easy, I agree. Except that I insist on mounting them in Divinicell, which adds a round of complexity because you have to rout out the foam, imbed the Divinicell in the foam, and then glass it over before starting the ProBox installation. Still, it's not bad.

Pour Foam is a good solution, easier than Divinicell and still closed cell, but I didn't go with Pour Foam because it's not as strong. To me, the main issue with fin boxes is creating a closed-cell barrier to prevent water getting into the board if the fin is dinged a bit hard in the shallows.

I seriously thought about using Pour Foam, because I've got a 2 quarts or so of the stuff (a quart of each part) - enough to fill up the whole house with foam! I'll never use it all, but it's the smallest quantity I could find at the local marinas. Still, I went with Divinicell. Boardlady likes Divinicell for this purpose, but for little side-biter fins or a tri-fin, I'm not sure she'd insist on Divinicell. In normal sailing, there's not a lot of load on these dinky-small fins.

its done now.

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some nice slotboxes...

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about 100 gram each. strong!!

mounted in these boards ;-))
V      V      V
http://hot-trips.blogspot.com/2012/03/m … oards.html
a special collab :-))

Last edited by david (2012-03-18 11:18:14)

yup, boxes are flikka home mades. really really solid. Due to the big hard pvc foam easy to
mount. You can order them at Flikka. (use these magic discount word: Mons... , maybe it works;-)
available in 2 sizes.
I got those boxes also @home.. cause many board projects in my head.