Weber Ski Synthetic Kinetic Instinct

Aloha Sways,

Had a question on this vintage fin system and the year of this board was shaped. Weber The Ski I believe it’s a guidance fin system. Are there any adapters for this system? It is cracked on a tab or two if I route out old box and put in foam and set a bahne box will devalue the board. I plan to surf it. Any where I can find a guidance fin?

Thank you


I think Huck had a fin box like this on a board lately? He made a fin to fit it.
Huck … paging Huck!!! Strange Fin Box Aisle 4!!!

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Yes I did make a fin for a similar box, not sure if it is the exact same one, there were a few of these “castellated” fin systems at the time 1969ish.

I kept the original box because I wanted to keep the board original, but there is no intrinsic or collectible value to these old midlengths, even tho they are historical boards with a place in the evolution of the modern surfboard. Collectors just aren’t into them unless they are mint condition or have some connection to a famous shaper or event.

And it was a lot of work making the fin.


Thank you,

How does the fin stay locked down with no bolt?

Mine is a Ventral Fin system, probably a little different from yours. But I imagine the concept is the same.

The castellated nubs fit into the slots, and the fin is pushed back about a half inch, which “locks” it in place. It can get knocked out, but the impact would have to come from behind. In forward motion the fin could hit something abd wouldn’t be knocked loose.

To adjust position you take the fin out and re-insert in new location, then slide it back to lock in place.





Your board looks like a pretty cool shape, most the transition era midlengths I’ve seen have been dogs, super humped deck, elf-shoe rocker, and just don’t have the look of a functional board. Mine was a little different, so I bought it at a good price. I’ve restored it (which was a lot of work!) and surfed it once, and it actually rides nice.

I wouldn’t mind selling it to a collector but like I say, most collectors pass over these boards. And if I end up keeping it, I can definitely live with that.

Guidance fin system went out of the market pretty fast since too many people were loosing fins. Were they all impacted from the back? Don’t know. Too bad, since it was the only system without screws, long before FCS II. (Which, incidentally, is also known for lost fins…)