has anyone found that some fins need a tab/extra area of material that sticks out on the base pointing towards the bottom of the fin for them to sit nicely in the box ? Without them, in some fin boxes, if you continue to tighten the screw the front of the fin actually sinks into the fin box.
MFC for example has this tab and it sits nicely in the chinook fin box. other brand boxes don't always need this tab, and other fins fit perfectly in those. All called US fin boxes.
Anyway, if anyone has seen this, what do they do to a fin that hasn't got this extra tab on the bottom, but needs one.
from my experience I would just put a shim in under the fin, probably a filed down piece of an old fin or something similar.
the fins that come on the starboards has a recessed screw hole, which is pretty good, hides the top of the screw..
Yep - had to tweak a couple of fins by finding a suitably dimensioned piece of scrap plastic and dropping it into the finslot where the 'tab' would be. Building the fin head up with a bit of bog would be a more proper solution I guess, but the shim was easy and quick.
I also countersunk the screw head into the fin head while I was there, so it's all nice and flush. I ditched the piddly little imperial screw and girly little brass nut from my wave board at the same time, and replaced them with grunty (and shiny!) metric stainless ones.
Mmmm... stainless...
I'd have thought that the angles were all wrong for it to rip the screw through the nut, especially since the back of the fin is not solidly held in place, but relies on the screw at the front to locate it.
I can verify that one.
Two week ago i was having a fun wave sail at avalon and i had to delay my bottom turn as a pesky kiter was in the way(instead of sailing out wide over the shoulder like one should) as i layed my rail over to bottom turn my fin hit the reef(24cm select weed wave with brass nut).
I felt a bump and though the worst. The bottom turn turned int a gybe.
As i was able to get on the plane and in the straps i thought all was good.
On getting out the back i flipped the board over and the fin was rocked back only being held in with the pin on the back edge. The bolt and brass plate were gone. there was no damage (to fin or board) and i was able to sail in with no real problems.
