2-1 setup / center fin option

General Discussion
1

Is there a standard thruster center fin that I can replace my 9" flex in the box fin setup? This would give me the option to ride my egg as a thruster instead of a single-fin.               Who makes one?

2

FCS does an adaptor im sure. Or, you could find an 80's twinny/thruster. I had a couple and they had thruster sized fins that fit into longboard fin boxes. I still have one and it is pretty handy on my 7'10''. How big is the egg? The 7'10'' surfs WAY differently as a thruster, you lose drive but boy can you crank some turns on it.

3

Rainbow Fins will make any size box fin.

Or the FCS box adaptor if you use FCS fins

4

FCS now sell a M5 fin in the PC composite construction with a fin box base instead of tabs.

I found I needed to shim mine to get a snug fit in the box. Same goes for the adaptor from FCS which is a sloppy fit.

I prefer using the M5 fin as once you put a fin in the FCS adaptor they can be a bitch to get back out again and my first adaptor broke anyway.

Here’s a link to some experimenting with 2+1 set ups on my current egg.

http://community.magicseaweed.com/viewtopic.php?f=13&t=25801&start=120

Just got a new 7" Spitfire style fin to try with DVS sidebites which is my next test.

5

A potential problem may exist depending on how far forward the center box was installed.  I've worked around it be cutting away the rear portion of the base on a 'screw tab forward' style fin and redrilling the pivot pin hole so the fin hangs over the back of the box.  The fin I used was 4 3/4" high and made of solid fiberglass.  It was originally made to fit a standard box slot.

A standard thruster center fin will likely be too small if you have to insert it in a box that is 6" or more from the tail.

6

True Ames makes what they call a “small box fin” from 2.5" to 6" tall made for the typical longboard fin box, and if your box was installed a little forward, they make the same fin in the “1.5” overhang" model, which allows the rear of the fin to slide 1.5" past the back of the box.

I’ve used them in a couple of 2+1 boards when I wanted to ride them thruster - worked fine.