Hi all. I have a 7’10 fun shape that has a FCS 1 thruster setup. Is there a larger dual tab fin that I can use to ride the board as a 2 + 1 or as single fin? OR is there some kind of adapter I can use to put in a box fin? Thank you for your guidance.
In my opinion the rear plugs of a thruster cluster will be too far back for a 2+1 centerfin. I hate thrusters on midsized boards to begin with so I’d pull those plugs out and replace with a longboard finbox. That is, assuming your board is thick enough at 5" forward of the tailblock to support a finbox.
Yes replace the center plugs with a longboard box. The box will cover the plugs and leave you enough forward distance to set a center fin at five inches. FCS makes an adapter that will allow you to go back to a Thruster set up if desired. The position of the forward fins is also a problem should you install a center box. They will not be forward enough to ride as a 2 plus one. The result will be a “Cluster” of fins, all too close together to function as a 2 plus one should. You would have to install more plugs for the side fins to move them forward to 16, 16 1/2 or 17". Better just to shape yourself a new board with the desired fin configuration.
If you wanted to try a different fin setup then maybe a twin+nubster or twin+sharktooth would work better for you on a 7-10 than a thruster. This will move the center of effort for the cluster way further forward than is the case for a thruster. Then the only thing you’d need to sweat is whether the plug install on this board was good enough to support the side loading of a twin fin + 7-10 length.