Comparison of fin box systems
Anyone who has bought a new board and still wants to continue using their old fin will be familiar with the problem. Your own fin never fits the fin box of the board you want to buy. It is not uncommon for the old accessory fin in the cellar to determine the purchase decision for the new board due to its system. This can lead you to ask yourself: Why all this jumble of fins? And which system is best for me now?
The answers to these and other questions can be found here. Five different finbox systems are currently established for windsurf boards. The power box, the tuttle box, the deep tuttle box, the US box and the newest of them all, the slot box. For a long time, patents prevented certain boxes from being used by all manufacturers, but today the brands are free to choose from the box systems. From their point of view, too, a certain degree of standardisation should of course make sense.
Solid and uncomplicated: The Powerbox is the most widespread variant of the finbox systems, in which the fin is simply inserted into the fin box from below and then fixed from above with a screw. Its biggest advantage is that the conical (wedge-shaped) form of the fin head means that the fin is always pulled firmly into the box without wobbling. Minor manufacturing tolerances are thus equalised. The Powerbox is easy to use and offers sufficient stability, even with slightly longer fins.
However, to increase this stability even further, the Tuttle Box and the Deep Tuttle Box offer the option of using two screws instead of one to fix the fin. Both systems do not forgive any tolerances. Due to the straight cheeks, the fin must fit into the box with millimetre precision. The fin is often too thin, too thick, too high or too flat, which means that grinding work is required even with the matching series fins.
Mini Tuttle is often found on quads to fix the small fins. The disadvantage here is that the position of the fins cannot be varied.
The complete comparison of the fin box systems is available as a PDF download.
