How to insert Longboard / SUP fins
Fin boxes have been used on surfboards for years and are typically found on mid-lengths, longboards and SUPs.
Fin boxes allow a single fin to be moved forward and back, which essentially changes the way the board performs.
How the Screw and Plate Work on a Single Fin
Traditional single fins use a screw and plate to secure the fin into the box. You'll notice a small slot in the centre of the box. This allows the plate and fin to enter the box and lock into the horizontal channel.
Many of the Global Surf Industries boards come with a finger screw and plate like this. These you can just do up with your finger. No tools needed.
Inserting the Plate, Screw and Fin
First, slide the plate into the opening and push it towards the front of the box. Next, slide the back of the fin into the box, ensuring the pin is locked into the channel.
Next, push the front of the fin down, making sure you line up the hole at the front of the fin with the plate and then insert the screw.
If the fin is really tight, you can sand the base slightly with a fine sandpaper or apply a small amount of olive oil to make it slide in easier.
Before tightening, move the fin into the desired position. Moving it forward will allow the board to turn easier and in a tighter radius. Moving it back will lengthen the turning arc and give more control, especially in bigger waves. This is also the preferred position for nose riding.
Finally, tighten the screw to lock the fin in place.
To remove the fin, untighten the screw until the front of the fin can be lifted from the box. Then slide the back of the fin to the middle of the box until the pin exits freely.
Before you install your fins, always ensure your board is on a stable surface.
