Adaptable Surfboard System for Prone Adaptive Surfing

This Jabali 5'4" wooden surfboard has been retrofitted with US fin boxes on the deck, allowing prone adaptive surfers to add and personalize various attachments. This setup makes it easier to test and use different attachment configurations.

This thread is specifically about how the fin boxes are integrated into the board. The making process of the attachments is available on my profile.

This project was part of research on adaptive surfing conducted at the University of Ghent as part of my Master's thesis. If you have any questions, feel free to contact me at charlie.debreuck@gmail.com.

supplies needed:

1. Surfboard
2. 7 US Fin boxes ( less is possible depending on the need of the surfer)
3. Adhesive (suitable for ocean environment)
4. Epoxy (preferably Biobased)
5. Varnish

Guidelines for Fin Box Placement

The surfer's body position while lying on the board is used as the main reference.

1. Top fin boxes (handles): The centre of the fin box should be aligned with shoulder height and angled inward.
2. Middle fin boxes (chest riser/handles): These should align with the torso area.
3. Bottom fin boxes (leg guards): These should be positioned at calf height, near the rails. The leg guard should not come into contact with hard/bony areas such as the knees or feet.
4. Fin placement: The fin box should be located at groin height, closer to the surfer's centre of gravity.

Tip:

After determining the desired positions, check the symmetry of the layout by measuring from the stringer as a central reference. Finally, mark the placement of each fin box with masking tape.

Route the marked holes for the fin boxes with a suitable router and router bit depending on the chosen boxes.

Depending on the type of board (here a hollow core wooden surfboard laminated with epoxy and fibreglass), the fin boxes are glued in using ocean-resistant adhesive and secured with clamps. They are then left to cure for the duration recommended by the manufacturer.

The protruding edges of the fin boxes are sanded flush with the deck using 180-grit sandpaper and rasps. To prevent damage to the deck, masking tape is applied around the fin boxes before sanding.

The board is waterproofed by filling the gaps with an epoxy resin suitable for ocean environments. After the resin has fully cured, the board is sanded down again to make it level with the deck—first using 180-grit sandpaper, followed by 400-grit for a smoother finish.

To finish the board, three layers of varnish are applied, then wet-sanded down to a smooth, clear finish using 1000-grit sandpaper.