DIY Wingfoilboard Repair

Photo: Silvio Hesse

A wingfoil board has to withstand a lot – hard landings, pressure, etc. Most boards are constructed to be robust, but it can still happen that you get a ding – meaning damage to the board. And sometimes you don't even notice it right away.

Dings can often be repaired quite easily and quickly – for example, by simply sanding the area a little, cleaning it thoroughly, and applying fast-drying "session-saver." Such quick repair kits come in various forms. I've had some that have held up really well and for a long time. However, they are generally intended as a temporary solution. It has happened that they have partially detached. Because of where the ding was located, I decided to put in a bit more effort for this repair.

Here’s what happened to me

To this day, I don't know exactly what happened – only when I got home did I see that my board was "crying": water was dripping out. On closer inspection, I discovered two cracks on the underside, large enough that my board had taken on water.

Of course, this had to be repaired. Here's how I got my board back in shape.

The repair steps:

1. Damage analysis

First, I checked the extent of the damage. To make the cracks more visible and accessible, I carefully sanded the area. To avoid accidentally sanding beyond the damaged area, I taped off the surrounding surface with painter's tape – which can be easily removed later.

Safety tip: Always wear a respiratory mask with adequate protection when sanding. Many wingfoil boards are made of epoxy, carbon, and EPS foam – you should not inhale this dust.

2. Preparing the damaged area: Remove loose material

I used a utility knife and sandpaper to remove loose fragments along the crack. This made the hole a bit larger, but I was able to create stable edges – important to prevent further tearing during the next landing. I also removed small loose pieces of the EPS core – luckily there weren't many.

I sanded the area around the hole a bit more, cleaned it thoroughly, and let it dry so that the repair material would bond well with the board.

3. Draining the board

Working on the damaged area also helped to drain the board. I stored it in a room with the heating turned up full. The warmth and the open crack gradually pushed the water out.

⚠️ Attention: Do not simply leave the board in direct sunlight for hours – this can lead to bulges.

I left the board in the warm room with the opening facing downwards for several days until no more water came out. In my case, that was sufficient. Depending on the damage and construction, this process can take significantly longer or require other measures.

4. Reconstruction

To rebuild the area, I used epoxy, filler, and fiberglass fabric. The original construction consists of a bamboo layer, carbon fiber, and epoxy.

As a filling compound and for modeling, I used a mixture of epoxy, hardener, and filler. This worked because the area was not too large. If larger parts of the EPS core were damaged, it would probably be better to glue in an additional piece of EPS foam.

Caution: Do not use adhesive that attacks the EPS, i.e., no solvent-based adhesive. This can corrode the EPS and thus your board core.

I cut out two equally sized pieces from the fiberglass fabric – in the shape of the prepared hole, but minimally larger. I glued the pieces on top of each other with adhesive so they wouldn't slip during insertion.

5. Mix epoxy resin and soak fabric

I prepared two mixtures:

• Epoxy + Hardener + Microballs (Filler): for filling and modeling
  
• Epoxy + Hardener: for soaking the fiberglass fabric

Important: Measure the mixing ratio exactly according to the manufacturer's instructions – I use a precision scale for this. Gloves (e.g., made of vinyl) protect the skin when working with epoxy resin.

In my case, the mixing ratio of epoxy resin and hardener was 2:1. For the filler mixture, I added approx. 4 parts filler to one part resin-hardener mixture until a creamy mass was formed.

Microballs are tiny air-filled spheres. They make the mass light, moldable and prevent the resin from running away. They also make it easier to sand after curing.

Photo: Silvio Hesse

6. Fill and insert fabric

I applied the filler mixture up to the edge of the hole, then gently pressed the epoxy-soaked fabric under the edge, and then added another layer of filler mixture over it.

Everything was covered with plastic film, shaped, and smoothed – then left to cure for 24 hours (depending on the manufacturer).

Photos: Silvio Hesse

7. Sanding and applying a second layer of fabric

After curing, I sanded the area to match the board's shape – slightly below the original level. After cleaning and drying, I applied a second layer of fabric with an epoxy-hardener mixture, smoothed it again with film, and removed any air bubbles.

8. Last epoxy-filler layer and sealing

After curing, I leveled the edges by sanding, cleaned everything again, and applied another layer of epoxy-filler to smooth out small imperfections. Again, I used film and let it cure. 

Then I applied a thin layer of epoxy-hardener over it (without fabric) to seal the small air bubbles in the epoxy-hardener mixture.

9. Fine sanding and finish

After further curing (approx. 24 hours), the fine sanding followed – shaping, smoothing, polishing. I opted not to paint it. The spot now looks a bit like an eye.

Photo: Silvio Hesse

Here's a quick summary:

1. Analyze damage: Has the board taken on water?
2. Remove loose materials: Create a stable edge.
3. Drain if necessary: In a warm room, not in direct sunlight.
4. Supplement EPS if necessary: To restore the board core.
5. Prepare fiberglass fabric: For increased stability.
6. Prepare epoxy mixtures:
   • Epoxy + Hardener + Microballs (Filler): Filling & modeling
   • Epoxy + Hardener: Soaking the fabric
7. Reconstruction: Apply layers.
8. Cover with film: Shape, smooth, and let cure.
9. Sand, clean, dry:
10. Apply second fabric layer: Cover again and let cure.
11. Fine sanding: Adjust shape & smooth.
12. Smooth out imperfections: With filler & sealing.
13. Spray paint if necessary: For optics or UV protection.
14. Hit the water: Test if everything holds up and have fun!

Small Disclaimer: I am not a professional board shaper or boat builder. This article simply documents how I repaired my damaged wingfoil board. The process is based on my own research and on information gathered from various guides, videos, and other sources, which I applied to my specific situation. I cannot guarantee that the same approach will be suitable for other boards or types of damage. Any information provided here is therefore without warranty. That said, after a year and many sessions, the repair on my board is still holding up strong and has proven to be stable and reliable.