Pages Menu
Categories Menu

Posted by on Nov 6, 2019 in Equipment |

Easy Windsurfing Repair | Part 4: Heavy board repair‌

All of the methods presented below could be used to repair anything, from a hole to a missing part of the board! This is because the lamination and shaping techniques mimic the process of making the board in the first place. Therefore, the extent of what you can and can’t repair will mostly depend on your experience and ability.

Ross Williams's catapult during GP Joule World Cup 2013.
Happens to the best of us! Ross Williams’s catapult during GP Joule World Cup 2013.
|PWA World Tour|

Windsurfing in heavy conditions is fun, as it challenges you and pushes your ability to the limit! However, when the wind and waves become a bit too much, you might end up damaging your equipment and yourself. That’s why at Poole Windsurfing we always encourage carefully choosing the conditions you go out in and being realistic with your abilities.

Having said that, heavy damage to your board can happen at any time. All hope is not lost though! In this article, we will cover some heavy duty board repair techniques that can be used to repair even the deepest holes!

Materials:Time required
Core repair:
– High density styrofoam / closed cell foam
– Epoxy resin with slow setting hardener
– Woven fibreglass fabric (200-400 gsm)
– Glass micro-spheres resin filler (optional)
– Sharp knife
– Hack saw
– Sand-paper (80-150)

Tools and PPE:
– Dust mask
– Goggles
– Latex gloves
– Stirring stick and pot for the resin
– Digital scales (down to 0.1g)

– Fumed silica resin filler (optional)
– Sand-paper (250 – 400)
– Colour matched paint

Nice to haves
– Orbiting sander and pads
– Fine rasp
– A lot of patience
Depending on the severity
of the damage from 2 days
up to 1 week.

1. Board repair game-plan!

Depending on the exact location of the hole in your board, the approach to the repair will differ slightly. One of the most common injuries that boards suffer is to the nose as a result of a catapult. Therefore, we will focus on repairing a cracked edge of the nose of the board. However, the key concepts remain the same, whatever the location!

Common board injuries
Locations of the most common board damage: at the nose from catapults and just off the side from the metal harness hook.
|Goya Windsurfing|

Once you locate the damage, it is necessary to determine its extent. If the board is just cracked, but you do not see the core, the board repair just got a lot simpler. In such a case, it will require a lot less prep-work, so you can pretty much skip right away to the last step!

If your board has a big crack in it, and some of the top layer is missing but the foam core is intact, you can skip to the 3rd step. However, if it looks more like the one on the picture above, we will have to focus on repairing the foam core, before using the resin to re-laminate the deck

2. Core prep and repair

First step to performing a full board repair will be to actually damage it a little bit further. Start by cutting out the damaged area in an easy to recreate shape. The idea is to create nice, straight edges, to which we will be able to glue our repair foam core.

The next step will be to prepare our styrofoam slug. To do this, cut off a piece of foam and shape it to closely fill the just created hole. Make the slug 2-3 mm bigger, so that you have to squeeze it into place. Also, make sure to leave enough material sticking out of the board so later you can sand it into shape.

The prepared slug can then be glued into place using a little bit of epoxy resin. Depending on the exact type of resin used, it should cure enough within 4-5h to continue the work.

Afterwards, use a knife or a rasp to cut down the excess styrofoam. Once that’s done, you’re ready for lamination!

3.Lamination prep

Before laminating the surface sand off some of the laminate from around the repair for a smooth transition with a gentle dip. Clean the surface carefully with a wet towel and then use acetone to degrease the surfaces.

The resin we will be using can only be worked with for about 20-30 min. Therefore, it is important to pre-cut the fibreglass mat for the board repair. To match the thickness of your boards outer layer, prepare multiple pieces of fibreglass that can be layered on top of each other.

Lamination guide graphics for use during board repair - buildup of bigger and bigger layers
Fill the pit with multiple layers of fibre matting.

Use sharp scissors to cut the matting, to avoid problems with frayed edges. In addition to making the cutting easier, it will make the layering a much more enjoyable experience.

Resin preparation

After that, it is time to prepare the resin. Firstly, prepare a working area and lay it with painters foil to avoid getting epoxy on anything but the repair. In addition, you can mask off the area around the repair with painters tape, to avoid excess resin sticking where it shouldn’t.

When that’s done, it’s time to mix the resin with the hardener. To do so, place a plastic cup on the scales and measure out a desired amount of resin. As a general guideline, between 100-200g should be enough for most repair.

After that, it is time to add the hardener. The mass will be about 5% of the resin’s weight. However, you should always follow the manufacturers recommended mixing ratio. Once you’ve added the hardener, stir the liquid until both elements are well combined. From here on, you need to act fast!

4. Lamination

Brush on some of the epoxy onto the surface of the repair. After that, place the smallest piece of fibreglass you’ve prepared before onto the resin. Press the piece down into the resin with a hard tool like a knife. Because the mat on its own has no strength, we need it to be soaked through with resin. Continue working the resin into the mat until it becomes translucent. After that, go ahead and apply more resin for the next layer.

When you’ve reached the final layer, make sure to compact the fibres together and get rid of any excess epoxy by squishing the board repair with a squeegee.

Once that step is completed, the fibreglass texture should be proud and visible but not have any white spots. After that, there’s nothing left to do but to let the resin cure over at least 36 hours and put on the finishing touches.

5. The board repair final touches

How much time and effort you want to put into the finishing of the board repair is entirely up to you. However, the bare minimum you will have to do is to cover the repair with a protective layer. That is to avoid the resin being damaged by the UV light from the sun.

The most common factory finishes on windsurfing boards is polyester resin, which gives the surface a nice gloss. Another option (or another layer on top) is epoxy or polyurethane based paints that give the board a little more character.

Heavy board repair (before and after).
Full restoration of the original design.
Which side was it again?’ – Before and after of a heavy board repair by Eva Hollmann

With enough time, effort and skill, you can make your board look just as good as the original! However, figuring that out will vastly depend on the board’s design and styling, so you will have to figure that one out yourself!


Heavy board repairs are definitely not the simplest thing to attempt. The long and difficult process is full of small details that can really screw up your board. Therefore, if you’re unsure of anything and you just broke your carbon based racing beauty from JP, it might be a better idea to get help from a professional repair shop.

If, on the other hand, your board is fairly old, you don’t want to pay top dollar for a repair and you have at least some DIY skills – go ahead and give it a go! Following our guide step by step will get you most of the way through the repair, and you will learn a valuable new skill in the process – even if the board repair itself won’t win any beauty contests!

Share |