Complete Guide to Carbon Fiber Foil Board Repairs

Welcome to a new Tech Talk! In this video, we delve into advanced techniques for handling major repairs on carbon foil boards, focusing on instances where significant carbon fiber damage has occurred. Following popular demand, this video is part of an extensive repair series that aims to enable foilers to handle repairs at home, thereby extending the life of their boards and ensuring they remain in top-notch condition.

A list of the essential tools and materials needed to perform this major carbon fiber repair on a foil board:

Tools:

1. Multi-Tool – For removing damaged carbon fiber areas precisely.
2. Sander with Sanding Discs (60, 240, 320, 400 grit) – For smoothing edges and preparing surfaces.
3. Screwdriver or Sharp Tool – To remove soft or damaged foam around the repair area.
4. Spatula – For applying epoxy and glass bubble mixture smoothly.
5. Plastic Sheet or Tape – For covering epoxy and working out air bubbles.

Materials:

1. Epoxy Resin – Strong adhesive to bond and rebuild the damaged area.
2. Glass Bubbles – Added to epoxy to create a thick, smooth mixture that fills gaps effectively.
3. Carbon Fiber Fabric – Cut into small and larger pieces to layer the repair area.
4. Black Pigment (Optional) – To mix with epoxy and blend with the carbon fiber.
5. Clear Matte Spray Paint – For a final protective coat to match the board’s finish.
6. Alcohol – To clean the area before applying the final coat.

Step-by-Step Carbon Foil Board Repair Guide

Step 1: Assess the Damage

Start by examining the damaged area of your board. In this example, we’re dealing with a mini foil board that has sustained severe cracks in the carbon fiber and delamination from the foam core. Gently press around the damaged area to identify any weak spots. Make sure to locate all parts of the board where the carbon is loose, as these need to be removed entirely.

Step 2: Remove Damaged Material

Using an oscillating multi-tool, carefully cut around the damaged area. This tool allows you to control the amount of carbon fiber removed without pulling up excessive material. Aim to remove a square section that encompasses all loose carbon fiber, plus a little extra space for securing the new layer.

Step 3: Prepare the Foam Core

Once the damaged carbon is cleared away, inspect the foam core underneath. If the foam is soft or compromised, use a screwdriver or a similar tool to remove any weak foam, ensuring a solid foundation for the new material. Think of this step like a dentist cleaning out decay; clearing out every compromised area is essential before rebuilding.

Step 4: Fill and Smooth with Epoxy

Next, prepare a thick mixture of epoxy resin and glass bubbles. This will serve as a solid filler in the exposed area. Make sure the mixture is thick enough to prevent dripping. Spread the epoxy mixture with a spatula, filling every corner and creating a smooth base layer. Once it’s applied, leave it overnight to cure completely.

Step 5: Sand and Smooth the Epoxy

Once the epoxy has fully hardened, it’s time to sand it smooth. Start with a 60-grit sanding disc and work carefully around the edges, creating a level surface for the new carbon fiber layers. This step is crucial for achieving a seamless blend between the old and new material.

Step 6: Apply Carbon Fiber Layers

With the epoxy layer prepped, you’re ready to add carbon fiber. First, apply a layer of black-pigmented epoxy over the repair area to blend with the carbon fiber. Then, cut two pieces of carbon fiber fabric—one sized to fit directly over the repair and another larger piece to overlap it. Lay down the smaller piece, followed by the larger one, which will help blend the repair into the board seamlessly.

Step 7: Use Plastic to Eliminate Air Bubbles

Place a plastic sheet over the carbon fiber layers and press down firmly to push out any air bubbles. This step also helps ensure that the epoxy saturates the carbon fiber properly. Working with carbon fiber can be challenging because it’s stiffer than glass fiber, so the plastic helps secure the epoxy evenly over the repair area.

Step 8: First filler coat & Sand and Shape the Repair Area

Once the epoxy has cured, remove the plastic sheet and begin sanding again. This time, use finer grit (starting with 240 and progressing to 320, 400, and even higher) to smooth out the edges. This will create a level, flush surface where the repair merges with the rest of the board. The next step is putting on the first filler coat. Wait 24h and sand it again. In this case we put a second epoxy layer on it to make it even nicer. Wait another 24h and sand it again.

Step 9: Final Touches with Matte Spray Paint

To finish, clean the area with alcohol, then apply a light coat of clear matte spray paint to blend the repair with the original board finish. For an extra smooth result, you can lightly sand with 1500-grit wet sandpaper after the paint dries.

Step 10: Ready for Action!

Your carbon fiber foil board is now reinforced and ready to ride! While you’ll still be able to see the repair due to the nature of carbon fiber, the board is structurally sound, and the added layers make it even stronger than before.

Don’t forget to subscribe, give a thumbs up, and leave a comment if you’d like us to tackle a specific type of repair.

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