How to Repair Fiberglass on a Yacht – What You Need To Know


Repairing fiberglass may seem difficult – but with the right tips and advice, just about anyone can do basic DIY fiberglass repairs. Repairing minor scratches and dents is pretty simple – and with the right tools, you can even take on minor hull breaches and holes, and other yacht hull restoration tasks. Here’s a quick guide to fiberglass repair from Chi Yacht Refinishing!


Minor Surface Scratches

Surface scratches can be caused by weathering and damage from docking, as well as a variety of other issues. Luckily for you, repairing scratches in your fiberglass is quick and easy – and just about anyone can do it!

Start by buffing the area around the scratch with a low-grit buffing wheel or sander, to remove any fiberglass that may be erupting from the scratch. After you have smoothed the scratch down, you can use gelcoat, epoxy, or resin to fill it in. Fill the scratch with the proper product, and ensure that you use enough to coat the entire area. Then, sand the area down once more to ensure that the fiberglass repair is flush with the rest of the boat. Switch to a polishing wheel and use buffing compound to bring out the gloss and finish of the fiberglass – and you’re done! Just don’t forget to wax your boat or re-apply your ceramic coating before you get back out on the water!


Small Dents And Patches

Deeper dents and damaged fiberglass patches are usually repaired using fiberglass “chop”. Chop is powdered fiberglass that is mixed with a filler to create a putty-like fiberglass substance that can be used to fill in larger holes, and smooth out rough patches.

Sand down the affected area, as before, and then mix the “chop”, filler, and gelcoat for your boat in a small container. You will have to apply it quickly – you only have 10-20 minutes until it sets.

Apply the substance to your dent or patch, ensuring that it’s “mounded” slightly above the hull. Let it set – this usually takes 1-2 hours, depending on humidity levels, but you can leave it for up to a full day.

Once the dent has cured, use your buffing wheel and a low-grit compound to remove excess filler material, then go over the patch with a high-grit polishing wheel to restore its shine, and complete the repair.


Hull Breaches

Hull breaches must be repaired with a combination of fiberglass mat and cloth, resin, and gelcoat. In general, we recommend against DIY hull breach repair, as a poor job can compromise the safety of your boat.

However, the process is still quite simple. You begin by cutting damaged material away from your boat’s hull. Then, you will dewax the area with a standard solvent, to ensure no wax is present during the repair.

After this, you will have to bevel the edges of the fiberglass repair using a disk sander. Next, you’ll apply paste wax to the exterior of the damage, and screw in a Formica or Plexiglas plate to ensure the interior repair adheres to the correct curve.

Finally, you will apply strips of fiberglass mat and cloth to the exterior of your hull, bonding them into place with resin, and applying a catalyst to bond them into place permanently.

You will repeat the process on the exterior of the boat using one layer of fiberglass mat and cloth, then apply gelcoat to the finished fiberglass repair. After it dries, sand and polish the area to bring it back to a beautiful shine and luster.


Need Professional Yacht Repair Services? Come To Chi Yacht Refinishing!

DIY yacht restoration is never easy. If you’re not sure that you can handle the project, or you have a large hull breach that requires attention, contact Chi Yacht Refinishing right away.

We’ve got a huge team of skilled yacht repair specialists – and we can handle jobs of any size. Read more about our services now, and schedule your appointment today.