How to gel coat a boat? Some top tips for gel-coating your boat

Do you know how to gel coat a boat easily? Gel-coating a boat is an important step in maintaining the look and feel of your vessel over its lifetime. For most people, gel-coating their boats can be intimidating and time-consuming. With the right materials and techniques, though, you’ll be able to coat your boat with ease while also becoming more confident in your handiwork!
How to gel coat a boat? Some top tips for gel-coating your boat

How to gel coat a boat? Some top tips for gel-coating your boat

 In this blog post, Scott Ewart walks you through how to apply gelcoat to a boat. Besides, we also give you some top tips for gel-coating your boat to get the perfect finish. Read on for everything you need to know about this topic!

How to gel coat a boat? 14 easy steps for gel coat process

Step 1: Prepare all tools for gel coat

Step 1: Prepare all tools for gel coat

Step 1: Prepare all tools for gel coat

All gel-coat tools includes:

  • Pressure Washer
  • Masking Tap
  • Sandpaper
  • Paintbrushes or sponges
  • Acetone
  • Orbital sander
  • Oxygenated Solvent
  • Resin/Hardener Mix
  • Plastic film or wax paper
  • Roller or brush hair
  • Buffer
  • Soft cloth
  • Spray or liquid gel coat (clear or colored)
  • Gelcoat Coloring Pigment (optional)

Step 2: Watch weather before gel coat your boat

It is important to pay attention to the weather conditions before you start gel coating. Make sure there are no storms in the forecast and that temperatures of at least 75 degrees Fahrenheit with low humidity. This condition can be expected during application and curing time.

Step 3: Prepare the work area

Avoid toiling in the direct rays of the sun. Select a location that’s in the shade or on a cloudy day for optimal results. Accelerate your material’s drying process to save time and effort during your work.

Before you start the gel coat application process, make sure to clear the area of any debris. This will help ensure that your boat’s surface is free from dirt and dust particles, which can interfere with the adhesive properties of the gel coat.

Step 4: Prepare and inspect the boat’s surface

Prepare and inspect the boat's surface

Prepare and inspect the boat’s surface

Clear the boat surface

To ensure a successful bond between old and new gel coat layers, it is important to thoroughly clean the boat’s surface before beginning. Remove any dirt, grease, or oil deposits with a solvent, and use emery paper or steel wool to sand away any old or flaking layers of gel coat.

Check out any damage on the boat

Use painter’s tape or masking tape to mark any cracks, scratches, chips, or other damage. Simultaneously, make sure you shield and guard areas of the boat that will not be serviced.

A masking tape comprising a strip of flexible material narrow in width and having adhesive material on both sides


Step 5: Sand the damaged area of the boat

Use an orbital sander with 80 to 120 grit sandpaper. Make sure to sand the area evenly, avoiding deep scratches in the gel coat surface. This will help create a good foundation for the repair material. Wipe away any dust created from sanding with a clean cloth or rag. This will ensure that no dust or dirt particles remain on the surface of the boat.

Step 6: Fill the boat’s holes and cracks

Fill the boat's holes and cracks

Fill the boat’s holes and cracks

This step will depend on the size and depth of the holes or cracks. For smaller defects, a gel coat paste or putty can work well. Heavier damage may require additional materials such as fiberglass repair kits or epoxy resins.

  1. To rid the area of residue, begin by wiping it down with acetone.
  2. Create a thick paste of gelcoat in the appropriate color and then use a trowel to gently apply it to the area in question.
  3. To prepare the area of repair, scrape away any excess material and flatten the surface. If there are deep cracks that need to be filled, combine fiberglass filler with a hardener before applying gel coat paste for a final finish.

Note: To prevent any dirt or debris from infiltrating the repair, lay a sheet of plastic wrap or wax paper over it.

Step 7: Sand the whole boat’s surface

Sanding while wet is recommended for optimal results, to dampen the surface.

Use a spray bottle filled with water and a few drops of dish soap.

The quickest way to clean your sander is to dunk it in a pail of water. But if you do that, the water will leave behind residue that might mess up your paint work.

Step 8: Mix the gel coat

Mix the gel coat

Mix the gel coat

Generally, you can cover between 40 and 80 square feet with one gallon of gelcoat if you produce a batch that is 20 to 25 milliliters in size and use it. Adding a catalyst to the gelcoat is essential, but it’s important to note that using too much can render the mixture overly runny.

Among your materials, gelcoat is available as a paste, liquid, or spray. Because the paste is used for repairs, you should always keep some on hand in case there is damage that cannot be immediately detected.

Your decision will determine whether you use a liquid or spray gelcoat for the painting process.

– If you use liquid gel coat, you need to buy a roller or brush hair to paint.

–  For spraying gelcoat, you need a special spray gun that is designed specifically for this purpose. You also need an air compressor with at least 10 gallons of reserve and an adjustable pressure control. The adjustable pressure control allows you to apply the gelcoat in different thicknesses and coats. It also depends on the specific needs of your project.

Step 9: Put on your first layer of gelcoat

Step 9: Put on your first layer of gelcoat

Step 9: Put on your first layer of gelcoat

After using wet sandpaper, the boat has to be allowed to thoroughly dry off. To get rid of any sand residue that might still be there, you can give the area one more application of acetone.

You are now able to begin painting the boat using the applicator that you selected.

+ If the spray bottle: Because this tool can become cloudy, a test spray is required to remove any fluid drips. When using a spray bottle, perform many tests to ensure that the paint comes out in an even layer.

+ If you use brush: When using a brush, you apply the paint in thick globs and then delicately sweep it on for an even application.

+ If using a roller: Before the paint has time to dry and form globs, ensure that it is evenly distributed. To make your work even neater, use a brush with thinner bristles. Remember that after approximately 15 minutes, the paint will harden and become more difficult to move around.

Step 10: Let the boat dry completely and sand the gelcoat

Once the gel coat has been applied, give it ample time to dry completely. Use a fan or other air flow to help speed up the drying process. To get the best results, you should apply at least two coats of gelcoat to your boat.
When the paint has had enough time to dry, give the layer of gelcoat a pass with your sander or a piece of fine sandpaper. The purpose when doing so is that it is sufficiently rough for the subsequent coat.

Step 11: Observe the gel coat

+ Case 1: Gel coating is worn and dull

With a special cleaning product, you can bring back the shine of your fiberglass and get rid of any dirt or debris. If more work is needed on the gel coat, begin by sanding down that area. Afterwards, make a combination of fiberglass filler and hardener to fill in any existing cracks until they are completely sealed. This mixture should bond effortlessly with the gel coat for an excellent finish.

+ Case 2: The previous gel coat is high oxidization

Using sand paper with a very fine grain, sand down the residual gel coat. Fill up the gaps and fissures. Acetone might also be used to remove the previous gel layer from the surface. When the hull has had time to cure, a new layer of gel coat may be applied using either a spray applicator or a brush. Put on as many coats of gelcoat as you feel are necessary.

Step 12: Polish up the boat’s gel coating

Polish up the boat's gel coating

Polish up the boat’s gel coating

After the gel coating is fully dried, you can polish it up with a buffer to give it a glossy finish. Be sure to use a low-speed buffer and only light pressure. Take your time and be careful not to burn or damage the gel coat. It may take several passes with different grades of polishing pads to get the desired look.

Step 13: Waxing the boat’s gel coating

Once the gel coating is polished up, wax it to give it a nice glossy look. Be sure to use a marine-grade wax designed for boats and apply it in thin layers. Allow each layer of wax to dry completely before applying the next coat. After the final coat has dried, buff off any excess wax with a soft cloth. A top layer of wax protects your boat against salt, minerals, water-borne pollutants, UV damage, etc.

Step 14: Final inspection of the boat’s gel coating and protecting it

Final inspection of the boat's gel coating and protecting it

Final inspection of the boat’s gel coating and protecting it

Once you’ve finished waxing the boat, it’s important to do a final inspection of the entire surface.

Apply a protective sealant to the boat’s gel coat to protect it from the elements and maintain its glossy finish. You should choose a sealant designed specifically for boats. Then you have to follow the manufacturer’s instructions for the best results. Once applied, your boat will be looking like new!

Note: If you don’t want to paint the whole boat but just want to edit a part of the boat’s gelcoat like the bottom of the boat, you can check out how to repair gelcoat on bottom of a boat here. In case you want to restore gelcoat, refer to this information through how to restore gelcoat on a boat post.

What to know about a gel coat

What to know about a gel coat

What to know about a gel coat

A gel coat is the outermost structural layer on a fiberglass hull. It is a thin, hard, and highly durable layer of epoxy or polyester resin-based material. This gives the hull a glossy finish and protects it from weathering elements.

After it has been given the opportunity to cure, gel coat binds with fiberglass, forming a lasting and glossy exterior. This action prevents or delays the destruction of the hull from water seepage and UV rays. The gel coat provides an additional layer of protection against any potential water damage or cracks in the boat.

Gel coat also strengthens the hull structure and provides additional protection against wear and tear.

Some top tips for gel-coating your boat

Some top tips for gel-coating your boat

Some top tips for gel-coating your boat

Choose and mix your paint correctly

It is essential to use the right type and ratio of resin and hardener when mixing your gelcoat. Read the product recommendations carefully and adhere to them.

When gel coating, use a lot of small containers

After the gelcoat is put on, it only takes ten to fifteen minutes for the painters to stick together. To get maximum efficiency with minimal waste, you should pour the paint into several little containers. Then you catalyze each one individually. This will make sure none of your gelcoat goes to waste!

Get rid of any extra hairs on the paintbrush or roller before use.

This will help to ensure that the paint goes on smoothly and evenly. Always check the label of the paint before you buy it and make sure it is suitable for the surface you are painting. Test a decent paintbrush to make sure it doesn’t leave bristles on the boat. Tape the roller head and pull it off. It will remove stray hairs.

Prepare some tools and fill them with thinner

Gel coats and applicators quickly dry out and clump. Therefore, keep the trough or beaker filled with the diluent. As soon as you finish painting, you can drop the roller into the solution before it hardens and becomes impossible to remove.

Allow sufficient time for the boat to dry

When the boat is done, let it rest and cure. Don’t rush to use it, as the paint coat needs time to fully dry and harden so that you can enjoy your boat without any worry of damage.

Make sure all the tools are properly cleaned

Before putting away your painting tools and supplies, wash them with warm, soapy water and let them dry properly. This will help prevent rusting, clumps, and other damage that can occur when tools are stored with paint residue in place. Keep your boat looking beautiful by taking the time to properly care for every part of it!

FAQs How to gel coat a boat?

Is gelcoat self-leveling?

GelCoat has a unique composition that makes it resistant to water and extremely long-lasting. Even when applied to vertical surfaces, GelCoat will harden and finish with a self-leveling appearance.

Can you gelcoat over gelcoat?

Yes, you can. But first, make certain that the surface is clean and clear of any dust or other particles. You wouldn’t paint new paint over existing paint without first preparing the surface.

Is it necessary to primer before applying gelcoat?

No, it is not necessary. Tuff Stuff marine epoxy primer protects exposed fiberglass from blisters and moisture. It also improves hull adhesion.

How much area may be coated with one gallon of gelcoat?

The amount of surface area that may be coated with gel coat is proportional to the thickness of the application. Generally, one gallon can cover between 35 and 75 square feet.


In short, how to gel coat a boat? Preparing and applying a gel coat to your boat is essential to maintaining its beauty, resilience, and longevity. Once you have worked through our 14 easy steps with care and attention, though, you will benefit from an improved aesthetic for your vessel. Investing in high-quality products will also be a huge help when it comes to producing a professional finish. So don’t put off learning how to do gel coat on a boat from!


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