how to apply gelcoat repair

1. Purchase a wax gelcoat repair kit that matches the color of the damaged spot. ...
2. Mix the new gelcoat according to the manufacturer’s instructions. Pour the amounts of each part recommended by the manufacturer into a plastic or paper disposable cup.
3. Press the gelcoat onto the damaged area with the mixing stick. Scoop enough of the putty out to overfill the damaged area by about 1⁄32 in (0.079 cm).
4. Let the gelcoat dry for at least 8 hours to cure. Leave the repaired area to dry overnight or for at least 8 hours.
5. Sand down the repaired area with 80-grit, 240-grit, and 400-grit sandpaper. Use a sanding block and sand in circular motions.
Buff the repaired area with an electric buffer and rubbing compound. Apply rubbing compound directly to the pad of an electric buffer and turn it on to low speed.
Apply a coat of wax to the buffed area to finish. ...

Full Answer

How do I restore the chalky gelcoat on my Boat?

• The best wax to use for restoring your gelcoat is marine wax. It's specifically designed for use on boats and it's waterproof. ...
• Use a cloth if you're applying the wax by hand.
• Use a foam pad if you're applying the wax with a buffer.

How to restore gelcoat on a boat?

Wax and seal the gel coat to preserve the sheen.

• Apply wax to the areas of the gel coat in a circular motion using a rotary buffer and a high-quality pad.
• Continue applying the solution without exposing it to direct sunlight until you’ve covered a significant portion of the boat.
• Make sure to rub away excess wax using a clean buffing pad.

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How to fix a screw hole in gelcoat?

How to Fix a Screw Hole in Gelcoat

1. Preparation. The first thing that you need to do is to prepare the hole which you need to fill. ...
2. Using the Repair Kit. Most stores will provide a little item known as a gelcoat repair kit. ...
3. Finishing the Project. Once you have filled the hole with paste, leave it for around a day, and then apply some sandpaper to the edge of the ...
4. Larger Repairs. ...

How thick can you apply gelcoat?

How thick can you apply gelcoat? Gelcoat can be applied in coats up to 24mils. For applications under the waterline a thickness of 20-24 mils aids in blister prevention and is better than thinner layers. Thicker layers are more prone to cracking under stress. Styrene vapors will inhibit and slow the cure of gelcoat.

What is the best way to apply gelcoat?

0:242:36Quicktips: How to brush apply gelcoat - YouTubeYouTubeStart of suggested clipEnd of suggested clipThe best method to apply gel coat by brush is to basically just load the brush. Each time you makeMoreThe best method to apply gel coat by brush is to basically just load the brush. Each time you make contact with the mold. You basically just spread it on just dot and a bit here and there.

What is the easiest way to repair gelcoat over fiberglass?

0:245:22How To Repair Boat Gelcoat [MATERIALS LIST ] | BoatUSYouTubeStart of suggested clipEnd of suggested clipSo to make a proper repair I've got to open up this little cracks of the gel coat the new gel coatMoreSo to make a proper repair I've got to open up this little cracks of the gel coat the new gel coat he's got something to buy into. So for that I'm going to use a dremel.

How do I repair gelcoat on my boat?

Wet-sand the cured gelcoat with 320-grit wet/dry paper on a soft sanding block. Confining work to the immediate repair area, continue wet-sanding with 600-grit paper until nearly even with surrounding gelcoat. Finish wet-sanding with 1,000-grit paper; then buff out with rubbing compound followed by a coat of wax.

Can you gelcoat over gelcoat?

Can You Spray Gelcoat Over Gelcoat? The short answer's yes. But first, make sure the surface is free from dirt and debris. Using the window frame analogy again, you wouldn't apply new paint over old paint without preparing the surface.

Can you apply gelcoat with a roller?

If you want to roll on a gelcoat, be sure to use a 1/8 “or 1⁄4” solvent-resistant nap. Be sure not to use foam rollers because they tend to leave the bubbles. If you brush on the gel coat, make sure to use a solvent resistant brush.

How do you prep fiberglass for gelcoat?

Before you gelcoat fiberglass, fill in any cracks or gouges with a polyester filler and then sand the damaged areas down with 80-grit sandpaper. Clean the fiberglass with soap and water and wipe it down with a rag soaked in acetone, and immediately removing it with a clean dry rag.

Can you apply gelcoat with a brush?

Applying Gelcoat by Brush or Roller – (Use a Brushable Gelcoat) When applying gelcoat by brush or roller, we recommend the Ultra Plus Brushable Gelcoat. (other Gelcoats are best applied by Spray) The Ultra Plus Brushable Gelcoat is designed for self-leveling and is a much easier application.

How do I get a smooth finish on gelcoat?

7:0710:46Making Boat GelCoat Look Good! - YouTubeYouTubeStart of suggested clipEnd of suggested clipIt's best to use a large trowel on the big spots. And we'll use a smaller knife on the smaller spotsMoreIt's best to use a large trowel on the big spots. And we'll use a smaller knife on the smaller spots. The same thing goes for the inside of the transom. We want to continue filling in the spots.

How do you blend gel coats?

1:3920:51Ashland | Gelcoat Repair Video/Training - YouTubeYouTubeStart of suggested clipEnd of suggested clipMake sure the gel coat has been properly agitated. Agitation is key to maintaining the correct cureMoreMake sure the gel coat has been properly agitated. Agitation is key to maintaining the correct cure in color of the gel coat patch mix the gel coat for 10 to 15 minutes prior to pulling the sample.

Should I use gelcoat with or without wax?

The first coat of gelcoat does not need the wax since you will apply a second coat. When mixing gelcoat for the second coat, though, don't forget to add in the wax additive. All Gelcoats from the Bottom Paint Store comes with the MEKP catalyst and wax additive sanding aid, but additional amounts can be purchased.

How thick can gelcoat be applied?

20-25 milsSpraying gel coat is recommended for more accurate and consistent coverage. Apply gel coat in 4-5 layers at approximately 5 mils each, allowing 15-20 minutes between layers for a total thickness of 20-25 mils. Use #122-A Gel Coat Thickness to ensure proper thickness is achieved.

How long does gel coat take to cure?

Most re-sprayed gel coat will cure in 2-4 hours, although overnight cures are ideal. Begin wet sanding with the finest grit that will remove orange peel in the re-sprayed area. This will avoid unnecessary sanding scratches. Usually 320 or 400 grit wet paper is sufficient for the initial sanding.

Can you gelcoat over fiberglass?

First thing you want to do is look at the surface you want to apply gelcoat to. If the surface is already covered with gelcoat, or if the surface is a fiberglass, or polyester resin, then applying gelcoat will be a snap. If the surface is paint, then the paint would have to be removed before applying the gelcoat.

How do you fix peeling gel coat?

1:413:12How to repair Gelcoat Part 1 - YouTubeYouTubeStart of suggested clipEnd of suggested clipThey would need to be widened. So that the new gel coat has good surface area for bonding as you canMoreThey would need to be widened. So that the new gel coat has good surface area for bonding as you can see in this animation gel coat cannot penetrate very small cracks. The solution is to widen them.

Should I use gelcoat with or without wax?

The first coat of gelcoat does not need the wax since you will apply a second coat. When mixing gelcoat for the second coat, though, don't forget to add in the wax additive. All Gelcoats from the Bottom Paint Store comes with the MEKP catalyst and wax additive sanding aid, but additional amounts can be purchased.

How do you fix deep scratches in gelcoat?

As long as the gelcoat around the deep scratch is in good condition, you will be able to use gelcoat putty , requires mixing MEKP catalyst-once mixed properly it can be worked with a putty knife for filling, or you can make one using gelcoat and an aerosil filler/thickener.

How long does it take to repair gelcoat?

Use a small wood or plastic putty knife to spread the gelcoat smoothly over the gelcoat repair. You should have about 10 to 15 minutes of working time after adding the catalyst before it starts to harden and is no longer fluid. Fill the repair slightly higher than the surrounding surface to allow for sanding.

Can you repair a fiberglass boat?

You can successfully complete basic fiberglass boat repair by following these steps.

Can you gelcoat a boat?

For these, call in a pro. Also, deep gouges may need structural fiberglass work or filler before you repair the gelcoat. On horizontal surfaces, liquid gelcoat works, but for vertical surfaces, a paste is easier to apply. The first step is identifying the finish on your boat.

Do you need to fill gouges with epoxy?

You'll need to fill deep gouges with resin and filler before applying finish. Epoxy resin and fillers adhere better than polyester products but cost more and require several extra steps prior to applying the finish color of either gelcoat or boat paint. If you choose paint, topside alkyd enamels, polyurethanes and others are available from Interlux and Pettit.

How long does it take to apply gelcoat?

Be sure to have a plan of attack for applying your gelcoat. Once you mix it, you have about 15 minutes to apply the gelcoat before it starts to get hard or “gel.”. The actual working time depends on your amount of catalyst and how hot your working conditions are.

How thick should gelcoat be?

Gelcoat needs to be applied relatively thin. We recommend 18 mils thick, to properly cure. 18 mils is approximately the thickness of a matchbook cover. If you aren’t sure how thick, pick up a mil gauge. It’s a quick, easy way to see the thickness of your gelcoat.

What is the second coat of catalyst?

Your second coat will consist of the same amount of Catalyst, but if you are doing one more coat, your next coat will include Sanding Aid, or ‘wax.’ You will mix in 1 oz per quart to the gelcoat, which will seal the surface from oxygen, causing the gelcoat to dry tack-free. If you roll or brush your seconding coating, be sure to go the opposite direction from the previous coat, allowing a uniform coating.

How much methyl ethyl peroxide is needed for gelcoat?

Gelcoat requires Methyl Ethyl Ketone Peroxide or MEK-P to activate the hardening process. The amount is very small. We recommend 1-1/4% to 1-1/2% by volume, which means 13-15cc’s per quart.

What nap to use for gelcoat?

If you decide to roll on the gelcoat, be sure to use a solvent-resistant 1/8” or ¼” nap. Be sure not to use foam rollers, as they tend to leave bubbles. If you brush it on, be sure to use a solvent resistant brush. Your first coat will simply consist of the gelcoat and the MEK-P catalyst.

How many grits to use for gelcoat?

At this point, you can use an 800 grit compound to compound the gelcoat. You want to use a buffer that turns at 1600-3000 RPM’s. The car polishers will not work, as they spin too slowly, so you want to check the spin speed. It’s best to do a 4’ by 4’ area and go from there. Every 10’ or so, you will want to clean your pad with a spur or with some air to ensure pieces don’t scratch your surface.

Can you apply gelcoat before painting?

If the surface is already covered with gelcoat, or if the surface is a fiberglass, or polyester resin, then applying gelcoat will be a snap. If the surface is paint, then the paint would have to be removed before applying the gelcoat. So, you’ve decided the surface is gelcoat, so it’s time to begin. You want to sand the surface to create ...

How to apply gelcoat to fiberglass?

To apply the gelcoat with a brush, dip the brush in the gelcoat so there’s a liberal amount of gelcoat on it. Brush the gelcoat onto the fiberglass using short vertical strokes. Avoid spreading the gelcoat too thin or you’ll get stroke marks. You want there to be a thick, even layer of gelcoat on the fiberglass.

How to protect gelcoat from fading?

Apply a wax over the gelcoat to protect it. Wax will also make the gelcoat shinier and more reflective. Use a wax designed specifically for gelcoat or fiberglass. Use a cloth to apply enough wax to the fiberglass that there's a thin, visible layer over the entire surface. When the wax dries, buff it off with another cloth.

How to remove wax from fiberglass?

Wipe the fiberglass down with acetone to remove grease and wax. This step is especially important if you’re gel-coating old fiberglass that already has a coating on it. Removing any grease or wax on the fiberglass will help the gelcoat adhere better to the material’s surface. Once you’ve gone over the whole surface with a rag soaked in acetone, and immediately removing it while still wet with a second dry rag.

What is gelcoat used for?

Gelcoat is a liquid that hardens to form a thick layer that's used to protect fiberglass and give it a shiny, smooth finish. Applying gelcoat to fiberglass is simple if you have the right tools and take care to mix your gelcoat properly. Steps.

How to use a gelcoat sprayer?

To use a gelcoat spray gun, fill the plastic container on the gun with your gelcoat. Then, attach the cord on the gun to an air supply source, like an air compressor. Hold the spray gun about 1 foot (0.30 m) away from the fiberglass and spray the gelcoat onto it in short, even strokes.

How to clean fiberglass before gelcoat?

Clean the fiberglass surface with ajax or comet and water. It’s important that the fiberglass is clean before you gelcoat over it. If there’s any dirt or dust on the fiberglass, it will get trapped under the gelcoat. Go over the fiberglass with a soapy rag and then wipe it down with a clean rag to remove any leftover suds.

What is polyester filler?

Polyester filler is made of the same material as polyester resin (AKA fiberglass resin). It will bond and be of similar hardness.

What Is Gelcoat?

Gelcoat is an epoxy or polyester resin-based thermoset polymer that is usually applied to the boat exterior during the fiberglass molding process to give a smooth, shiny appearance.

How to remove PVA from a drywall wall?

Finish with a light sanding using 1,000-grit paper and buff the area with rubbing compound. Buffing gelcoat must be done delicately so as not to create heat that can stain the surface. Finally, apply a coat of wax-based gel coat polish .

How to restore gelcoat on boat?

If your gelcoat has oxidized, giving it a dull, chalky appearance, you can simply use a gelcoat oxidation remover to sand and polish the surface to a low sheen without the need for full repairs.

How much does it cost to repair gelcoat on a boat?

For large surface repairs, it is recommended that you take your boat to a professional, which can cost between $70 and $110 per hour .

What is Durabak overcoat?

Durabak is a more heavy-duty and flexible alternative to gel coat that won’t crack or peel over time or get scratched from impact.

How to clean Durabak paint?

Before applying Durabak, you need to clean the entire boat surface with a mild household dish detergent. Once dry, roughen the surface with 40-grit sandpaper and wipe clean with Solvide or xylene solvents. Tape off any areas that you do not want to paint with Durabak.

How to repair a gouge in a car?

For deeper gouge and scratch repair, you need to use a power drill with a conical grinding bit to create a V-shaped notch to improve the bonding surface. Use 80-grit sandpaper to remove loose chips and create a shallow bevel. Clean up the entire area with acetone.

How to apply gelcoat?

If it’s a spray applicator you need to fill the container, attach the hose to an air compressor and apply the Gelcoat with short strokes. When applying the short strokes gradually move outward from the repair area. Leave at least 20 minutes in between applications for the Gelcoat to flash off. You might need to reapply the Gelcoat more than 5 times to achieve a great result.

How to protect gelcoat from splatter?

Use Tape On The Area. Use paint tape around the damaged area to make sure you protect the surrounding surface and mark the area you are going to work on. Use the tape on any other sensitive surface to make sure it is fully protected by splatter from the Gelcoat.

How to buff PVA?

Afterward, get 600 grit sandpaper and keep on wet sanding till it’s flush with the area around it. Next, use 1000 grit paper and add a rubbing compound to the area to buff it.

How long does it take for gelcoat to flash off?

Leave at least 20 minutes in between applications for the Gelcoat to flash off. You might need to reapply the Gelcoat more than 5 times to achieve a great result. If you are using a foam brush or a roller to apply the Gel coat you will need to do it in short vertical strokes to get the best result.

What to use to fix a deep scratch on a boat?

Use The Filler. If you are fixing a deep scratch on your boat you will need to apply resin and a filler. The filler can be polyester-based or epoxy-based. The epoxy-based filler is better and lasts longer but it is a bit more expensive.

What is gelcoat on a boat?

What Is Gelcoat? Gelcoat is a polyester resin polymer that is used on a boat’s exterior which gives a smooth and shiny look to the fiberglass . The Gel coat also protects the fiberglass boats from water damage and UV damage. Although Gelcoat is very durable, it can deteriorate as time goes by.

Why does gelcoat crack?

Gelcoat can also lose its integrity and durability on speed boats that go really fast, which causes the applied Gelcoat to crack. The Gelcoat can also get damaged by the elements and environment but the biggest threat to it is an impact by some underwater hazard like reefs or rocks.