1 | Prep Your Surface
If you apply your gel coat to a surface that isn’t properly prepared, you’re gonna have a bad time. Applying a gel coat to a painted surface is a no-go. If you are using your gel coat on a painted surface, you have to remove the paint first with a chemical paint remover (which we sell) or some elbow grease (which you should already have). If you are working on a surface that already has a gel coat or has a new fiberglass surface, begin by sanding it with 150 grit or lower sandpaper. Sanding the surface first will create a mechanical bond which will allow the gel coat to adhere better. Next, get out your Acetone and clean the surface to remove any dust or dirt.
2 | Get A Mil Gauge
You may be tempted to lay down a nice thick coat and call it a day. Don’t. For most applications, gel coats like to be applied in thin coats. If you apply too much gel coat, you can get sagging, drips, or uneven coverage; more importantly, you’re gonna waste gel coat. Using a Wet Film Mil Gauge will take a lot of the guesswork out of the job. We recommend 18 mils for most applications and never more than 24 mils. If you have any questions about what thickness is right for you, give us a call we will try to help.
3 | Gel Coat Catalyst
A gel coat without catalyst is just a waste; don’t be that guy. All gel coats need a catalyst to cure. Sherfab includes the catalyst when you purchase a gel coat free of charge. We’re cool like that. Before you start spraying, add the catalyst 2% by volume. See our chart for more details.
|GEL COAT VOL.||CATALYST (2%)|
|5cc 0.13oz.||20cc 067oz|
|128oz. (1gal.)||80cc 2.50oz.|
4 | Have a Plan
Once you have added the catalyst, you have about 15 minutes before the gel coat begins to get hard or, as we like to say, “gel.” That’s why it important to have everything prepared beforehand. Make sure your working area is free of obstacles and ready to go. Know where you want to start your spray and have your Wet Film Mil Gauge at hand to check for proper coverage.
BONUS PRO TIP. If you are moving a little slow, put your can in an ice bath and cool it down to around 60°F.
5 | Seal it with Wax
When applying the final coat, you will need to add wax, 1oz. of wax, to 32oz. of gel coat. The wax will seal the gel coat from oxygen and allow the gel coat to dry without becoming tacky.
6 | Buff it Out
If you are happy with your results, it’s time to really make your gel coat shine. Start with an 800 grit buffing compound using a buffer and work your way up to a 2000 grit buffing compound. We have a 4 step buffing kit to make your life easier.
Well, that’s it for today. There’s a ton more to know, but it’s a good start. We are just scratching the surface with these tips. If you have any questions about them or other projects, give us a call (909) 923-2200.