Matching gelcoat can be easy! Keeping this trick in mind. Place matching gelcoat in two categories, color value and shade value, blending the different pigments into your gelcoat to reach the same color as the boat. You want the gelcoat your mixing to become a little darker than the boat, this will give you a better visual on where you are with your color match. If the boat is more on the yellow side as your gelcoat looks more on the brown side then add a very small amount of yellow to bring closer to the boat color, once you obtain the colors to be some what in sync then use the shade value. Shade value is the color only lighter or darker, once you feel your color looks roughly close it’s time to make your gelcoat a couple of shades lighter by adding white gelcoat, a very small amount at a time until you obtain the correct shade value. You may use a very small amount of white pigment but using too much white pigment may give you a dingie transparent effect leaving you with a poor match.
Use small strings of tint using a toothpick to add to your gelcoat one string at a time checking color before adding more tint, most off whites start out by using dark yellow or yellow gold followed by dark brown and light brown at times, then add a touch of black for the rich oyster colors. When adding dark tints such as brown, green or black do not use strings of tint as they are too powerful, add eye droplet size or less is best when mixing a pint or 1/2 pint, keep tinted gelcoat in a cool place.
If tinting gelcoat avoid colors in tubes as this may only make you frustrated and could give you a very poor repair also leaving you with colored speckles in your finish. Color tubes have a short shelf life and are not the same pigment as professional tints, unless you just don’t care about the color.
When matching true colors, red, blue, black and so on use neutral gelcoat for base using clear gelcoat would be too transparent and should only be used for top coating. Clear gelcoat is most used with metal flake repairs.
If matching with white gelcoat you may want to bring a chip sample to your local fiberglass supplier before purchasing white gelcoat to see if the white gelcoat is darker than the chip sample, if so search for a brighter white. It is very important to start with a high quality bright white, many white gelcoat products appear to be bright white but may have a light grey or pink cast to them making it difficult or impossible to get a good match as many are intended for mold work or tooling.
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