The idea of using it is not applicable for the selection of gel coat curing agents. Relatively inexpensive resin curing agents often have more troubles when used in gel coats, such as pinholes, bubbles, or insufficient strength, as well as additional losses caused by a series of repair measures.

Due to the lack of glass fiber reinforcement in the gel coat and its extremely thin thickness, the activity of the curing agent becomes very important in selecting the gel coat curing system. Methyl ethyl ketone peroxide (MEKP) with low reaction activity and low levels of hydrogen peroxide, water, salt, and ethylene glycol is often recommended for most gel coat curing.

The typical dosage of gel coat curing agent is 1.5-2% (relative to the weight of the gel coat). The decomposition of free hydrogen peroxide will form very fine oxygen bubbles, thereby increasing the possibility of pinholes appearing on the surface of composite materials. These pinholes are often observed when using low-end MEKP curing agents. The amount of bubbles caused by hydrogen peroxide will not behave the same in different gel coats.

Water, additional air caused by the viscosity and thixotropy of the gel coat, and inappropriate methods for making the gel coat can also lead to the formation of pinholes. Excessive water and polar solvents such as ethylene glycol in the curing agent can cause bubbles on the surface of the product. The high ethylene glycol content or excessive water in the low-end curing agent can also cause an increase in the thixotropy of the gel coat, making it thicker and more viscous, locking in more air, and making it more difficult to operate.

Therefore, the use of low water content and non polar solvents as gel coat curing agents is very important for gel coat curing. For example, V388 is positioned for resin curing, although it can also cure gel coats, the final product effect is significantly different from using M50 gel coat curing agent.

Choosing the correct gel coating curing agent is the first step in achieving a perfect spray effect on the actual gel coating. If you make a mistake at the beginning, you will be very passive and may end up paying a higher price.