Hand lay-up FRP – the use of chopped strand mat

The process of hand lay-up for FRP
The surface condition of the hand lay-up FRP products。
In order to improve the value of the product, ensure the inner FRP doesn’t corrosion and prolong the product life. We usually make the article surface into a layer with pigmente paste(paste) and high level of resin. It can be just resin, and also be enhanced by surface mat. This layer is called gel coat layer (also referred to as surface layer or decorative layer).
When use chopped strand mat as reinforce materials, preferably using different specifications dipping roller operation, because impregnation roller to exclude air bubbles within the resin are particularly effective. If without such tools, we have to dipping with a brush, we should choose a good method to brush resin. Otherwise the fiber will be messed up and displacement. And resulting in uneven distribution and varying thickness. The chopped strand mat reinforce material shopped inside the deep corners. If we just use brush or roller dipping, it will difficult to close of bonding. So we should press smooth by hand.
When pasted, we use a roll coater glue coated on the mold surface and then manually spread the cut pieces of chopped strand mat on the surface of the mold and smooth, then glue the rubber roller, rolling back and forth, the resin glue immersion into the mat, then extrusion all glue from the mat with plastic foam roller and air bubble, then pasted the second layer.
If you encounter at the corners, you can manually torn the mat by hand, facilitate coated overlap, between the two mat pieces about 50mm. Many products can also be used in ply ways alternating chopped strand mat and glass cloth, Such as Japan company fish boat is a paste made of alternating method, it reported a good performance of the products made by the method.