One of the most distinctive features of a vintage buggy is that it uses fiberglass body, which is as strong as steel but with low density and good heat-insulating property. Then how to make a good fiberglass product?
It consists of 11 procedures, mold cleaning, mold release agent applying, resin coating, glass fabric cutting, gum mixing, pasting, room temperature curing, demold, edge banding, curing, painting.
1. Mold cleaning. Cleaning up the mold. Wipe up the mold with soft gauze. No remaining impurities on the surface.
2. Mold release agent applying. Apply the mold release agent on the mold evenly and ensure there is no omission
3. Gel coat resin coating. Intensively mix the gel coat resin ingredients, especially when there are fillers and pigments. Spots or strips may occur on the product’s surface if under-mixing, which will affect the appearance. Control precisely the thickness of the gel coat. Apply gel coat with a brush. Wait until the gel coat solidifies. Touch it with fingers, feeling slightly sticky but does not stain the fingers. Then start layer pasting.
4. Glass fabric cutting. Pre-calculate how many fabric layers are needed according to the product’s dimension and thickness. The glass fabric should be bigger than the mold.
5. Gum mixing. Choose suitable type and proportion of curing agent and accelerant according to gel time and environment. Add a little mill base if making colored product.
6. Pasting. Firstly brush evenly a thick layer of resin on the gel coat. Secondly paste the first layer of glass frosted reinforced material. It’s better to use surfacing mat or glass cloth with thickness of 0.16mm. Then tighten with a brush, which makes the resin percolate the glass fabric. Don’t apply resin on it until the glass fabric is totally percolated. Paste the following resin and glass fabric in the same way until it reaches required thickness. Make sure glass fabric totally percolated for every pasting. Every glass fabric should be free of air bubbles and attach closely on the mold. After multiple trails, it is suggested to use one layer of chopped strand mat after one layer of surfacing mat, and then paste glass cloth until reaching the needed thickness. In this way, it avoids the fiber cloth line to appear on the gel coat, which insures surface quality of the product.
7. Room temperature curing. Leave the product on the mold for more than 24 hours to complete curing.
8. Demold. Release the product from the mold, starting from the edge. Blow compressed air between the product and mold. Deburr along the cutting line and remedy defects: use sweep-saw or angle grinder along the edge of the product and remedy the defects.
9. Edge banding. Glass fabric is non water-proof. The fabric on the cutting face is exposed. Once this part is soaking, it may cause the product layered, which affect the product’s quality. This problem can be solved by edge banding—brush evenly on the cutting face a thin layer of resin which is mixed with curing agent and accelerant.
10. Curing. Leave the product after demolding for more than one week to ensure the product totally curing
11. Painting. Clean up the mold release agent from the product. Paint it with low temperature lacquer.