Polyester Resin is commonly used in industry for Fiberglassing (fibreglassing) applications due to its ease of use and low cost of manufacturing. Polyester Resin is mixed with MEKP catalyst in a ratio of 1% catalyst to resin for it to cure. Polyester resins can be purchased as general purpose resin commonly known as orthophthalic resin and high strength isophthalic resin.

Polyester Resin can be used to saturate fiberglass cloths, like chopped strand mat, e-glass, s-glass and roving to reinforce natural and synthetic surfaces for water proofing and durability. Other structural additives like glass bubbles, cabosil, industrial talc and chopped fibers can be added to a poyester to make a putty or paste which can be used to laminate materials, body fill surfaces, fill cracks and strengthen hard to reach areas. 

 This technique is used in the manufacturing of hot tubs, showers, tubs, holiday trailers, campers, RV's, boats, canoes, kayaks, automotive and trucking industries. Polyester resin is compatible with most other adhesives, but it is recommended to use the same resin system through out a project, where incompatibility of adhesive and bond strength will not be a factor in the final result.

This resin system has a very fast curing time, generally 90 minutes at 1% catalyst and 21 degrees Celsius, so complex lamination and large surface areas must be accomplished in multiple batches of resin. Specific tools like aluminum ribbed rollers, spreading tools and chip brushes are also able to be used to speed up the saturation process. 

Polyester resin is not a UV stable resin system, and therefore is often coated with gel coat or specific paints depending on the industry standard, wear and tare and water resistance required. Tooling Gel Coat can be used for making low production run polyester molds since the tooling gel coat is a hard smooth surface. Tooling gel coat is waxed and polished and can be used as a mold surface.