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Old 02-12-2013, 03:54 PM
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Originally Posted by NEW INTERIORS View Post
One has wax and one doesn't... That is the only difference between the two... One doesn't stick more then the other... I only use the one that doesn't have the wax....

There is two types of resin..epoxy and polyester..

Vinylester resin, Formaldehyde Resin ETC cant forget those! There is also a different coating on the glass fiber for the different types of resin your using so the resin can bond to the glass or other fibers!

No difference in the non waxing and waxing resins, There's a big difference LOL, Or there would only be one formula! Like the cheep general purpose economy resin cut rate shops use! And if your doing overhead or vertical work your large areas of woven cloth or mat would fall or slide off!

Laminating resin dries tacky! You don't sand laminating resin, Its tacky to hold your next layer in place and to aid adhesion when applying more layers and helps the Finnish coat adhere to it and the product or repair dries hard and can be sanded or prepped or jell coated!

A lot of custom parts are built using epoxy resin. The issue is efficiency and cost. Epoxy, though a superior technology, costs 2 to 3 times as much as polyester resin and it must be washed between layers,polyester laminating resin needs no prep between layers! Both Epo. and Poly. resins can be used to mold fiberglass, but polyester is more controllable by the amount of catalyst added so production time is reduced- get the finished part out of the mold and get another one started. Epoxy resin is used to make the molds that polyester resin fiberglass parts are made in though!

Epoxy molded fiberglass must also have a surface finish applied! So Polyester resins are used for this! First gel coat the mold and then the laminated layers added and out pops a shiny new part.

249 polyester resin, it drys clear as water, other polyester resins have a blue or green tint

vinyl ester resin is stronger/tougher but is not as clear so not used much with color tinting or carbon fiber.

epoxy resin is the strongest and bonds better with automotive plastics. When using it with carbon fiber it must be U.V. protected in sunlight with a good non yellowing clear. Epoxy is no good for any kind of heat and it will become rubbery at a low temp. It does resist spider cracks but isn't as flexible as polyester resin.

I can apply heat to a Corvette top, rear, front fender corner and apply pressure to get it back in position apply cold and it will stay there! you cant do that with epoxy resin parts!

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