resin Q's

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i have been making cardboard armor, and how does resin work? is it like paper mache or can you use it like a paint?

Polyester or 'Fiberglass' resin is a two part liquid plastic that is commonly sold for repair projects. A kit consists of a quantity of resin and a smaller quantity of catalyst or hardener. Adding the hardener to the resin in the manufacturers specified ratio (usually 1/10) will cause the liquid resin to cure to a very hard, yet brittle plastic. Using this resin in combination with fiberglass cloth yeilds a reinforced composite material that is strong, lightweight and rigid.

Poyester resin in it's uncured form is a hazardous material in it's liquid form as it gives off fumes that are harmful to the respiratory system and is a skin irritant. Adequate ventilation and the used of a vapor rated OSHA respirator are a MUST for workign with this material.

Essentially you're going to mix the resin with the hardener, then brush it over your form, lay down a layer of fiberglass cloth, then brush on another layer. Lather, rinse, repeat.

Polyester resin is very, thin and runny. By adding a thickeneing agent to it, like talc, or Polyfiber it becomes thicker and easier to brush on... more like a paste.

Links to poylester resin:

Links to Fiberglass cloth:

Links to Polyfiber:

EDIT: Links Fixed. :$ops:
and if you need to thin poly resin down abit add rubbing alcohol. Its also very good for cleaning it off your hands, but Id reccomend using some gloves while working with it.
Gloves and 'old clothes' are deffinately required. It's messy stuff, even when you are trying your best to be clean with it.

BTW Acetone is recommended for cleaning up resin, although it's not very good for you either. I wouldn't hold out for saving your brushes too much. Get the cheap ones so you don't feel so bad about messing them up. I just buy them by the case nowadays.
I know when working on my jango helmet, I mix up about 2 to 4 oz at a time. Any more than that and it all just runs off. LOL Dont be in a hurry! LOL
Yes youll want to apply about two or three heavy coats of just resin, then start applying inpregnated glass cloth on inside of that, say about 8 to 10 layers of glass. This should give you about a 3/16" thick outer shell, which is very strong and durable.
***Warning, stupid question about to follow****

So you do the hard resin on the outside, and use the fiberglass cloth on the inside?


how ever many layers you want.
The most efficient way to apply resin to glass cloth is whats called a pre-preg.

Pick up some mylar, or what we in the navy call peel ply (it doesnt stick to the resin). Lay sheet of peel ply down, then glass cloth, pour on your resin, lay the next sheet of peel ply down over that, and use a pencil, or tongue depressor to push the resin all over the glass cloth.

Then you peel away one layer of peel ply, and lay it where you want on your project. again using the tongue depressor (anything will work) and smooth it out, getting rid of the bubbles.

When its cured you simply peel away the peel ply layer left, and re use it.

If you can not get peel ply, then just make sure you use enough resin to fully saturate the cloth, it should appear bright white anywhere. And make sure you get rid of all bubbles. After its cure the bubbles become voids, that have to be filled in(just alot more work).

GL have fun

PM me if you need any other info, Id be glad to help.

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