It is over 25 years ago since I used fiber glass. At that time there were two forms easily available, woven fabric and what is called random mat. Both fabric and mat come in various weights. My understanding is that the random mat is more pliable and stronger, it consists of glass fibers which randomly run in all direction. As a result you can pull and drag it to some extent in various directions and it will conform to different shapes where as the fabric, like a canvas tent or even something like a table cloth needs a lot more cutting and folding to make corners for example or it bunches or wrinkles over curves. You can blend the random mat over darts you might cut to accommodate a curve and blend patches over and make the seam essentially disappear but if you lay a strip of the fabric over a seam you can't easily hide the extra thickness.
the Polyester resin varies in quality, the better stuff is clear. The catalyst I used to buy comes in a plastic bottle with a small nipple, the idea being that you count the drops you add to a given quantity of resin. It takes a certain amount of temperature for the stuff to cure what ever the amount of catalyst but a little more in cooler weather can persuade it to set up. Too much and ht it gets pretty hot, apparently it can even catch fire. You can add die to the resin to colour it, the advantage being that the colour ends up through the finished product. Random mat glass is easier to work the texture out of. The woven fabric tends to bleed the screen like texture through more layers of resin. In manufacture they do it a little differently. Usually they use a gun and fiber glass rope. The rope is chopped mechanically into short lengths of fiber which is mixed with a spray stream of resin and hardener and sprayed into molds. The mold is carefully prepared as a negative mold and carefully waxed so it can be more easily removed from the resin when it sets up. They start with a thin jell coat which produces that finish then layers of the glass and resin are built up on the inside including any metal or wooden reinforcement. I mostly built up layers of resin with those disposable paint rollers. Clean-up is a bitch! Best to just throw away applicators in my experience. Solvents like acetone or ethyl acetate can clean it up if it hasn't cured but not easily. don't let your hair get into it, you have to cut the hair off. It is sticky like sticky! I never did produce truly fine jell like finishes, never used molds but I suppose with enough fine sanding and tin finish coats one can get a glassy finish, certainly they do it with car filler. Hope this is helpful. If I was Han Solo I'd probably pet my wookie ----- Original Message ----- From: Jerry Richer To: [email protected] Sent: Saturday, January 16, 2010 7:01 AM Subject: [BlindHandyMan] Anyone ever used Carbon Fiber or Fiber Glass? I'm considering using Carbon Fiber to make some model boats and airplanes. I've been advised to experiment with Fiber Glass first because the techniques are similar but Carbon Fiber is considerably more expensive than Fiber Glass. Have you had luck working with either. Jerry [Non-text portions of this message have been removed]
