Fiberglassing 101

[Da67goatman]

Does any one know of a good "fiberglassing for idiots" tutorial video or book?  I need to do a small bit of repair work on one of my cargo door trims where the corner has worn away.  Thanks guys and gals.

[1980c10]

for something like that you could just wing it, read the directions is all. I only tried fiberglass a couple of times on cracked fiberglass hoods etc- but nothing to it.

[Lt.Del]

Sand down the paint to bare metal (err, fiberglass).  Cut the fabric ahead of time to size...oversize just a little. After adding the hardener, work fast and wear latex gloves.  Dip the fabric in the gel and, working fast, smooth it out over the patch area, trying not to get wrinkles in it (or you'll have to sand that out later).  The threads seem to want to pull loose around the edges, but that is expected.

You may have to apply 2 or 3 layers, depending on your goals. Then sand, prime, sand, prime, sand, etc..Primer lets you see the low and high spots for more sanding or more buildup.

[1980c10]

Sand down the paint to bare metal (err, fiberglass).  Cut the fabric ahead of time to size...oversize just a little. After adding the hardener, work fast and wear latex gloves.  Dip the fabric in the gel and, working fast, smooth it out over the patch area, trying not to get wrinkles in it (or you'll have to sand that out later).  The threads seem to want to pull loose around the edges, but that is expected.

You may have to apply 2 or 3 layers, depending on your goals. Then sand, prime, sand, prime, sand, etc..Primer lets you see the low and high spots for more sanding or more buildup.

right on, the steps are simple, it is the technique that counts to save time and that comes with practice.

[Da67goatman]

How do I get it to keep its shape?  I am fixing the top corner of a cargo door trim piece.

[Lt.Del]

it's hard to picture what you're fixing without a, well, a picture.  But, when you place the fiberglass down it will stay in the shape you apply it due to the gel mixture and hardener---in fact, once you put it in place, it is hard to move it around if not impossible....make sure it goes in the correct location and position as you apply it, because you won't be able to move it without really messing things up.  

http://www.youtube.com/watch?v=r8cPiOC3tp4

[Da67goatman]

In that case here's a picture.

[Lt.Del]

that shouldn't be a problem.  I'd put about two layers of fiberglass on the INSIDE of the trip to build a base.  Then perhaps one layer afterwards on the front side.  You'll have to sand the front side a bit after she dries, but that shouldn't be a problem.  The fabric will still in place on the inside if you overlap about an inch in each direction.

[Da67goatman]

Ok, thanks guys, been a big help.

[Blazin]

You need to grind away any lose strands and crappy glass. Then grind away from the repair area and bevel it out as you got until your flush with the existing glass. I use glass mat rather than cloth, sometimes I will use a combonation.Your first pieces want to be the correct size for the missing portion, not bigger. Then the next pieces need to be a little bigger, then bigger, and bigger. That way you are building up the thickness you want. As for making it to shape use masking tape to make a form, then do as SgtDel said and build it back from the inside. Once that is dry You can lightly grind the outside, and layer some on there. Don't apply any to unground areas as you need that mechanical bond. The glass makes the strength not the resin, the less resin you use the better. You only need just enough to wet the glass all the way through. Use a brush to apply a thin coat to you tape mold, then press the glass into that resin with the tip of the bristles, if its dry a little more on top of the glass until its wet through. Use the ends of the bristles to dab to repair. It will make the resin foamy a little. Brush off the excess you get from this process. Then add you next layers.