Fiberglass fix-it help

Trying to strengthen the fender-to-body section on my ECJ5 fiberglass fenders. I've never dealt w/ fiberglass repair before, so I need advice.

Bought a small boxed fiberglass repair kit from NAPA. It contains "resin", "hardener", "fiberglass mat or cloth", mixing tray w/ stirrer & spreader. Granted, I've never seen these thingys before. Problem is, the directions speak of using "release paper" and there is no such thing included. Am I supposed to know what the heck that is/does? :?

Look at the pic below. I just want to strenghten the ends where it's cracked/weak. Can't I just mix the resin & hardener & glob it in the corners ala JB weld??

 

I've done a moderate amount of fiberglass fab and repair. My guess of the "release paper" would be something like waxed paper that wouldn't allow the mixture to stick to an area you don't want stuck. Don't think that you need it in this situation. Normally a mold release agent similar to car wax is applied to a mold so that the mold can be used more than once.
The mat or cloth that's in the kit gives the resin/hardener mixture "body" and strenthens the piece, kinda like rebar in concrete. Try to use at least a little of the cloth or mat in the area you're going to repair, otherwise the repair will be weak and you'll probably be doing it over again . Several layers of cloth or mat saturated with resin/hardener is best. Also, be sure to scuff-up the area you're repairing with some course sandpaper so the resin/hardener will have something to adhere to. If you haven't done so already, get a quart of acetone to clean up any tools, spills or anything else that you don't want stuck - the stuff can be messy - like a clear roofing tar. Wear latex gloves - unless you want to strengthen your fingernails. R)
One last thing - pay close attention to the resin/hardener ratio - too little hardener will cause the mixture to take a loooong time to set up. Other than that - no problem. Good luck!

 

I help. I do AB for my job and I work w/ fiberglass all the time. The old resin and cloth works Ok, but there are newer, stronger methods. I don't know if you have an auto body supply store near you, but if you do I'll tell you of some products that can help. 3M makes an SMC/ fiberglass repair adhesive that comes in 2 part dispenser tubes, they call it "Automix" Or Lords(brand)- "Fusor" or Norton( Brand name ?). It is a 2 part chemical reaction which is a glue. You use this with matting or cloth. Cloth may be easier for you to use starting out, this is because it can be dificult to get the adhesive to penetrate all of the matting because it is thicker than the cloth.
What you do is grind the paint and gel coat back 2-3 inches from the crack/ hole. Then take a die grinder or piece of sandpaper etc and make a "V" (cross section) out of every crack you can find. Search carefully to get every crack otherwise they may exp/contract later and re-crack your paint. Blow off the area and apply your adhesive and matting. I like to put a layer of adhesive on all the bare areas, then coat a piece of matting and place over the area. I like to grind it (after hardened) just lower than the surr. area and fill the low spot with "tiger hair" or long stand fiberglass filler (its real strong). Level, smooth and put a little filler over. Primer, sand and paint

Sounds like a piece of cake right!
Josh