Widening fiberglass fenders

[34Vette]

Anybody have any advice on working with fiberglass? My steel 34 chev has f/g fenders and running boards that need to be widened about 1 1/2" to 2" to clear the tires due to the vette suspension. I know that 2" wider rear f/g fenders are available but since I have all the pieces I will try to work with them. My plan is to split them on the high point of the curve which is basically flat. I'll need to grind and prepare both cut edges and build up fill the space with cloth and resin. I'm planning on making a jig to hold parts in alignment on the finished side so I have some work room on the inside of the pieces. Will I need to add some steel strips across the cut for reinforcment or will the cloth and resin be adequate? Of course the original steel fender braces will be widened and reinforced.

[Scotty]

It sounds like you are going about it correctly. Steel reinforcement is not necessary, the fiberglass will provide its own strength. Due to the different expansion & contraction rates of fiberglass & steel, the joint could show up at certain temperatures. Make sure that the edges are beveled well. I would use fiberglass cloth for the first layer or two of the joint & then bring it up to level with fiberglass mat. On the underside after the joint is level, I would put a layer or two of cloth extending well past the joint area to tie into the original fender.

Scott

[johnny37]

Maybe think about widening the running boards too to keep the lines consistent so that no one really notices the widening. They'll just think it all looks way cool.

[34Vette]

Thanks for response guys. Scotty, sounds like you have had a kick at the can before with f/g. Should I try to put a cloth layer on the finish side of the fender also or just try to add a thin layer of resin as required to match contours. It will probably become very elementary when I get heavy into it but a little heads up on what I may encounter sure would help.

Yes my plan is to widen the boards also. I'm just hoping that the thing doesn't get to looking tooooo wide. I'm using the vett wheels and the tires are about 11" wide. My brother said it looks like a steam roller from the front end now. I'm putting bumpers front and back which kind of hides the tire width a bit so it should be acceptable.

[Scotty]

When I worked in bodyshops I always got stuck with the fibreglass work because the dust didn't bother me(itching) as much as the other guys.:rolleyes: Cover all exposed skin, wear gloves, eye protection, and respiratory protection to minimize discomfort and protect your health.

The cloth does give more strength due to the weave tying the fibers together. However, if you use it for the final layer and then grind or sand down into the fibers, you are compromising the strength of the cloth and losing the benefit you were trying for. I find the mat is easier to use to get your final contours and it makes no difference how much you sand or grind it.

You're right, its pretty straightforward once you start playing with it. Here are some general instructions for those who may not know.

Cut your material to size. Mix hardener into an amount of resin you can use in a timely fashion. Use a disposable container such as a paper cup, or clean tin can. Place the mat or cloth on a clean piece of cardboard and apply resin, (I use a paint brush) flip over the material and apply more resin, brush resin on the panel where the material will be applied, then pick up the material and apply it to your repair area. Make sure the cloth or mat is completely saturated and work out all air bubbles. When done applying, clean the brush with thinner and you should be able to reuse it several times, or buy many cheap ones and throw them out. Wear disposable surgical gloves for easy clean up. Pretend your Ed Roth and have fun.:D