fiberglass resto?

[Archangel]

Well, I just noticed that someone has hit the truck again, this time it was the driver side fender that got damaged - I got a nice hole in it, and a decent-size tear. The fenders are fiberglass, so I should be able to fill the damages and paint over, right? Any recommendations in the procedure?

Oh yeah, and I'm really starting to like the idea of installing a set of wheel-spikes like those on the trucks in the survivors' convoy in Resident Evil Extinction - you scrape me, you replace half your body panels :evil:

[CheeseSteakJim]

Could you post a good picture of the tear so I can see what it looks like?

First what you want to do is drill a 1/8" hole at the end of the tear to prevent spreading. Even if you repaired it by the book but didn't do that, eventually it will resurface and start to tear further.

[Archangel]

Jim, it ain't torn all the way through, besides the gash is fairly big, like the blunt front corner of a pickup truck hit it and scraped off the top layer of the fiberglass... I'll snap a pic of it tomorrow.

[P72Ford]

You'll need some fibreglass mat and resign, if material is missing. Grind some material off, and lay on the new resin soaked mat. Smooth it as much as possible. Finish it with filler (fibre reinforced if possible) and then putty.

If you can, grind/ sand off the surrounding paint so that the added mat only contacts the bare fibreglass. Thats how I've always done it, and thats how I see others do it. If there are small cracks or tears though, the hole drilling is required to prevent further propogation.

[CheeseSteakJim]

Grind all surrouding paint, or at least the clearcoat. General rule of bodywork: If it's shiny, nothing will stick to it.

You don't need any fiberglass mat if there's no hole or tear. If it's just a gash that didn't make it all the way through, just use fiberglass filler. You might even be able to get away with glazing putty if it's not very large. Fiberglass mat/cloth is only needed if there's a hole that will need support to really patch. If you just have a divot dug into the fiberglass you can just fill it and sand it level with a sanding block.

As with plastic filler (bondo), be careful with how much hardener you put into your fiberglass filler. Too much and it'll harden before you can use it. Too little and it won't ever completely harden, or may take days to do so. Ideally you want it to harden between 15 and 30 minutes after mixing, depending on how long your fix will take you to do.

[Archangel]

Okay, based on what you guys said, fiberglass filler it is - there are no through holes, just jagged surfaces with plenty of loose-end fibers. Sorry for the no pics thing, but my camera is dead and I can't find the damn battery charger nowhere!

[P72Ford]

No holes= fibreglass filler. But, I don't like to use fibre filled plastic as a topcoat. It generally makes it look pretty crappy; I would do a topcoat of putty to make it smooth.

[CheeseSteakJim]

Yeah.

Also, I might as well point out that fiberglass cloth and fiberglass mat are two different things. Fiberglass cloth is in a crosshatched pattern and is easier to work with. Fiberglass mat basically looks like a mess of fibers, and while it's weaker when it's dry, once resin is applied to it it's much stronger than cloth because there are no pre-defined lines at which is can split. When dealing with a split in a difficult area I like to do the first and second layer with cloth, then put on the mat.


Also, fibreglass anything is not produced or for sale anywhere in the United States, which is where this site is hosted, and where everyone in this thread is from, so don't listen to anything P72Ford says.


Just kidding. :p