I saved the biggest crack in the Viper's hood for last. This crack goes all the way across the hood from the scoop to the headlight. The lower corner was cracked off too.
Like everything else, this giant crack was never repaired right. Even though the crack was actually fixed with fiberglass, all the damage wasn't removed. There is still a lot of delamination along the edges of the crack.
The surprises never end when redoing someone else's work, you never know what you're going to find. In this case, a lag bolt, just chillin' between the top and bottom layers of fiberglass. No reason for it to be there, it wasn't holding anything. This is about as far down as I ground the fiberglass too. While it's still mostly solid, it's paper thin and is only there to provide enough backing to keep the new fiberglass from sagging.
While I'm thinking about it, I'm not sure if I ever explained why I'm using fiberglass mat instead of woven cloth. Thickness for thickness, woven cloth is stronger than mat but it's harder to work with. It doesn't go around corners as well as mat does. Being easier to work with isn't the primary reason through, the real reason is shrinkage. Fiberglass and bondo shrink a tiny bit for awhile after they set up. If you don't properly cure, then post cure your work it will shrink more. Even if you do it right, fiberglass and bondo will still shrink a tiny bit over time as the remaining VOCs slowly evaporate out. This is the biggest reason why I wanted to get the fiberglass and major bodywork work done last fall, and wait to paint it next summer with many hot days in the sun in between, to give the bodywork time to shrink before final sanding, priming, and painting. If/when the bodywork does shrink, the weave of the fiberglass may become visible. Our eyes and brains are GREAT at picking out patterns. If you use woven cloth, your eye will be drawn to the obviously square weave pattern of the cloth, and it will be very noticeable under the paint. Mat on the other hand has fibers meshed in a random pattern. If you do get enough shrinkage to see the weave, the random pattern will be much less noticeable. It won't draw the eye like woven cloth will.
For this repair, I used pieces of fiberglass big enough to cover the whole area. Generally speaking, the bigger the piece you can use, the better. On things like the bottom of the hood with all it's curves big sheets just don't work, but on big flat outer surfaces, they work great. I used an entire 8 sq/ft package of fiberglass mat on just this one layup. This is part of the reason I did all the small spots first, so the top layers of fiberglass could be done in big sheets.
After grinding that down, it was time for the last bit of fiberglass work on the hood. You'll remember from earlier posts that the front lip was pretty cracked up. When I did the back, I ground the lip to a very thin outer shell and layed 'glass in behind it. For the topside, I ground it back until I hit the new 'glass I put in, then layed full length strips across the nose.
With just some more grinding and trimming, that's about it for the fiberglass repairs on the hood. Everything else from here on out is body filler work. Also keep in mind that even though I layed fiberglass over existing paint, it's a huge no-no for finish work. Anyplace there is fiberglass over paint, it's still higher than the finished surface needs to be. Before adding bondo and doing the final bodywork, all the high spots in the fiberglass(where it's overlapping any paint) will be sanded down and ALL of the paint will be sanded off the repair areas. But more on that later...
