How to fill many 2.5" "speed holes" in my IROC FB body work

[MarkRobinson]

someone when nuts at Valkyrie & drilled out 20-30 2.5" holes in the front/rear bumper body work: drives me nuts.

How do I fill these holes? Do I need to purchased a compatible flat product (Recommendations) and a 2.5" drill/hole bit? Fill from the backside with resin/matt?

Thanks for any suggestions...compatible FB materials available at sheet-plastic supply store recommendations too.

Mark

[drcoastline]

Mark that is a simple fix.

Use a grinder with a sanding disk or a drill with a rotolock sanding disk attached and feather the edges around the holes. 80, 100 grit will do the trick.

Cut a piece of cardboard, luan, a plastic real estate sign from the neighbors yard. Anything rigid to fit inside the cavity of the bumpers. It doesn't need to be perfect. just so it lays flat and snug. Next wrap the backer with a piece of plastic drop cloth. (the plastic sign board will not need to be wrapped). Place back in the cavity.

Next cut several layers of glass mat to fit the feathered hole. The first layer should overlap onto the original fiber glass at least 1/4". Make each layer slightly smaller than the last until they build up just proud of the finished bumper. Judging from the photos this should only take about three or four layers of mat.

Mix some fiberglass resin (available at the big box hardware stores) according to directions.

Brush some resin mixture on the backing and onto the feathered edge of the holes to be filled with a throw away chip brush.

Next lay the largest layer of mat in the feathered opening. Wet the mat with the resin until transparent.

You will find it easier to squish the resin in and dab the bristles straight down vs. brushing.

Continue to lay in each progressively smaller layer and wet out until transparent.

Work wetted mat to remove air bubbles. If you do not have a fiberglass roller to remove air bubbles Your wifes still bristle hair dryer brush will work. Just don't tell her I told you to use it. Work the bristles back and forth gently until the bubbles dissipate. You can also use a stainless steel brush and/or dab with a chip brush.

When resin has hardened remove the backer and plastic.

Sand to shape. Use body filler where necessary, prime and paint.

Good luck with your project.

[MarkRobinson]

Ok I can do that. not a simple fix but still cheaper than new bumpers + shipping(s).

So the new FB won't stick to a plastic drop cloth??

Thanks!

[drcoastline]

Correct. You can even try an old piece of tupperware, plastic lid, section of a plastic 5 gal. bucket, etc. Cut it to fit and duck tape it in place to hold it still.