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Wednesday, February 15, 2006 12:41:33 PM - Views


VintageWatercooleds.com Technotes :: ATS Technote - Fiberglass Repair

Minding my own business, driving down the Texas highway, a pickup "mud dauber" pickup truck drop a chuck of dried mud, crosses two lanes, I have no way to dodge it, it slams into my spoiler, cracking it badly...

Though this is about my fiberglass Kamei X1 front spoiler, this method of fixing fiberglass can be used on any fiberglass repair you might need to perform on any parts of your body kits.

Here the damage assessment begins, after removing the spoiler from the car, I begin with a 150 grit sandpaper to scrape the top layer of paint and primer to reveal the crack on the front of the spoiler.. its bad..
The crack continues up the euro license plate edge, a single continual crack moving all the way to the stop of the spoiler
Once at the top, the top ridge on both side of the joint have cracked along the edge, fiberglass does not bend very well under stress and this chuck of mud is turning into a nightmare of damage on my spoiler.
the crack finally stops (after hours of sanding, I though I as going to have to toss the spoiler, but it end on the left side (driver side) of the tip edge of the spoiler.
the corner shows secondary damage, a nasty crack, and the bottom angle is totally missing...
here is a complete picture of the damage found...all white lines are sanded areas to the fiberglass to expose the areas that will need to be cared for.
flipping the spoiler on the reverse side, I start working the inside of the fiberglass, sanding it all down revealing the depths of the cracks, and ensuring the best possible "traction" for the new fiberglass Bondo I am about to use to fix it. I used a premixed called Fiberglass Bondo, it is basically a putty of sort that is used for spoiler and fiberglass work on cars and boat, you scoop a lump of it, trickle a little hardener on it, mix and lay on the prepared surface, 5 minutes later its Hot and hard in place as the picture shows, it took 3 lay downs of fiberglass bondo to cover all the areas. I felt it required a thick layer so I did lay about 1/8" thick bondo on the back to hopefully support the damage from re-opening itself.
After letting the fiberglass bondo dry up 24 hours (some people work fiberglass while still warm, I like to work it cold, as the friction of sand paper heats it up as is, and if still warm the fiberglass bondo can become clumpy and detach itself from the fiberglass. here we see I lay a thin layer on the front of the spoiler to a) fill the gap b) to create a layer to hide the cracks.
here is a close up of the work 24 hrs after it dried.
using 150 sandpaper I sand down lumps and edges, then switch to 200 to make it smoother. until the finger tips cannot feel the difference between the actual spoiler and the new material sur imposed on it.
here we see the corner after 200 grit has gone past it.
here we see the reconstructed corner that was snapped off...
while the main breaks dry some more... I start scrutinizing the rest of the spoiler and find some holes on the top corners
some minor cracks on the top right side
a nice hole (was plugged with putty) that needed some attention
Here the top ridge is done... things are starting to take shape.
Finally after it is done, this is what the front of the spoiler looks like....
all area's fixed, I wet sand the complete spoiler with 400 grit to clean it all up, note that there is under layer of paint remaining, it is NOT required to sand the fiberglass back to its original unpainted state to fix it.
right side after 400 wet sand
here the spoiler dries after I wash it with paint thinner to clean out all traces of grease and dust from it. soon the primer is going on it.
fiberglass primer contains a small amount of rubberized compound, this is a good thing for a spoiler, it permits to grip a little more unto the fiberglass, here the picture shows the spoiler painted with 4 layers of primer, work it in light layers to have good coverage, let sit for 10 minutes between each coat the almost dry primer coat will be sticky and help in bounding the next layer unto the spoiler... Then Let dry 1 hour.
a close up of the primed previously broken front license plate area.
close up of the corner that was destroyed and cracked... now doesn't that look good?
once the four coats of primer are dry, I use similar rubberized paint for bumpers, black is my choice of color (and a reason why I used gray primer) 4 coats of paint once again.. in layers, this time 20 minutes apart.. paint take a little longer to become tacky compared to primer that is.
close up of the repainted and finished front euro license plate area
and the corner... its all good now. reinstall the spoiler... enjoy!, I know I did... the complete time frame this took to fix, was 6 days...

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