Need advice on fiberglass repair. Racecar got a bump. (Pics and video too.)

[cstreit]

Just got back from the Road America Vintage Fest. Pictures and video here...

Unfortunately I have some fiberglass repair to do...

Does this look fixable?

ELVF Pictures, Video(!) and story (Racecar gets a bruise)

What would be the best method, ste-by-step, I'm not that experienced with 'glass and have only done small projects.

(The video does not show the impact)

Thanks...

[TC 911]

I worked in the composite shop of an airine in my previous job. It has been several years but I would be glad to walk you through it. Unfortunately I can't access the link. I am better with 'glass than computers. Please post a photo.

[cstreit]

Pic:

[Early_S_Man]

Chris,

Sorry to hear about the 'crunching.' Glad it wasn't worse!!!

Dfinitely fixable, though I wouldn't attempt the repair on the car! Patched-up ... nobody will be able to tell it was ever hit!

[Vintage911Racer]

Chris,
How does your club look at an incident like that? With VARA the group I race with, it is the overtaking cars responsibility to make a clean and "safe" pass. You said you had overtaken a back marker but your left front hit his right rear you had not overtaken him yet. Our club says if your front tire is passed the "A" pillar of the car you are trying to pass then the pass has been made and any contact would be the fault of the other driver. How did they rule in your incident? "racing incident"???

Sorry about the car. I just had to do the same repairs to mine. I too was lapping a back marker for the 3rd time. There were 5 of us battling for the lead. We came up on the back marker, he moved over for the first 3 cars then decided taht was enough and came back into the racing line. Unfortunately I was right there. Fiberglass damage, messed up my new paint, broke A-Arm, broke Brake line, bent strut, bent steering shaft (from the rack up was bent). I have since gotten her fixed and will be racing at Buttonwillow Raceway in California this weekend.

Your car is very easily fixable.

[cstreit]

I'm lucky and only the 'glass was damaged, no structural elements (save a slight bend in the bumber monting bracket. The 'glass on the car is VERY thick as it turns out... SO much the better for me in this case.

I already have the fender off and intend to clean up the edges a bit, lay glass/resin in the back, and then fill the crack in. Will sand and only spot/feather in some paint for the remaining two events.

This winter I am probably going to get 'glass doors and hood anyway, so the whole front of the car will be re-sprayed... (Doors, fenders that need repair, bumper, hood)

[jpnovak]

Chris that's an easy fix. Fiberglass is very forgiving to work with. Here's what I would do.

First, cut back the damage so the opening is about 1/2-3/4" wide. then sand the edges of the damage with 40-60 grit so that its a bit roughened and the paint is removed about 1.5 inches from cut lines. also do the back side. cut a piece of plywood that is near the shape of the headlight bucket(flat). PUt the fender in shape and screw the wood to the front of the headlight flat. use at least 3 screws/side. You can use clecos if you have them, Nuts and bolts also work.

Get some Polyester resin and 6-8 oz. fiberglass cloth. Cut cloth in strips that are an inch wider than the damage. Mix resin according to the directions. Don't use too much hardener. Wet the cloth with some resin. My favorite method is a flat piece of wood. Lay out the cloth and pour resin on it. then pick up the now wet cloth and lay up across the damage from the back side. use a special roller (marine supply) or a disposable paint brush to lay in more resin and remove air bubbles. Make sure to remove air bubbles as it will affect strength. Use three layers of glass here. While its wet, smooth any edges with the brush or roller. Let cure.

Now the fender is structurally sound, its time to make it pretty. remove screwed on piece of wood. get some chopped cloth(sometimes called kitty hair) or pull apart cloth from above. Mix the resin and wet now separated cloth. Lay into damage and low spots on the front side. This is where you will need to be really smooth in layup. The roller may work better than the brush. let cure. keep building up low spots until nearly smooth and a slight bit high.

Sand flat. Use a touch of body filler to finish. Block sand, prime and paint.

I just used this method to close up my gas filler door as I install a hood fill. Good luck. Don't forget the respirator when laying cloth and the dust mask when sanding.

[TC 911]

Definitely repairable. I just wanted to add to some of the great information you already received.

Clean out and chase all of the cracks to keep them from coninuing. If you have not tried to perform a fiberglass repair with a vacuum bag, I highly recommend it. It allows the most novice to make strong and professional looking repair.

Clean out all the loose and broken glass. Sand back the paint for a good bond as described by jpnovak. Try to avoid using glass filler. It comes in strands like hair to very fine powder like a baking flower. They make a good filler, but woven cloth will give a stronger repair if is used as a filler in layers. Fillers are good for a non structual void that you want to fill then glass over.

I prefer to repair one side at a time. Apply a wood, metal or plastic baking as described by jpnovak. Use a release cloth or agent (plastric wrap) to keep it from sticking. Do not use oil or cooking spray that can contaminiate the repair.

Buid up your layers of cloth. Firrst cut strips just larger than the size of the repair. Build up the layers to fill in the voids. Cut each layered strip wider until it overlaps the repair area. Saturate each layer and chase the bubbles before applying the next layer.

Do not over saturate the cloth. Just enough resin until the cloth goes clear.

Cut a piece of release cloth that covers the entire repair area. Lay it over the repair. Ther is no need to roll it out or chase air bubbles. You can add more layers of release cloth to wick up the extra resign.

You will need to seal both sides of the repair area. Use the sealing putty (similar to plumbing putty) to roll out a bead around the perimeter of the repair area. Cut the vacuum bag plastic material larger than the repair Lay the sealing plastic over the repair and use your fingers to seal the bag against putty.

Cut a small slit in the sealing bag and insert the vacuum valve. It is a small two piece metal valve that you hook you compresor air line to.

Hook up the compresor line to the valve. Use you hands the manipulate the plastic bag so that there are no creases in the bag on top of the repair area.

The vacuum will pull the bag tight against the repair and squeeze out any voids or air bubbles in the glass repair. It also compresses the extra resign out of the glass and into the release cloth.

Allow to dry or add a heat lamp to hurry it along. Repeat on other side. The vacuum bag will make a very prefesional repair on flat surfaces and curves.

All of the above materials are available in boart repair type shops.

A few tips:

Use coarse cloth on back side of the repair. It is strong, cheap and ugly.

Most resins are measured by weight not volume. Double check, then follow the directions on the can.

Most people use too much resin. The strength is in the cloth.

Some resins can heat up noticeabley and give off a vapor when curing. Work in a well ventilated area.

Always wear a mask when working with fiberglass.

Use a shop vac by your work when sanding.

I hope this helps. You can use the same process for carbon fiber repairs.

[pu911]

Chris,
Ouch, still headed to mid-ohio. I have some extra f/g parts around (in AZ) if that helps.
Phil

[cstreit]

Phil, Definitely. THis will be fixed by next weekends event.

Thanks for the tips TC and JP, I'll post some results when I finish this weekend!

Chris

[thrown_hammer]

Glad your okay. This is just another reason Road America scares the crap outta me!

[RickM]

TC...you wouldn't happen to have any pics of this procedure would you? I'd really like to see the plastic bag/valve in action. I need to repait my FG air dam and this sounds ideal..... Great thread!

[TC 911]

Rick, I'm sorry I do not have pics. I had the luxury of learning and working in the well equiped composite shop of United Airlines. I have not had the need yet to do any fiberglass repairs at home. The materials are inexpensive and available at fiberglass repair supply companies (boats).