Special Report Insight& Reviews From Larry

October 1, 2010 | By Larry Lyles

Readers Ask This Restoration Pro About Painting & Fiberglass, And He Tries a Sound Damper and Rust Remover.

You Have to Find and Repair All of the Fiberglass Cracks

I am working on an old fiberglass car. I have stripped all of the old paint and found many spider cracks on the surface. How do I prep these cracks before applying primer to the car?

Jim Lichter Via e-mail

Those cracks are in the gel coat of the fiberglass and will need to be repaired before you apply any primer to the car. The first step is to find and mark all of the cracks as any crack you miss will show up once you paint the car.

After locating all of the cracks, begin repair by cutting a “V” along each crack. You can use a die grinder with a 3-inch cut-off wheel to cut the Vs to open up the numerous cracks.

Fill each of the cuts using Evercoat #473. This is a heavy body fiberglass gel product that will fill the cuts and give you a solid repair.

Sand the gel with 40-grit sandpaper and apply any necessary body filler over the repairs.

How do you find all of the cracks? Try 3M Dry Guide Coat #5681 to highlight the cracks.

Can I Safely Spray Paint… In My Garage?

I’m doing a frame-off restoration on a 1958 Buick Estate Wagon and am thinking about spraying the epoxy coat on the car. I’ve acquired all of the necessary equipment and safety tools, and have a two-bay garage. Would it be safe to use this area for painting as long as I turn off the furnace to avoid a source of ignition from the fumes?

Michael Edmonton, Alberta

You can, but unless the paint fumes are controlled they will seep into the house and that could be dangerous. I recommend constructing a portable spray booth like the one I constructed in the December 2006 issue. This unit consists of a PVC pipe frame and is covered with heavy plastic. The design allows you to vent the paint fumes to the outside and would make your garage much safer for spraying.

Advice On Products and Techniques for Painting a Vehicle

In your book, “Project Charger,” you used DuPont refinishing products. I’m going to follow your instructions, but instead of using DuPont I’m going to spray House of Kolor paints.My question concerns how much material I will need.

I’ve already finished the underside of my 1970 Charger with Eastwood Chassis Black and do not plan to spray the inside of the car. The car also has a vinyl top so I’m thinking I might not paint underneath the new top.

Thanks for your help and might I suggest an article or book covering the art and science of painting a car? Hint…hint.

Scott Checkeye Harwick, Pennsylvania

I used HOK (House of Kolor) products on Project ’46 (the book compilation of the Auto Restorer restoration series is called “Project Street Rod”). You will find some good information on the HOK brand in that book.

To be sure I have this straight, the plan is to paint the exterior of the car plusthe engine compartment. You stated in your letter (an edited version appeared here) that you used HOK CP2CF primer on the car to do the block sanding work and the car is now ready for paint.

The products you will need are:

KO Seal II white—1 Qt. Mixes at 4:1:1 with KU 150 hardener and RU 311 reducer.

PBC 64 Base Coat Orange Pearl—4 Qts. Mixes at 2:1 with RU 311 reducer.

UC 35 Clear—4 Qts. Mixes at 2:1:1 with KU 150 hardener and RU 311 reducer.

KU 150 hardener—2 Qts.

RU 311 Reducer—6 Qts.

I’m overestimating the amount of base coat due to the fact that this is a pearl color. Most pearl colors are extremely transparent. HOK tech sheets indicate PBC 64 can be sprayed over KO Sealer White for a lighter finish.

My recommendation is to use a small amount of the PBC base coat and spray a coupleof test panels to get a feel for how this color lays down. Watch for streaking and mottling and be very careful to maintain the same air pressure, spray gun distance, and number of coats with each panel you spray.

Also, if the new top isn’t already on the car you can skip applying base color to the roof panel. Just cover the old finish with 2 coats of clear and install the new top.

Asfor more art and science behind the spray gun…I do get a ton of questions about painting, that despite four books and countless articles on the subject already. I’ll continue to write more articles on the subject so stay tuned. I am currently working on a new set of DVDs and these do concentrate on repairing and refinishing a complete vehicle.

Editor’s note: For more on Larry’s restoration books and DVDs, visit his Web site, lplbodyworks.com.

Some Primer/ Surfacer & Plastic Bumper Advice

My son and I are restoring a 1969 GTO. I will be applying PPG base coat/clear coat once the car is ready for paint. At this point the car has been sanded down to the bare metal. Do I need to apply an etching primer before doing the plastic body repair work?

Eric Lund Via e-mail

Forget the etching primer. Newer Model vehicles have metal treatments designed to prevent rusting and most of those vehicles need an etching primer before doing any paint work on the car. Your vintage ride was made of mild steel in an earlier era.

My recommendation is to apply two coats of epoxy primer to the body, do any needed plastic body filler repair work, apply two more coats of epoxy, followed by four coats of urethane primer/surfacer.

Follow This method and you will end up with a bulletproof substrate over which you can apply the base coat/clear coat finish.

By the way,your supplier probably will try to sell you a flex additive to add to the paint once you are ready to paint the Endura bumper. (Fornon-GTO lovers, this car has a plastic-coated bumper.) Forget the flex additive and treat the bumper the same as you would the rest of the car, epoxy first, urethane primer/surfacer next,then base coat/clear coat. Why no flex additive? Flex Additives are meant for use on extremely flexible bumpers and only work for a few hours, just long enough for you to mount the bumper. After that, the paint cures out and the additive dissipates

Got dings in the Endura bumper? Use a 3M #5895 EZ Sand Flexible Parts Repair Kit to make those repairs.

Editor’s note: For more on repairing plastic bumpers,see Larry’s two-part series in the May-June issues.

And Now, It’s Time for a Few Product Reviews

Rumble Mat Sound Deadener

I’ve reached the point where I rarely build a car that doesn’t have some form of sound damping insulation added to it. It only makes sense because old cars just weren’t constructed to roll silently down the road. To that end I’ve tried another sound deadening product called Rumble Mat.

Rumble Mat may look like some of the other sound deadening products out there but there is a huge difference. Rumble Mat is thicker, measuring a full .070-inches, which gives you more dampening material for the money. It is extremely flexible, which makes it easy to install. It comes with an aluminum covering on one side and very strong adhesive backing on the other side. Once it is stuck, it is there and it is tough enough that you can’t tear it.

RumbleMat is available in door kits, to make life easier insulating the inner door panels, and in 25- and 50-square foot rolls to cover those large jobs from top to bottom.Best of all,Rumble Mat is affordable. I take that into consideration every time I budget a project. (Prices listed on the Rumble Mat Web site are a 12.5 sq. ft. door kit, $59.99; 25 sq. ft. [18.75 ft. x 18 in.], $109.99; and 50 sq. ft. [33.3 ft. x 18 in.], $189.99.)

For more on Rumble Mat:

Rumble Mat

4960 Iroquois Ave., Erie, PA 16511


Metal Rescue Rust Remover

One of the most difficult aspects of automobile restoration is getting rid of all of the rust. Where large parts are concerned we can have them media blasted to remove rust. That part is easy. The real problem comes when you need to remove rust from all those small parts without damaging them. That’s where Metal Rescue comes in.

Metal Rescue is a liquid rust remover designed specifically for removing rust from the smaller metal components on your project.

All you need to do is remove the dirt and oil from the part, pour Metal Rescue into an open container and immerse the part. Getting rid of the rust takes from 10 minutes to 24 hours, depending upon the part and how heavily it is rusted. (The manufacturer says that Metal Rescue removes the rust on parts with a water based, synthetic molecule that is attracted specifically to iron oxide (i.e.rust). Metal Rescue removes the iron oxide and holds it in solution, leaving the base part and other materials unaffected.)

Metal Rescue works on iron and steel as well as aluminum and chrome and other metals. It is also safe to use if the part has rubber, plastic or glass attached to it.

Metal Rescue is non-corrosive, nonflammable, non-toxic, biodegradable, and contains no Volatile Organic Compounds(VOC). That makes it safe to use in just about any environment.

Metal Rescue is currently being rolled out nationwide but if you can’t find it locally try: metalrescue.com. Prices listed on the company Web site are: Quart, $12; Gallon, $25; 5 Gallons, $90.

Armor Protective Packaging

951 Jones St., Howell, MI 48843