Car Paint Preparation | Deliver your car to the bodyshop half-finished.

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Whether amateur or pro, few collector-car restorers paint their own vehicles. Paint is so important to the overall visual impact of the car that it's usually better left to the pros. Here we'll show you the proper way to prepare a collector car for a show-quality paint job, detailing the materials used and providing some hints on how the pros do such a good job.

Material Info
The first rule of thumb for a trouble-free paint job is to use the same brand of paint and paint products throughout the entire process. Never mix brands or your paint might literally fall off the surface of the vehicle.

Most automotive paint manufacturers have color-matching tables and computers that quickly match old colors to today's new high-tech paints. Consult the manufacturer one-on-one for each exact painting situation because conditions are never the same from car to car—let the experts call the match. Since we are using a metallic paint (1970 GM Lucerne Blue), we must use a basecoat/clearcoat urethane combination. For non-metallic finishes, a single-stage urethane paint may be used.

All the paint products we'll use on the GTO here are urethane-based and fired by adding catalyst. Numerous prep chemicals and materials will be used in the painting process. We'll need a low-volatile organic compound (VOC) metal cleaner. It's used on bare metal surfaces to remove any oils or other contamination just prior to priming the area. Coated-abrasive 24-grit sanding discs are used to grind out any body fillers or other materials found on the metal surface. When used with a 5-inch grinder or dual-action (D-A) sander, they save hours of hand-sanding.

Polyester glazing putty with catalyst is used to fill small surface imperfections and dings. This putty is a skin-filler only and can't take the place of Bondo for large repairs. A non-sanding, self-etching primer will be used with a hardener on bare metal to etch into the surface for a secure, rust-preventative bond. A working primer and its urethane hardener are used over the surface of the self-etching primer to finish the bodywork and to ready it for the final block-sanding. You don't need to sand the self-etching primer before applying the working primer.

Illegal Lacquer
In California and an increasing number of other states, lacquer paint is no longer legal because of the contaminants it releases into the atmosphere. Most areas of the country will soon implement the same restrictions to ensure clean air and reduce airborne pollution as the EPA's plan to achieve "national ambient air-quality standards" for all 50 states. The paint police have imposed strict regulations on paint manufacturers and body shops to comply with VOC restrictions.

The California Clean Air Resources Board (CARB) is the enforcer of the VOC regulations, and each bodyshop is required to record the amount of materials used each day in a logbook. The book is periodically checked by CARB and, if the shop doesn't stay in compliance, serious sanctions and fines can be levied against the owner. Therefore, it's in everyone's best interest to be concerned with air quality, particularly since you can get a fabulous finish with today's paint technology while remaining within clean-air standards.

Two-stage (or basecoat/clearcoat) urethane products are used as excellent alternatives to lacquer. Actually, these urethane materials are tougher than the old lacquers and produce outstanding and long-lasting results. This system gives an almost bulletproof surface that will shine for years with a little care.

Earthquake Damage
The vehicle shown here is a 1970 GTO convertible which has passed through a series of owners. It had three primer-to-color repaints over the original factory lacquer. Three repaints leave a lot of material build-up on the surface, which can result in surface cracking. This car's paint looked like splintered safety glass.

To add to the crunchy surface-level cracks, this poor "Goat" lived near the '94 Northridge Earthquake epicenter and was showered with garage-shelf stuff when things got shaky. It was peppered with small dents and dings, so we decided to do the job right and strip it to the sheetmetal. Word to the wise: If you live in earthquake country, use positive-locking mechanisms on all garage-cabinet doors and make sure to anchor the cabinets themselves to wall studs.

How Deep?
After a complete examination, our bodyman recommended stripping the surface to the metal to remove all contaminants in the old paints. It's a lot of handwork, but this ensures against the old paint surfacing through the new materials. Chemicals used in older paints can linger in trace amounts. Going to the metal also allows you to fix dings and dents by working the metal itself, not via body filler. Another reason to remove all the paint is to regain sharp body lines and edges that several layers of respray have rounded off.

Prep Tips
Here are a few tips for the beginner who needs to be a part of the process as well as for the stubborn do-it-yourselfer who wants to save every thin dime. We hope these hints will save you time, money, and cursing.

TIP 1: One of the main things to remember is the importance of physical protection during the job. Particle masks are cheap insurance for your lungs while sanding, rubber gloves will protect against chemical absorption through the skin, and a respirator and disposable paint suit will protect you while spraying the primer.

TIP 2: With the exception of fiberglass-bodied cars, the make, size, or model of the vehicle makes no difference—the preparation of the body and application of products is the same for a car, truck or lawnmower.

TIP 3: While doing bodywork on a vehicle with a vinyl roof or convertible top, always completely seal these areas with masking paper before starting. Fine sanding dust and primer overspray can ruin the surface of your top. A few minutes of precaution can save big money later.

TIP 4: If you're working with body filler that needs to be shaped, try a "cheese grater." This is a small file that looks like a regular kitchen cheese grater, and it makes short work of cutting hard Bondo for preliminary shaping.

TIP 5: Whenever working around tires and wheelwells, use a plastic trash bag over the tire to prevent overspray on the rubber. Overspray is a pain to clean off, and a 30-gallon bag will easily fit over the tire and wheel.

TIP 6: After you think you've found all the little dings in the paint, apply a dusting "guide coat" of black paint over the primer then block-sand the area. Any small indentations will retain the black dusting and immediately show up.

TIP 7: When using today's catalyst paints, always read and follow the mixing instructions to the letter. A paint measuring stick is a must-have item—incorrect mixing can cause frustrating problems. Don't forget about staying true to one paint manufacturer. We can't stress enough how bad it is to cross brands.

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