Restoration
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CARB
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.

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Photo Guide

Prior to starting any bodywork, you can save money by stripping all the exterior trim from the car. All front-end trim, door handles, wheel well trim, and other brightwork have been removed and can be detailed at home while the car is in the body shop.

We used a disposable brush to apply the stripper in even, unidirectional coats. Cross-brushing will pull the stripper off, defeating the purpose. Let the stripper sit on the surface for 8-15 minutes and work in controllable areas of the surface. You don't want this stuff to run uncontrolled.

After plenty of time and patience, the original sheetmetal is peeping through. If you live in a damp climate, primer must be applied immediately after stripping a section to prevent surface rust from starting.

After stripping the front fender, we found a patch of old body filler. It must be removed to ensure a quality repair. We have no idea how deep the damage is, so it will be ground out completely.

Using the grinder and a 36-grit disc, we cut away the old material. Holding the grinder parallel to the surface prevents the wheel from doing any additional metal damage. Slowly grind down the filler, inspecting the area as you go. We found that much more filler was used to repair this dent than was needed.

A body hammer (drift) is locked to the brass nail, and the area is gradually pulled out toward its original shape. Treat this original process gently?use the drift to get as close to the original contour as possible. Then apply the minimum possible amount of Bondo, essentially just to smooth over the straightened metal.

To eliminate any high spots, gently tap the area with a flat-head body hammer. This will bring the metal into a surface conformity (shop slang for "as smooth as possible") prior to adding the body filler or Bondo.

A light coat of sanding primer is applied over the filler only and allowed to dry. Any pinholes or imperfections in the filler will now appear and can be filled with polyester glazing putty. After any remaining repairs are made and each individual area is sanded smooth, a coat of the working primer is applied over that area. This protects the bare metal from moisture while you work on other portions of the car.

The Goat doesn't look so tough without its coat, does it? This street-raced menace is ready for a new wardrobe. Inspect each panel and then grind the previously repaired areas clean of primer. They need to be readied for a full coat of self-etching primer.

Once all the panels are smooth and clean, it's time to apply the non-sanding metal-etching primer. The preparation for this step may not make sense right off, so bear with us. First, hit the metal surface with 80-grit paper on the sander to apply a good texture for the primer to grab.

The area is now wiped down with metal prep and blown dry to remove any particles left by the grinding process. Whenever dealing with metal or grinding debris, wear nose and eye protection.

Now things get weird. Thoroughly scrub the area with a kitchen cleanser such as Ajax on a wet scrubbing pad. We know what you're thinking: rust! However, plenty of cleanser and water will remove any oil spray and leftoever residue from the grinder and your hands. Take particular care in small detail areas like the trunk lock hole.

After the deck lid has been completely scrubbed, it is washed down with clean water to remove the soap residue. Starting at the highest point, water is worked into the surface to remove all soap. Remember, you've pulled out all the weather stripping, so you don't want Niagara Falls here. If possible, use compressed air to blow-dry all of the cracks.

Before cleaning the bare metal with surface prep, carefully read the instructions on the bottle. All of the products should come with complete instructions printed on the container. A bathing coat of surface prep is applied with a clean, soft cloth and wiped until dry. This is the final treatment prior to squirting on the self-etching primer.

Each work area is masked off individually if the surrounding areas have not yet been prepared for the self-etch primer so that the primer won't chew into unprepared metal. Be thorough and exacting while masking off the car?loose spray will get through wherever it can.

A metal mixing stick is an indispendable tool for mixing today's paints. Incorrect amounts of material can lead to disastrous results: paint that doesn't dry, falls off or hardens prematurely in the gun. This mix is two parts primer, one part hardener. When the hardener is added, the marker should show material to the 3-.

The primer is applied with a low-pressure/high-volume gravity-feed spray gun. Light and even passes are the best, allowing 10 minutes between coats for the prior to set up. Three coats are usually sufficient to completely cover the metal.

The GTO's body is now washed, scrubbed and squirted with a full coat of self-etching primer. The primer lays down smooth, has a nice workable sheen and seals the surface from moisture.

A dusting of black paint, called the guide coat, is applied over the entire surface of the GTO. Use a very light spray. It's called the "lie detector" because a light sanding will leave definitive black trace paint where the metal is deformed.

Standing flat with an 80-grit paper longboard will find any low spots in the metal. The dusting coat will remain in the low areas while they grey primer will surface through the guide coat. Here you see a large but shallow depression that we will fill. Additional sanding indicated two depressions instead of one.

Several light coats of primer are applied over the repaired area, and the rest of the rear quarter is now cleaned and sanded clear of the guide coat. The repaired area will be sanded again once any other damage is fixed. The whole quarter is now sanded, and other areas that need attention are detected.

We hope your work comes out as straight as an arrow and ready for long-board action. The rest of the body needs to receive the same treatment and attention.



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