Body Work & Auto Paint Tips - Get Your Paint On

Here's a nifty trick worth storing away in your noggin. If you narrow a replacement trunk pan before installation, you can position the lip directly over the framerail. Consequently, the seam is undetectable when looking underneath a car on a lift, lending the appearance of original factory metal. Likewise, cutting the trunk pan to the exact size needed, then butt-welding it in place, eliminates any metal that would normally hang down from the seam. "I want my replacement panels to look like factory originals. A lot of people these days have lifts in their home garage, so they're looking at the bottom of their cars as often as the top," Austin explains.

Despite all its benefits, a floorpan is a big honkin' piece of metal and therefore quite a bear to muscle into place. "The average floorpan weighs about 70 pounds, so it's definitely a two-man job and can be a bit of a struggle. The best way to shoehorn it in is through the passenger door," says Austin. "Make sure to remove the doors, steering wheel, and rear quarter glass before wrestling it in. The other option is to go through the windshield frame. This requires removing the steering column and rear seat brace as well, since the floorpan needs to be slid up and past the rear seat area in order to get the front of the pan to clear the firewall."

For those tempted to cheap out, this isn't the place to do it. The upper dash panel on this '67 Camaro is thoroughly rotted out. In fact this area is notorious for rust in Novas and Chevelles too. Anyone with moderate welding skills can replace this piece at home. However, it must be securely welded-not merely riveted-into place. As a section of the car that supports the front windshields, rivets could very well come loose during a collision, sending your glass flying into the air.

Most people have probably forgotten this by now, but many muscle cars weren't equipped with passenger-side rearview mirrors from the factory. This prompted many owners to buy cheap aftermarket pieces, and they often ended up in the wrong location. The prep stage is a perfect opportunity to weld these holes shut and reposition the mirror in the right location. Moreover, all handles, locks, badges, and miscellaneous trim pieces need to be removed as well, as it's impossible to sand around them.

Any time a car has undergone more than one paint job-or has major problems such as chipping, flaking, or cracking-it must be stripped down to bare metal. Failure to do so will compromise the adhesion between the car surface and the paint.

Once a car has been stripped and primered and most of the bodywork has been done, it's time to start fine tuning. Intensive blocking is a staple of any quality restoration. "After a car gets back from media blasting and is down to bare metal, it should be sprayed with a dark-gray epoxy primer to stop rust from forming. You then hit it with a 2K primer and start blocking," Austin explains. "By doing do, any time you see a dark spot it means that you've hit a high spot, which needs to be corrected. Without the epoxy primer base, you'd go straight to bare metal instead. Sometimes high spots are so subtle that you can't even feel them, so this is a great way to verify that the panels are flat. Blocking also removes scratches, pinholes, and other imperfections. This is the stage when low spots should be filled in as well." Block sanding shouldn't be confused with color sanding. It involves sanding down the clearcoat in two-stage paints, and the paint itself in single-stage paints, to remove orange peel, fine scratches, paint runs, and dust nibs. The result is an ultra-smooth finish.

Even with NOS or quality reproduction sheetmetal, there will be a gap somewhere on the car that's too wide despite prodigious alignment efforts. Since epoxy will pop right off, running a bead down the edge of the offending panel with a welder will close the gap right up. Austin prefers setting the gaps at a maximum of 1/4 inch. "The idea is to use a series of spot welds to avoid warping the panel, then filling the rest of the weld in. If you don't, the panel will get too hot and start rolling inward," Austin advises. "Then grind the weld down flat, and repeat the process if necessary. If you get it just right, you won't even need any filler."

The metal surrounding the rear windshield is also prone to rust, especially on vinyl-top cars. Unfortunately, replacement pieces aren't available. After the rusted metal on this Chevelle was cut out, a new metal strip was fabricated and welded in. The roof, on the other hand, was in perfect shape and required no work.

When looking over a potential project car to purchase, keep in mind that any area that collects leaves, dirt, or water is a hotbed for rust. The front windshield support area beneath the molding on this Nova is rotted out and will need to be replaced.

Managing airflow with a paint booth is critical in achieving a consistent paint finish. Poor airflow can cause blisters, since the top of the surface starts drying faster than the paint beneath it, forcing solvents to escape from the paint. Likewise, a proper booth also filters out dust, bugs, and other impurities from the air that could end up on your paint. Laws vary by state, but painting a car outside of a proper booth can result in fines of tens of thousands of dollars. "Either don't do it, or don't get caught," Austin quips.

There are several methods of achieving a slick-looking undercarriage, but one the most effective is spraying it with an epoxy primer. Not only does it leave a nice satin black finish as if the car just rolled out of the factory, but mixing it with a hardener makes it resistant to chipping from road debris. The application is a single-stage procedure, so solvent popping isn't an issue. This particular epoxy is Glasurit Chassis Black.

If you don't have friends you can bum tools off of, tackling a paint-and-body project in your garage is a long-term commitment. The various tools of the trade in this one drawer-hole punchers, grinders, air hammers, drills, air chisels, and so on-costs several thousand dollars. That said, it could take several projects for an investment in tools to pay for itself for a DIYer.