I often field questions regarding the various types of automotive paint available and what types are best. There's no one answer that covers every situation rather answers or suggestions that are dependent on each situation in a refinishing job. There are many factors that go into choosing which is the best type of paint for your needs but final appearance, ease of use, cost, and durability are the biggest factors most consider. If we focus on these considerations and walk you through the process hopefully we will have helped you make the right decision for your situation.
To Prime or Not to Prime?
The short answer to this question is always use the proper primer system whenever you can afford to do so. Most car owners are unaware of the process of finishing a car to a "class A" finish. The first step to ensuring a quality paint job that lasts is the proper selection and use of a primer. Primer is a broad category encompassing anti-corrosive primers which prevent metal surfaces from corroding, primer surfacers which fill small dings, dents and scratches, primer sealers which seal off undercoats in preparation for applying color coats, and adhesion primers whose primary function is to ensure adhesion to a particular surface. This may seem overwhelming to the beginner but bear in mind that not all of those types of primers are always required and many primer products will function in multiple roles. We'll give more detail on which primers are best in our next section. If you are on a really tight budget and your paint is in pretty good condition (no cracking, peeling, severe gloss loss, fading etc) then primer may not be necessary. However, you should check with the manufacturer of the paint brand you select to confirm they recommend use without a primer.
What kind of primer should I buy?
As we discussed in the previous section there are a lot of primer options available. Choosing the right primer is depends on the condition of your vehicle but we'll do our best to distill it down to a few of the best options. If you have any bare metal on your vehicle we strongly recommend a 2K (2 part) epoxy primer. Epoxy primer is the best for adhesion to metal and providing corrosion resistance. It's likely you don't have bare metal on your car to begin with but part of the refinishing process typically would involve sanding areas smooth and applying body filler as needed which will likely expose some bare metal. Often only a quart or two is needed to spot prime areas where bare metal is exposed. However, serious restoration projects often involve priming the entire vehicle with epoxy primer as added insurance for corrosion resistance and adhesion. On areas where there is a lot of small dings, scratches or body filler it's a good idea to use a 2K (two part) urethane primer surfacer. Urethane primers typically offer better filling and sanding than epoxy primer so a combination of epoxy primer for the adhesion and corrosion to metal followed by a good urethane primer for filling and sanding is the perfect "one two punch" for preparing your vehicle for painting. If your vehicle is in pretty good shape already, (meaning it doesn't have a lot of dings, scratches, flaking etc), a 2K urethane sealer is a great option for providing a good foundation for your color coats. Some paint manufacturers offer urethane sealer in a wide range of colors so you can match the color of your primer closer to the color of your final finish. Matching the color of your primer closer to the color of your final finish reduces the amount of color coats (usually the most expensive part) needed and when those inevitable stone chips or scratches happen they are less visible over a color keyed primer than over just a typical grey primer in most cases. For primer selection we generally recommend avoiding lacquer type primers, aerosol or spray bomb primers, and enamel primers due to potential issues with recoatability, and durability long term.
What kind of color coat should I use?
There are a lot of color coat options available to auto paint refinishers today with varying performance and costs. Knowing the durability, appearance performance, and general cost of these various types of product I would highly recommend either purchasing a 2K (2 part) urethane single stage topcoat or, preferentially, a urethane basecoat/clearcoat system. A urethane single stage is a product that provides both the color of your finish and the gloss sheen in one product while a basecoat/clearcoat system consists of a color layer (the basecoat) and an additional layer (called clearcoat) to provide the final gloss appearance. It may appear the urethane single stage is the obvious route because it requires only one product to achieve both gloss and color, however, despite the added cost and extra steps, a vast majority of all cars rolling off assembly lines today are painted with a basecoat/clearcoat process. Basecoat/Clearcoat offers enhanced metallic and pearlescent application and effect and generally last longer than single stage finishes. Early in the finish life cycle basecoat/clearcoat and single stage finishes may have similar appearance but as time goes on the basecoat/clearcoat finish will require less maintenance (ie waxing and detailing) to maintain the high gloss finish. Costs are higher for a base/clear system versus a single stage system but the overall service life improvements will reduce maintenance cost and likely preserve a greater resale value for your vehicle. Savvy shoppers are finding deals online for basecoar/clearcoat kits that are comparable or even less in cost than many single stage finishes.