What is the first thing you notice when you see an old car or truck for the first time? If you are like most folks, the answer would likely be the paint. Not just the color but the overall condition of the paint finish. Does it have a beautiful, high-gloss shine or a pleasing, soft “patina” that only the hands of time and exposure to sun and weather can produce? Of course, it is all subjective as we would fully expect a recently completed high-standards restoration to have a flawless, mirror like appearance. Conversely, a car or truck that is 40, 50, 60 years or even older and is still wearing it’s factory applied finish is greatly admired and highly prized for its beauty even though it may be worn through to the primer from many years of being lovingly polished or even proudly displaying some runs or imperfections that it acquired at the hands of that production line painter so many years before.
In fact, at many show events, an unrestored car or truck wearing its original paint will often command much more attention by admirers than a perfectly restored example. What is all the more remarkable when we admire these old, preserved finishes is the fact that those paints weren’t really all that great compared to what is available today. This is not to say that those paints were of inferior quality as the manufacturers generally used the best materials that were available with whatever the coatings technology of the period allowed. It is also important to consider that, as the decades progressed into the 1950’s & 1960’s, the time required to apply paint increasingly became a more critical factor in the assembly of a car and with the exception of some of the more expensive luxury cars, a few flaws such as runs, texture and overspray were considered to be acceptable and actually looked for by some show judging organizations today.
In the early days of the automobile, master furniture and carriage craftsmen painstakingly applied primitive oil-based enamel or varnish primer and finish coatings by brush! These finishes had somewhat poor opacity which required numerous coats for coverage and took weeks to dry. They used mainly ink pigments which all tended to be darker colors. These coatings did not withstand weather and sunlight very well and tended to become dry and brittle before long. Since those paint jobs didn't last all that long, in those days, it was common for an owner to get some paint at a hardware store or mail order catalog like Montgomery Ward along with a good horse hair or hog bristle brush and re-paint the car. With the idea of preserving the car, some folks even did it every year or so…by brush of course!
A number of manufacturers including Ford in the Model T line, used a combination of brushing, dipping and even pouring to fully cover and protect the various parts of a car or truck. The 1920s saw the beginning of the introduction to spray equipment and nitrocellulose lacquers and primers which were developed together to speed application and dry time to a week or less which cut down dramatically the time required to paint a car although they still required labor intensive and time consuming hand rubbing to achieve a shine. This was not especially true in the production of early trucks however, most 1920s to 1960’s trucks were considered to be no-frills pieces of working equipment built to be used and abused, not to be fussed over and pampered. A great example of this is with 1930’s Model AA Ford trucks with that were built with dull, non-shiny, non-rubbed lacquer finishes. Rubbing-out was an extra-cost Ford AA truck option that according to a Ford service letter of 06-05-31; cost $15.00 extra for the cab, cowl and hood while a pickup bed cost $7.00. In addition to reduced dry times, nitrocellulose lacquers were more durable and allowed the use of brighter colored although more expensive pigments. Interestingly, although with constant improvements, the organic-based nitrocellulose lacquer was used by some manufacturers well into the later 1950s when it was replaced with the much more durable acrylic lacquers and primers which were synthetics.
Appearing shortly after nitrocellulose lacquers were enamels or more specifically, alkyd enamels and primers. These were generally a thicker material which required fewer coats than lacquers and usually were baked onto a partially assembled vehicle body by passing it through a large oven. This baking hardens the enamel and “flows” it out for a great shine and greater durability. Many more brilliant colors were available with the enamels which became possible due to the use of organic pigments which were widely popular with some of the more flamboyant and attractive two and tri-toned 1950’s combinations. Eventually, the alkyd enamels too were replaced in the early 1960s by the new and superior acrylic enamels and primers favored by several manufacturers.
Of course as we all know, any paint finish has a limited lifespan and with the harsh conditions it is exposed to, it is remarkable that it can last as long as it does given adequate care. With time and exposure, even the best lacquers will lose their luster, shrink and crack while enamels will fade out and become dull and chalky. These shortcomings and a move toward greater environmental friendliness led to the eventual changeover by most car and truck manufacturers to new base-clear, water-borne systems in the late 1970’s to early 1990s however this period was not without serious issues as many of us will recall the peeling clear coats of many vehicles from that era resulting in scores of cars and truck being repainted through factory warranty claims. Fortunately, the major paint manufactures quickly resolved those problems and the newer finishes are the most durable in history and require virtually no care to survive.
What does this all mean to the owner of a vintage car or truck today who is planning for a paint job in the near future? To begin with, lacquer, while still available, is very difficult to buy today and is actually illegal for sale in certain areas of the country especially California. This is because of state and federally mandated VOC laws. VOC’s are Volatile Organic Compounds which are chemicals found in paints and solvents that are considered harmful to the environment and living creatures. In addition, with the limited life of a lacquer or enamel paint job and the clear superiority of some of the higher quality modern paints, unless you are striving for 100% authenticity on your restoration, it would probably be to your advantage to choose one of the modern alternatives to lacquer or enamel. With today’s modern paints, there are two major choices suitable for use on a vintage vehicle; Single Stage Urethanes also known as Single Stage Urethane Enamels and Two-Stage Urethanes. These urethanes are extremely durable, chip resistant, and chemical resistant and retain their gloss without dulling or fading. The single stage products are only similar to the old air dry lacquers and enamels in that they are one coating with the color, gloss and UV protection all in one material and do not require a clear topcoat. That is, the color is all the way through. They are all 2K formulations which means that an activator must be added per the manufacturer’s instructions which will chemically cure and harden the paint. They can be color sanded and rubbed out to provide that hard to describe yet pleasing, softer “polished bowling ball” look of a genuine lacquer paint job that looks so right on the rounded contours of a restored older car or truck. The two-stage products also known as “base-clear” are also 2K formulations requiring an activator but consist of a thin, no gloss color only film “base” which is sprayed on then top coated with multiple coats of urethane clear. The clear is then responsible for all the UV resistance, gloss and protection of the paint coating. While the two stage base clears do provide an attractive, deep, high gloss finish on more modern vehicles and the clear can also be color sanded and buffed to a glass-like surface, they often can be too glossy and look out of place on an older car.
Another two-stage, base-clear system is the “water-based” coatings that are rapidly growing in popularity especially in today’s VOC sensitive world. It should be noted however that it is only the color base coat that is water based. At this time, there are no known, successful water-based clear coats. They are still solvent based formulations although the paint manufacturers are working hard to introduce successful, water based clear product.Click Here To Read Full Post...