Posted by Reid Welch on July 21, 2000 at 02:47:16:

Excerpted from a painting article originally printed Coopers Vehicle Journal, London. And reprinted in the January, 1926 issue of The Automobile Trimmer and Painter, from which the following text was taken. For easier reading by denizens of the US some of the British words have been altered to reflect American habits. Also, some phrases have been changed for better clarity. The style of coach painting described below cannot be called a standard method, being described as it was by a writer, not a painter. However, it illustrates typical shop practices at a time when spray equipment was still in its infancy, and sprayable paints primitive indeed. Wet/dry sandpaper had not been introduced. Nor was masking tape, as we know it, yet invented.

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Before dealing with the methods of painting, it would be well to examine the article which has to be painted. In this way it is easier to understand the purpose of painting. An automobile consist of a chassis, body, fender and metal splash aprons. The chassis being of steel, and the body of wood with metal panels. Few bodies today are built with mahogany panels and this in itself perhaps accounts for the various methods adopted at the present time for coach painting. When discussing the question of painting with a customer the coachbuilder invariably suggests the following method to obtain the best results, but unfortunately, this is seldom approved by the customer, owing to the extra time taken. The customer generally wants all that is suggested but cannot wait for it to be done.

The Old and Original Method

The body in preparation for painting must be quite free from rust, grease or other foreign matter. It is therefore essential to see that the body is dusted inside and out and, if required, the panels sandpapered and prepared ready for a priming coat. The priming coat consists of genuine white lead with raw linseed oil, patent dryers, and a little vegetable black, to give the desired gray color, and thinned with turpentine for use. The body, both inside and out, is given one coat of this paint, applied thinly and evenly, and worked in with the brush and allowed twenty-four hours to dry. The second coat of priming should then be applied, and in some cases, a third is required. After this procedure, some painters prefer to putty up the bad places, whereas other prefer to carry out the surfacing-filler first. This is a question which is left entirely to the painter. In other words, it is one of the parts of his method. The number of coats of filler to be applied depends entirely upon the class of work, three or four coats for general standard work and anything up to seven for high class work with mahogany panels. The filling-up process, allowing for time to dry usually takes at least one week, allowing a day between each coat to dry. When the final coat of filler is dry, it is necessary to putty up the various screw head, pin holes, etc. The putty usually consisting of dry white lead, japan gold size and, in some cases a little turpentine and tub lead to harden the putty. The body is now ready for a staining coat or guide coat, generally a black coat of paint consisting of lamp black, turps nd gold size. The next operation of rubbing down is a very tedious one, and yet a very important one, as any careless treatment will necessarily scratch and score the panel and entail a lot of extra time and work making good the defect so caused. Prepared pumice blocks are usually used for this work, together with a sponge, wash leather and sash tool. There are two methods of rubbing down- either the dry or wet method, and this again is left to the discretion of the painter. This having been done successfully, a perfectly smooth surface is obtained, the grain of the wood, etc,. bign properly filled up, and the body is ready for painting.. Another coat of lead color, similar to that already mentioned is now applied, and this has to be leveled down. After the rubbing down process it may be found necessary to use a little more hard putty to fill up further imperfections which may have been discovered. Feeling sure that everything is quite in order, the painter now proceeds with the color.

Color Application

A coat of ground color or common color, as it is termed, is applied. The number of coats of the color in turps generally depends on the nature of the color, and also the final color desired. These coats dry flat, being principally pigment in a bare minimum of oil. Assume one coat of common color, the painter will then follow on with two coats of the best color and two coats of japan color; if it is a limousine or brougham with top quarter, allowing a day between each coat. He will then follow on with a coat of varnish color or glaze as it is called, which, when perfectly dry and hard has to be leveled down. The operation of leveling usually consists of either pumice on a wetted felt block, or in some cases, cuttlefish is used for this purpose. The flatting process is a very tedious job, and has to be done with great care to avoid cutting through the color, or making it patchy appearing in the case of light or delicate tints. This work of flatting calls for a fair amount of skill, as well as patience. The painter has now a very smooth surface, made much more attractive than when first rubbed down after being filled up, because tof the number of coats of color which have been added. Now, the final and most difficult part of the painting operation has to be performed., viz., that of varnishing. When the body is dry the painter applies a coat of hard drying or rubbing varnish as sit is called. This has to be flatted down as previously mentioned, and the pinstriping has to be done after the final flatting. The body is now ready for its coat of finishing varnish. This should be applied under ideal conditions of cleanliness and temperature.

The Test of a Painter

It is this application of the final coat of varnish that puts the painter in the leading rank of craftsmen. No amount of technical training or theoretical work can equip him for this job. There are no text books which describe how this should be done. It is the ability of the man in question to do this job, properly and thoroughly, that gives him that predominating influence of being able to choose his materials, and also the suppliers of painting materials for his shop, in a great many instances. The reason for treating the paint work in this style is really to give some idea of method, and also to show the extensive time involved to carry out the painting as described above. Given proper time it would take practically about forty-eight days, and some coachbuilders would state that this time ought to be extended to get really the finest finish, and also to give a lasting and durable wearing property to the paintwork. Customers ask "How many coats of paint do you reckon to give to Mr. ---‘s car?". And the coachbuilder unhesitatingly replies "Anything from twenty to thirty coats, sir." It is difficult to reason this out from the customer’s point of view, when he usually requires to take delivery of his car one week after the first painting operation has commenced. Today many cars change hands so quickly that it is the quick method of painting that helps to sell them. As against his forty-eight days of painting it is fair to mention what would be a fair reduction , namely, two coats of lead color with a day between each to dry. Five coats of filling up: time to dry seven days. Puttying, staining and drying: one day. Rubbing-down: one day. Ground color or common color: One day. One coat of best color and glaze and drying: one day. Leveling down and additional drying: one day. One coat of hard drying rubbing varnish and drying: one day. Flatting down, pinstriping and drying: one day. One coat of finishing varnish and then two and a half days drying. This should take approximately twenty days, or nearly four weeks of working days. One firm of large manufacturers of cars showed a method what they had adopted with quick and excellent results. The applied two coats of a special filler, which was composed of a lead compound and this eliminated the priming coats. The application of the this filler was two coats in one day. And with this filler and the addition of some dry white lead, hard putty was made for filling defects. The operation of rubbing down was done with dry sandpaper. Two coats of grey enamel and one coat of finish varnish were then applied. We must admit that as a standard proposition it certainly turned out very well. The finished car was all that could be desired, and it is doubtful if it would have been possible to have formed any idea of the number of coats, or the method used, just from the appearance of the finished article. The fenders and aprons were treated with a black enamel in a similar way. The whole operation from start to finish took five days, and no spraying machines were used. Each application made with a brush, and all the work done by hand.

Spraying Paints

With regard to spraying paints, we know of one or two large factories where this kind of equipment is employed. We find it is not entirely satisfactory. In the final operations of varnishing spray equipment is seldom adopted with any good results, and even in the earlier operations, such as spraying on priming coats, and surfacing compositions in some cases it has been found necessary to complete the operations by hand in order to make sure of satisfactory results. With regard to the filling-up operation this is very important, if good results are to be obtained at the finish. It can be readily understood that sprayed paint is nothing more or less than paint atomized, which accounts for the pithy nature of the filling when applied through a spraying machine. To enable the filling to be sprayed the consistency has to be considerably reduced, and this in itself accounts for some of the defects that are complained of, when bodies, fenders, etc,. are filled by this method. For varnishing and japanning fenders the flowing system appears to be much better. A method adopted by a firm where these two systems of spraying a flowing are in use, will given below. As will be given certain operations done by hand with brushes:

Body, With No Pinstriping or Moldings Outlined

Chassis

Cleaned off and one coat of lead color or priming, papered down.

One coat of dead black followed by one coat japan varnish, brushes throughout

Metal Splash Aprons

One coat of priming, sprayed

Three coats of surfacer, sprayed, rubbed down

One coat of japan flowed on and leveled down

One coat of varnish flowed on

The time taken to complete the painting operation by this method is nine working days. This time is improved upon in some factories by the elimination of one or two coats and requires but seven working days. Artificial heating is used to expedite the drying process. The aforesaid method is applied to the repetitious work of standard production.

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Reid