The body generally receives a coat of priming on the bottom, top, and inside in the wood shop. This is called “slushing,” so that when the body arrives in the proof shop these parts are one coat in advance of the other portions.
The top and the panels require a considerable amount of attention. If the top is constructed of green timber it will cause the covering to rise up in ridges or blisters, and when the canvas is put on, if it is not well stretched when it is nailed on, the air gets under it and causes a deal of trouble. The inside of the top should have a good heavy coating of slush or oil lead to preserve the wood from dampness, and the outside of the top should be properly primed with clean smooth lead colour. When this is dry the nail holes should be puttied in, and sunken places brought forward with firm drying putty, which will bear blocking down with sand-paper, leaving the top as level as possible. When this is dusted off clean, apply a heavy coat of lead in oil, with sufficient varnish in it to hold the lead together.
The inside of the body should be well coated, as it is a great protection to the panels. The priming coat should be composed of the best pure keg lead and oil, with only a small quantity of drier, and allowed at least a week in which to dry. This coat should be well worked in to the nail holes and the grain of the wood. A well-worn springy brush is the best. When this coating is dry sand-paper it carefully, and apply a second coat of lead colour, using less oil. The third day after this, putty the nail holes half full; two after this, apply the third coat, mixing it so that it will dry firmly, no oil being used except that which is present in the lead. When dry, finish puttying the nail holes; also putty up any of the grain that may appear too open, or else rub into the grain some lead mixed up very heavy.
The body, after having received three coats of lead, and been puttied up, may now stand for two or three days. When it is again taken in hand, sand-paper off any putty that may be above the level of the surface; dust off, and brush on a level coat of lead, which must dry hard and firm. Every coat of lead should be laid on as level as possible, and made to fill up the grain of the wood as much as possible. These coats are called “rough stuff.” The body may now stand for three or four days, when it will be ready for the filling up.
There are two very important things to be studied in coach-painting. First, to form a surface hard enough to hold out the varnish and disguise the grain of the wood; and second, to have the first and intermediate coats of paint sufficiently elastic to adhere and yield to the natural action of the wood without cracking or flaking off. In effecting one of these results we are apt to affect the other; and nothing but the utmost care, on the part both of the manufacturer of the essential ingredients and of the person who prepares them for use, can insure durability.
The leather-covered portions are usually primed with two coats of black Japan, reduced with a little turpentine.
A good stopping material for nail holes, &c., is made of dry lead and Japan gold size. It is called “hard stopper.”
The rough coatings should dry firmly, possessing only sufficient elasticity to bind them to the surface. The first coat will bear a trifle more oil than the remaining ones, and should stand about four days before the others are put on, which can be done every other day.
Five coats of filling up are next added, composed as follows:—
2 parts filling up stuff.
1 part tub lead.
2 parts turpentine.
1 part Japan gold size.
½ „ bottoms of wearing varnish.