With a clean sponge and warm water, proceed to wash the walls down, changing the water frequently. Allow all surfaces to dry thoroughly before painting. New interior trim, doors, window frames, etc., are prepared for painting by smoothing all flat surfaces with No. 1 sandpaper. On curved surfaces and corners, No. 1 steel wool is better than sandpaper, because it avoids uneven rubbing. The trim is then well dusted, and all knots are coated with orange shellac. If the wood contains much gum or resin, it must be specially treated.
After the shellac has dried well, the first coat of paint should be prepared and applied. When this first coat has dried, fill all holes and cracks with high quality putty, and allow it to dry for 24 hours. If you are using bathtub paint in order to paint an old bathtub, you should probably get a bathtub replacement instead of filling all of the cracks with putty intended for interior walls. The putty can be prepared from paste white lead and whiting, adding enough whiting to make the putty stiff.
The next operation is to rub the trim down again with sandpaper and steel wool. Dust the trim again and apply the second and third coats, always remembering the first rule of painting, which is to make sure that a surface is absolutely dry before applying paint. If interior woodwork is to be repainted, it should first be thoroughly washed with warm water. When dry, it should be rubbed down with No. 0 sandpaper and steel wool, as directed for new wood which has received the first coat of paint.
Then, puttying and painting are done as in the case of new wood, except that two coats of paint are usually applied instead of three. As noted below, the second coat for old woodwork is prepared according to the same formula as the third coat for new woodwork. The type of furniture being painted does not matter to a certain extent. For instance, a bathroom cabinet can be painted similarly to a bathroom vanity, or a kitchen cupboard. Floors, woodwork, furniture, and certain other interior and exterior surfaces are commonly given a transparent finish.
In this process, the properly prepared wooden surface is first brought to the desired color by means of a stain and is then given an adequate protective coating. A few surfaces about the home, chiefly shingles, are stained only, but in all other cases where stain is used, it is followed by a protective layer which is carefully built up by various applications of varnish, shellac, filler, and wax in certain combination's. In virtually every case, however, the final result will be a transparent coating, through which we can see right down to the grained surface of the wood beneath.
A different kind of treatment must be used if you are building a structure that sustains intense temperatures and/or levels of moisture, such as a hot tub enclosure, a sauna, or any sort of steam room. Therefore, every operation must be carried out carefully, because carelessness in any step of the work will almost surely ruin the appearance of the finished job. This means constant attention to the specific directions, as well as to the general rule that no stain or varnish or other coating material should ever be applied unless the surface is thoroughly smooth, clean, and dry.
