The advantages of applying paint, japan, enamel, or varnish by the process of immersion are obvious. The saving of time is the chief advantage, and this will be in most cases very considerable. For instance, a complete wagon can be painted by dipping in a very few minutes, while large and intricate agricultural machines may be painted in the same way in a fifth part of the time it would take to spray them, and probably a twentieth part of the time it would take to do the work by hand.
There is another advantage which should be mentioned when paint dipping is compared with spraying. In the latter, an outfit consisting of sprayer, air compressor, exhaust, cabinet, etc., are all necessary. In dipping, however, the apparatus may in many cases be of the simplest character. For example, in painting bedsteads all that is necessary is a narrow but deep tank containing the paint, into which the bedstead may be plunged by hand and then hung up to drip over a metal-lined floor.
[Illustration: Fig. 16.--A MORRIS STANDARD ELECTRIC TROLLEY HOIST.]
In Birmingham, hundreds of iron bedsteads are dipped in this way every day. The head or foot of the bedstead is taken in the two hands of the operator, dipped into a tank of black japan, and immediately hung up on a travelling chair, which slowly carries it across the room to the oven, the superfluous paint dripping off during the process.
In another chapter will be found the advantages which the process of spraying has over dipping. A decision as to which is the best system to adopt for any particular purpose can only be determined after due consideration has been given to all the circumstances bearing upon the work to be done.
It may be pointed out in this connection that the process of painting called "flowing on," which is fully described on another page, is in effect only a modification of dipping. As a motor body, for instance, cannot be plunged into a paint tank because the inside is not to be painted, the paint is literally poured over the surface, and the effect is exactly the same.
It frequently happens in paint dipping that certain parts of a machine or other article that is desired to be coated with paint is to be left unpainted, and the problem is how to effect this most economically. The method usually employed is to cover the parts, such as name plates, bright portions of a machine, etc. with vaseline. When the article is dipped the paint covers this as well as the other parts, and after the paint is dry the vaseline and the paint on it can be easily wiped off and the surface beneath it will be found to be quite clean.