THE PLASTERER AND WHITEWASHER.
WHITEWASHER AND PLASTERER.
When the walls, or what is called the carcase of the house, have been built, the roof made, the inner walls and partitions set up, and the joists and woodwork of the floors laid down, the work of the Plasterer begins. He covers the brickwork and bare timbers of walls, ceilings, and partitions with plaster, to prepare them for painting or papering: he also forms the cornices for ceilings, and the mouldings and decorations, which are usually made in plaster or cement.
The materials which the Plasterer uses for these purposes are:—1st. Coarse stuff, or a paste made with lime, much in the same way as common mortar, and afterwards mixed with hair, which is obtained from the tanner’s yard, after it has been removed from the skins, which are there made into leather. This hair is raked together, and mixed with the mortar, with the hair hook, and a sort of three pronged rake called the drag.
Hair Hook. Fine Sieve.
2d. Fine stuff is made from pure lime, slaked with a small quantity of water, after which enough water is added to bring it to a state in which it resembles cream; it is then left to settle, the superfluous water is poured off, and the mixture is left in a tub, till still more of the water has evaporated, and it is thick enough to use. This stuff is often used for ceilings, and then a small quantity of white hair is mixed with it, to help to make it firmer and more binding. For these finer kinds of plaster it is necessary to use the fine sieve, in order to sift the lime and other ingredients, that only the portion which has been reduced to powder may be retained.
3d. Stucco, which is made by mixing fine stuff with cleaned-washed sand. Stucco is used for house fronts, or other finishing work, which is intended to be painted.
4th. Gauged stuff is used for forming cornices, which run round a ceiling, and for mouldings; it is made by mixing fine stuff with plaster of Paris, which is a fine white powder easily made into a paste, and drying very quickly.
These are only the ordinary materials used by the Plasterer for his work, but there are a great number of cements, which are also applied in the course of his trade; such as Roman and Portland cements, and mixtures made and sold for special purposes of decoration, and the manufacture of ornaments.
These ornaments, such as centre pieces for ceilings, flowers drooping from cornices, bosses or groups on walls, &c. are first modelled in clay, and are afterwards cast in plaster of Paris, placed in moulds made of wax or plaster. In this trade, as in that of the picture frame maker, ornaments are frequently made of papier maché, or the pulp of paper (literally smashed paper), which is a very light, hard, and durable substance for the purpose. The moulds for cornices are made of sheet copper, and are fixed in a wooden frame.
Gauging Trowel. Hammer. Salve. Plasterer’s Hawk. Check Line and Reel.
The various tools used by the Plasterer are shown in the engravings, and the manner in which some of them are used may be seen by the large cut at the commencement of this description of the Plasterer’s trade. The peculiar hammer, with one edge like an axe, is used for breaking down old plaster, and clearing away the mortar from walls and ceilings previous to plastering them afresh; the hawk is a flat board with a handle in the centre, used for holding the plaster or cement, which is being laid on with the trowel. The gauging trowel is the long narrow trowel, used for taking up the fine stuff for cornices and mouldings; these trowels are of various lengths, from three to seven inches. The salve is a sort of small spade, on which the plasterer’s boy lifts the mortar or cement, and places it on the hawk, which the workman holds in his hand; as the salve has a long handle, the plaster can be conveyed to the hawk even when the man is at work on a ladder. The square is similar to that used by the bricklayer, and shows that the corners of the work are straight and even; the compasses are used for measuring distances; the check line for marking out the spaces of the work to be done, and the joint rules for measuring the parts where different portions of the work come together, either at the corners, or in making the mouldings. The set square is also used, for showing that the surface or the line of the work is straight and even.
Joint Rule. Joint Rule. Compasses. Set Square.
When the Plasterer has to cover a ceiling or a partition, he commences by lathing. This is nailing laths over the whole space which is to receive the plaster. Laths are long narrow strips of either oak or fir wood, of various thicknesses; the thicker being used for ceilings, where they have to bear a greater strain than in upright walls.
The next operation is pricking up, or placing the first coat of coarse stuff upon the laths; this is called pricking up, because when the plaster is laid, its whole surface is pricked and scratched with the end of a lath, that it may be rough enough for the next coat. The laying on of this second coat of plaster is called floating, and is performed in the following way. The surface is surrounded with narrow strips of plastering, called screeds, held fast by lines of nails, and these are made perfectly level, by means of the plumb rule ([see Builder’s tools]), and the use of the hand float. The spaces within these lines of plaster work are then filled with coarse stuff, till the whole forms a flat surface, which is made perfectly level, or “floated” with the floating rule. Other screeds are then formed and filled up in the same way, until the whole ceiling, or wall, forms one flat surface. The operations are the same for ceilings and walls, except that the plumb rule is used for adjusting the level of walls, and the level for that of ceilings.
Square. Modelling Tools. Brush. Floating Rule.
After the work has been brought to an even surface with the floating rule, the Plasterer goes over it again with the hand float, using a little soft stuff to make good any deficiencies.
Hand Float.
When the floating is about half dry, the setting or finishing coat of fine stuff is laid on, and is first wetted with a brush, and then worked over with a smoothing tool until a fine surface is obtained.
Stucco is laid on with the largest trowel, and worked over with the hand float—being at the same time sprinkled with water—until it becomes hard and solid; after which it is rubbed over with a dry brush. The water has the effect of hardening the face of the stucco; which, after several sprinklings and trowellings, becomes very hard, and as smooth as glass.
Setting Trowels.
The commonest kind of Plasterer’s work is laying on one coat of stuff: when this is done on brickwork it is called rendering, and when on laths it is called laying. When there is a second coat it is called render set, or lath-lay and set: and when it is three-coat work it is called render, float, and set, or, lath-lay, float, and set; this is done in ceilings and partitions with fine stuff mixed with hair; or, when the walls are to be papered, with fine stuff and sand.
Rough stucco is used for finishing staircases and passages in imitation of stone. It is mixed with a great deal of coarse sand, and is not smoothed, the hand float being covered with a piece of felt, so that when it is applied to the stucco the grit of the sand sticks to it and is drawn to the surface, giving the plaster the appearance of rough stone.
Rough casting is used for outside walls, and is done by throwing a layer of gravel, mixed with lime and water, over the second coat of plaster while it is quite wet. In some counties of England, and especially near Nottingham, the plasterers use reeds instead of laths; and even floors are often made by laying down a quantity of coarse stuff upon a foundation of reeds.
These floors are almost as hard as stone, and possess the good quality of being almost always fireproof.
