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.