Within the past three years corner beads made of rolled steel have been patented and placed on the market. The advantages sought in these metal corner beads are to obtain a smaller bead, thereby making a more sightly corner and to hold the plaster so that it cannot crack or crumble away at the angle. They can also be made perfectly straight and can be papered over better than the wooden bead.
To the present time four different patterns have been patented, the Union, the Marsh, the Parker and the Empire, all aiming to obtain the same result.
The superiority of one pattern over the others will probably be determined by its adaptation to practical use or the facility with which it can be applied.
At the present time but two of these corner beads, the Union and the Empire, are on the market; the Parker having been absorbed by the owners of the Empire, while the Marsh has been practically withdrawn.
The Union Metal Corner Bead, shown in Figs. 194-196, A, has been used quite extensively during the past two years in New England, New York and Philadelphia, and appears to be a meritorious and practical device, especially when applied to wood furring or studding. It is made of No. 24 rolled steel, perforated and cut into strips and bent on a die to the shape shown in Fig. 195 and then galvanized, the zinc coating soldering the sides together where they touch. This bead is made in sizes for 3/8,5/8 $ and ¾-inch grounds and in lengths of 6, 7, 8, 9 and 10 feet; it can be obtained bent to any radius for arches. It is shipped in bundles containing from 60 to 100 feet and weighing from 7 to 20 pounds, according to size and length. The cost of the bead varies from 4 to 5 cents per foot, according to locality.
On woodwork it is secured by nailing through the small holes in the flanges, and can be put up as rapidly as a wooden bead.
On some kinds of brick or tile work it may be secured in the same way, but owing to the nails coming so near the angle they are apt to break the brick or to push out the mortar, so that on brickwork and dense tiling better results are usually obtained by securing the bead by means of short pieces of wire hooked to the bead and bent around the head of a nail, driven at a convenient place in the brick or tile work. By using two pieces of wire and twisting the ends together, as shown in Fig. 196, any degree of tightness may be obtained.
Fig. 195 - Union Metal Corner Bead.
Fig. .196.-Union Metal Corner Bead.
The wires for this purpose are furnished with the bead, and the makers claim that a mechanic with helper will put up 300 feet per day in this way and get a straight line.
For irregular brickwork the makers advise that the ¾-inch bead be used. When 7/8-inch grounds are used on woodwork the bead may be nailed over laths, as shown in Fig. 195.
This bead appears to have an advantage over those with the edge formed of a single thickness of metal, in that a folded edge is mole easily made and kept straight than a raw edge.
The Parker Corner Bead was made of a single strip of steel, 1 ¼ inches wide, perforated to allow the mortar to pass through it, and bent laterally to an angle of 45 degrees. The metal strip was then fastened to strips of wood to facilitate putting it up. This bead, however, has been superseded by the Empire.
The Empire Steel Corner-Plate, shown in Fig. 198, is especially designed for use on brick and tile corners, although it can be applied equally as well on wood.
The plate is made of No. 16 Bessemer steel (being the scrap from bicycle chain links), not galvanized, and in lengths of from 8 to 12 feet, which are not only perfectly straight, but cannot easily be bent.
The plate is attached to the walls by means of angle irons, which have a key punched out on the side that can readily be en- ' gaged in the plate and which at the same time holds it firmly in place. These angles are keyed to the plate before it is put up, at such distances as may be necessary - about 20 inches on an average - and are then nailed to the wall or studding.
The nail holes in the angles are at a sufficient distance from the corner as not to break the bricks or tile, and to get a good hold ; moreover, the nails being driven on both sides of the corner, the angle cannot possibly be detached without drawing the nails. The plate should be put up by commencing at the top and working downward, blocking the angles where necessary to keep the alignment.
On woodwork the perforated plate is nailed directly to the wood without using the angle irons.
Fig. 198. - Empire Corner Plate, Half Full Size.
The manufacturers of this corner bead have also devised a method of ornamenting the edge of the plate by cast brass beadings or ornamental strips in almost any design that may be desired. The cost of this corner plate, including the angle irons, is 6 cents per foot in Philadelphia and adjacent cities, where it is meeting with much favor.
The Marsh Metallic Corner Bead consists of a 5/16-inch galvanized steel rod, grooved to hold the plaster, which is held at the desired distance from the rough corner by means of metal clips which are made in forms suitable for applying to brick, wood or steel. This bead gives a rounded corner of about 3/16 inch radius. The author understands that it is not now on the market.
When specifying metal corner beads, more satisfactory results will probably be obtained, especially in the smaller towns and cities, if they are included in the carpenter's specifications, as it is important that they be set true and perfectly plumb, and a carpenter is, as a rule, more skillful at such work than other mechanics.
Either a wooden or metal corner bead affords a considerable saving in time to the plasterer, as the bead forms a guide for the trowel, and the plaster has only to be brought to it. To form an "aris" corner in plaster, square and plumb, costs from 4 to 6 cents per foot, so that when a corner bead, and especially a metal bead, is put up by the carpenter, the plasterer should make an allowance on account of it in making up his estimate.