In the case of many old walls, large cracks or breaks in the plaster have to be cared for. It is wise to remove or cut out any loose plaster with the edge of the broad knife. With the brush and warm water, wet thoroughly the new edges from which the loose plaster has been removed. Take a quantity of Plaster of Paris, put it into the center of a good sized board; build it up into a cone with the thumb and fingers; make a hole in the center of this pile; using the handle of the broad knife, pour in a little water allowing it to soak into the plaster. Use the wet plaster from the center of this pile and pack it into the cracks and holes. Smooth this patch even with the wall, before the plaster hardens. Use the broad knife for this work.....By pouring the water into the center of the cone and using just the amount of plaster that is wet, we prevent the too rapid hardening of all the plaster. Should any of the plaster drop on the woodwork or fixtures, wipe it off immediately, using a sponge and clean water. Be sure that the Plaster of Paris patch is packed in closely and built up until the edges are even and the new work level with the old plaster wall. Should the plaster dry before it has been smoothed sufficiently, wet the patch with the calcimine brush and smooth with the broad knife.
Fig. 62. - With information on methods of preparing walls for new finishes and methods of refinishing, satisfactory results may be obtained. The illustration is a Better Homes project.
Where soda water was used (as in the case of varnished wallpaper) the wall must be sponged off with vinegar water. Be sure to use cider vinegar. This is a treatment that should be given to new plaster where it is desired to use paint or wallpaper very soon after plastering.
\ lb. painter's glue, cold water, 4 quarts boiling water, No. 2 sandpaper, brush.
After all paper or cold-water paint has been removed and all cracks and holes have been filled, the new plaster in the holes and cracks must be allowed time to dry thoroughly. Soak the painter's glue until it is soft, in enough cold water to cover it. Pour off the surplus water. Now pour on the glue 4 quarts of boiling water (be sure it is boiling). Sandpaper the wall using No. 2 sandpaper. Use the calcimine brush and apply the glue water (size) to the wall. Brush it in thoroughly and evenly. Wipe any glue-size off the woodwork before it dries, using a damp cloth or sponge. When the glue has dried thoroughly, the wall is ready for either oil paint or wallpaper as a finish.
For the best result, allow the newly plastered wall to dry at least six months. Wash the plastered wall with strong vinegar water if the wall is to be painted before that time. Cover up small fine cracks and any porous spots by giving the walls a coat of glue-size, when it has dried. Brush the size on the cracks by using a sponge, thus preventing the size from settling in the cracks and showing as a dirty looking streak.
No. 2 sandpaper, i lb. washing soda, stirring stick, 4 quarts of warm water, brush, old cloths or newspapers, glue water, 1 quart molasses.
Mix the soda in the water (1/4 lb. to 4 qts. warm water). Be very careful to protect the woodwork and floor. Use No. 2 sandpaper over the whole wall surface. Go over the entire wall with the soda water, using the calcimine brush. The sandpaper and soda water break the hard, smooth surface of the paint which would be impervious to the paste which must be used to hold the wallpaper to the wall. Wash with vinegar water. When the wall has dried after the vinegar wash which followed the soda wash, go over the entire wall with the glue-size. In order to insure a good coating on the wall, add one quart of molasses or two pounds of brown sugar to the glue-size when making it for a wall that is to have wallpaper put on. Brush the glue-size on thoroughly and evenly.
Test before papering. Take a small piece of wallpaper and the paste to be used and press it to the sized wall leaving the corners free. After a few minutes remove it. If it pulls off easily and without tearing, the size is too thin and should have more glue added. If the paper sticks tight, the glue is of proper consistency.
Walls must be perfectly smooth and dry. Give a coat of hot glue-size. Allow to dry thoroughly. If this coat does not show on the surface of the wall, give a second coat of glue-size. Oilcloth covering does not need a plaster wall for its use. It can be tacked directly onto wooden walls. It comes forty-eight inches wide and thirty-six feet in length, when made especially for use as a wall finish.