At some point in the life of the home, cracks or holes will have to be filled with plaster on some of the walls of the house, due to its own deterioration, or as part of the normal plastering preparations. In this sense, there are the tasks of eliminating a chimney or treating an entire wall or even eliminating one of the walls of the house.
A bricked-up fireplace constitutes a space large enough for the hobbyist to get a good practice in the handling and use of masonry tools, without involving an excessively complicated job. These types of repairs can be done with single coat plaster or with a primer and a finish coat.
When a piece of a plastered corner has been broken and brick is visible, it can be perfectly rebuilt by plaster with one or two layers. To do this, use a 100 mm wide strip to do the job well and accurately. Using the chisel, remove the plaster from the damaged edge of the corner and expose about 100 mm of the brick wall. If using two-layer plaster, first position the guide board against the old plaster. Then nail the wall, but away from the corner so that it is not damaged more than it is.
Mix the plaster of the primer coat, wet the brick wall and the edges of the old plaster and fill in the side that is level with the board, but not the wall. Then scrape off the new plaster with the trowel. When the plaster is hardened, remove the board from the wall to prevent the new plaster from coming off. The new edge that has been worked on represents one of the faces of the finished surface, so you will need to refine it with the trowel and ruler.
Once you have finished and let the plaster dry on one side, nail the board again on the other side without fixing, but this time up to the level of the new corner. Do the same procedure as before and fill the gap that appears with plaster. If necessary, moisten the primer coat to improve the adhesion of the plaster. When both sides are firm, buff the new plaster with the trowel, rounding the right angle. Afterwards, let the whole set dry, so that later it can be painted again as the color it had previously.
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