PATCHING INSTRUCTIONS
Preparation
Cut away all loose deteriorated stone in a damaged area until stone is reached. Cutting out is best done with a hammer (hand or air) and a tooth chisel.
Leave a rough or chiseled surface for best possible adhesion of patching material. Areas cut out for patching should not have feathered edges but should be cut straight in along this outer edge (see figure A).
FIGURE A
Before application, thoroughly brush off dust and debris, then wash surface with brush and water. The surface to be patched must be damp (not over-saturated) with water to ensure proper bonding when material is applied.
Mixing and Application
Just before mixing patch material you can apply the white liquid (Acryl 60), which is a bonding agent, with a small brush, being careful to only put it where the patch will cover it since it turns the stone white.
Mix 2 parts sand with 1 part cement. Add water and mix thoroughly to about the consistency of cookie dough.
The patch is best applied from a hawk with a margin trowel or plaster tool. Press material directly onto the damp stone. Build patch higher than surrounding stone, so that by removing the excess with a very sharp trowel or knife brings the patch level with the surface of the stone. Before the excess is removed, the stone should “take up” the moisture from the patch, causing its consistency to somewhat harden. When the excess material is removed, and moisture appears behind the knife, the patch is still too wet. If the surface of the patch appears to be rough, after striking, smooth with trowel. Then lightly dab the patch with a soft damp sponge to achieve proper texture, and clean area around the patch with a soft sponge so there is no residue left on the stone.
The color of the patch material has been matched to the color and texture of a caststone sample after it has been lightly washed with Sure-Klean 6000. For the closest possible match, it is recommended that the patching be done after the stone has been cleaned. If necessary clean any smears off the stone adjacent to the patch with a damp sponge.
If the following curing procedures are not followed the patch will turn to powder crumble when touched and be washed out when the building is cleaned.
When the patch has been on for about two hours, a light misting of water should be applied; sooner if it is hot or in the glaring sun. It is important to do this at least twice the first day the patch is on; more often if it is hot. Take care not to water too much. If the patch is misted too soon, it will melt like a sugar cube. After a patch has been on for approximately six hours, it can be covered with plastic and taped. This will properly cure most patches without any additional wetting. After patch has cured 24 to 48 hours, wash patch and surrounding area with a solution of 20% Sure-Klean 6000 and 80% water. Rinse thoroughly with clean water.
Color Matching
The patch kit contains patching material matched to the correct color of the caststone after the stone has been washed. The best procedure is to make a couple of small patches in an unexposed area. Cure them promptly, and allow them to dry to determine if the patch matches.
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catescaststone@suddenlinkmail.com