As part of surface preparation, when repainting plastered surfaces, cracks are often an issue. Hairline cracks can be sanded to a smooth profile, spot primed with Plaster Primer then over-coated with two coats Elastocryl prior to recoating the wall. The two coats Elastocryl will give 210 microns of film thickness, before the top coats are applied. The total film thickness over the crack will then be sufficient that should the crack re-open due to movement of the substrate, the paint film above it will not break.
Larger cracks should be raked or angle ground open, to a sound substrate, before re-filling. Here we recommend the use of Weathercrete - pre-weighed cement to be mixed with the polymer supplied, to be used as the fill compound. The resulting profile of the dry fill will match the surrounding plasterwork to a far greater degree than when using cellulosic fillers. Patting the surface of the still wet filled area with a damp sponge helps to match the surrounding plaster profile. Once this is dry, spot prime the repair with Plaster Primer, over-coat the repair with two coats Elastocryl and proceed with the application of top-coats.
Weathercrete can be used to fill plaster defects on cement floors, as a waterproof grout between tiles, or even as a tile adhesive. Be sure to clean the equipment used with water directly after use, as once dry, the adhesion to metal is so good that you may have to angle-grind it off.
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