Polycell Rockset to fix up chips
There's nothing more frustrating than finishing off a plastered wall with perfect edges and then some twit comes along and knocks a big chunk out. I have previously used Polycell Rockset for filling in dings and bumps on corners in the house, and it came in handy again today for fixing up damage to exterior walls.
Crackfiller is ideal for filling in small cracks, but it doesn't work when you have large cracks and missing chunks in a plastered wall. Polycell Rockset, like crackfiller, comes in a fine powder that is mixed with water to a thick paste. Once cured, the finished repairs have greater compression strength than conventional concrete, which means it is ideal for chipped plaster. You will find Polycell Rockset at your local Builders Warehouse.
When using Polycell Rockset you need to brush the area to remove any loose particles or dust. It also helps to lightly dampen the area before application, and you can use a paintbrush for this as well. In an old paint container or plastic tub add water to Polycell Rockset to make a thick paste. To do this, only add small amounts of water at a time until the paste can be stirred easily but is not runny. Use a putty knife or paint scraper to apply the product to the damaged area. If you are building up a chipped corner, only mix enough Rockset to apply one layer at a time, allowing a 10 minute interval between layers. Rockset starts to set very quickly and if you make too much you will have to dispose of it. As you apply each layer you need to shape it to the area to be filled, in my case a missing chunk in the corner of the wall. Use a putty knife of paint scraper to smooth to shape. Allow to dry overnight and then sand away any roughness with 60-grit sandpaper.
When using Polycell Rockset to fill in cracks, use a small chisel to chase out and enlarge the cracks to a deep 'V' shape before applying Rockset. This will ensure that the filler goes down to the base of the crack and provide more strength and reduce the risk of the crack occuring again later on.
Since the repairs were done on an unfinished plaster wall I still need to apply plaster primer before painting, but when used on exterior surfaces Rockset should be protected with a good quality exterior paint, such as Plascon Micatex or Wall & All.