The application of microcement, as a technical material that it is, is a process that must be perfectly controlled. All steps are important in order to achieve a perfect finish. Sanding the microcement is often an underestimated step and if it is not correct, a good result will not be achieved.
In this article we will talk about sanding, and how it can affect the final result. The first advice we can give from Lunik is that the sandpaper must be of good quality. The reasons are two:
Once we are clear about how the sandpaper should be, we must choose the grain size. At Lunik we recommend using 40 sandpaper for the bases, and 120 sandpaper for the microcement finish layers. The first layer of polyurethane can also be sanded, although in this case we recommend using 400 grit sandpaper.
In any case, the layer must always be completely dry before sanding. This is very important, since if it is not fulfilled, the layer could be damaged.
Then the sanding process will begin with the first coat of tile grouting, if any, or the first coat of base. It is important to note that due to the minimum thickness of the microcement, any marks that exist in the first layers will carry over to the last. That is why we must ensure in each layer that the result is what we are looking for. Another consideration is that to avoid spending too much time sanding, we must work the material well with the trowel.
Once the first coat is completely dry, we will go on to the second base coat, and we will continue with sandpaper 40. Later we will apply the two layers of fine, waiting for them to dry before sanding each one of them. If in the base layer it was important to work the material well with the trowel, with the fine this is necessary because with the sandpaper it will be difficult to correct a very irregular surface.
Later, with the first layer of polyurethane, we can use sandpaper 400 to finish polishing the surface and leave it completely soft to the touch.
Ask us about the best sandpaper for any microcement job. Visit us on our Lunik website to see all our products.