In order for the repair to serve for many years, it is necessary to take care of the correctness of the implementation of all its stages. Far from the most important stage is the processing of surfaces before painting (in particular, their cleaning from the old paint). To date, the main ones are three cleaning methods: mechanical, thermal and chemical. The mechanical method implies the use of a spatula, a jack of a hammer or a chisel, a hard brush or a grinding machine. This simple method has a significant drawback: the tools can not only remove the paint layer, but also damage the painted surface, which will require the further use of the putty. In addition, when using a grinding machine or brush, small ash can form, which can damage the respiratory organs and vision. You may also be of interest to the allowance of designers. The thermal method involves the use of heating devices (for example, a building hairdryer) until the varnish or paint softens, will acquire plasticity and will begin to easily remove. But not all varnishes and paints can be removed in this way, in addition, there is a great risk of damage to surrounding objects from the heat. It must also be remembered that stone and metal surfaces absorb heat, preventing the paint from gnawing to the optimum temperature: on such surfaces, the method is ineffective. The chemical method requires aggressive washing for softening, dissolving and removing paint. It is necessary to remember about personal protective equipment, as well as the ventilation of the room. When choosing a method, it is necessary to take into account its safety in a particular situation, the material of the purified surface, convenience, efficiency and cost of the method.