Preparing plastering
In this article we will show you how to prepare a plaster mortar using all known materials, ie sand, cement, clay and lime.
Important! Any mixture includes in its composition aggregates, binders and liquid.
The most popular astringents used in solutions are clay, cement and lime. As a filler, sand is usually used, and liquid is ordinary water. Typically, the composition of the finished material includes one binder and one aggregate, but sometimes, two binders are used. This is possible when adding cement to the lime-sand mix.
Depending on the proportion of the plaster mortar, it is divided into three types:
- bold: contains an excess of binder. After such a compound dries, it cracks;
- normal: the correct ratio of filler and binder.
- skinny: contains an overabundance of filler. Such a solution is fragile, brittle, and short-lived.
How to understand if the plaster is properly diluted?
To understand what kind of solution( lean, greasy or normal), it is necessary to lower the trowel into it and see:
- solution adheres to the trowel with pieces - it means that the composition is fat;
- trowel slightly dirty - then the plaster is thin;
- the composition sticks to the trowel not much, creating a thin crust - hence, normal.
The plaster solution usually includes sand and cement, that is the most popular plaster, prepared in-house, is cement-sand. The mark of cement affects the ratio of sand. When using M-400 cement, the recommended ratio should be 1: 3, that is, 1 part of cement to 3 parts of sand.
The composition must first be mixed dry, then gradually adding water, stir until the solution has acquired the necessary consistency. When the mixture is ready, you can add to it the construction adhesive PVA, in the proportion of 50-70 grams of glue for 10 liters of plaster.
Lime and clay mortars
Lime based plasters are prepared using sand and lime paste. The ratio of sand to paste depends on the fat content of the lime. In this case, not everyone can figure out how to make the plaster solution "normal".But there is one rule that can help: in the preparation of such a composition, it is necessary to control its fat content, gradually adding sand to it.
If you add 1 kilogram of cement to 10 kilograms of lime mortar, its strength will increase several times. Plaster based on clay is prepared using the same technology as lime. The proportions in this composition also depend on the fat content of the solution. In such a plaster, you can also add cement.
Important! If plaster is needed to perform outdoor works, then it is best to make an ordinary cement-sand composition.
Preparation of plaster, its composition and proportions depend on the surface to be applied to. Each type of plaster has its own characteristics and scope. Some can be used for both indoor and outdoor work, and some, for example, only indoors.
Not every solution can be used to cover any surfaces, which is why the correct choice depends on how long the plaster will last.
