Lime mortar for masonry - how to make it right?
In the lime mortar is slaked lime and sand. In order for the masonry to be strong, you need to know how to prepare the solution, and what you need for this. To prepare it requires compliance with a number of conditions, one and which, this is the correct damping. It is carried out in a special container, where water is added in small portions.
But even from the times of grandfather, the best place to store lime was considered to be an earthen pit covered with wooden boards, which was sprinkled with a half-meter layer of soil. In this form for several years, she gradually gained the necessary properties. It is not difficult to master the preparation of a lime mortar. Start work with straining through a sieve of milk of lime, where fine, sifted sand is added.
The mixture is thoroughly mixed and water is added in small portions. The density of the solution depends on its quantity. For completeness instructions how to make a mortar, it remains only to say that for one part slaked lime experts recommend adding no more than 2-3 parts of sand. In order to increase the strength of the batch, it involves a small portion of cement or gypsum.
Lime plaster mortar - what is special about?
Next we will stop on the solution, which is used for plastering works. Plaster is the most common way of finishing walls and ceilings. Depending on the quality of the execution is divided into simple and high-quality plaster, which differ in the size of the tolerance of irregularities.
The plaster coating process consists of three stages. The first layer - spray, the second - the soil, and the third - cover. Their total thickness usually does not exceed 25 mm. If a larger layer is required to level the surface, then a special plaster grid is used as the reinforcing coating. A lime plaster solution is prepared by mixing a slaked base and fillers such as sand, slag and other available materials.
There are plaster solutions, greasy and lean. In fatty mixtures, a significant percentage of the binder is present, resulting in severe shrinkage and cracking. In lean solutions on the contrary - there is a lack of lime, gypsum or cement. They do not shrink, they do not crack, but they are less ductile and less durable.
Aspect ratio of lime mortar for plastering
A plaster mix is prepared in accordance with the proportion of the lime mortar. To reduce the time of setting, gypsum is added to it. The components are thoroughly mixed and then used for five minutes, as the plaster quickly solidifies. For the plaster mixture, which is prepared for the first layer( spray), one part of the lime solution is added with a part of the gypsum and three parts of the water. For soil, this ratio is 1: 1.5: 2.The covering is prepared from a part of the calcareous mixture and one and a half pieces of gypsum.
The final hardening of the plaster comes in 30 minutes. To somewhat slow down this process, bone or glue is added to the plaster solution.
The density of the lime mortar depends on the quality of the filler. Mixtures of medium density( 1500 kg / m3) are prepared using river sand. On the basis of porous fillers( pumice and tuff) solutions with lower specific gravity and low density are obtained. In order for the plaster to lie well, the walls and ceilings must be pre-prepared, cleaned of various contaminants and moistened with water.