Plaster prepare from knitting materials and fillers. Clay, building plaster (alabaster) concern knitting materials cement, izvest. For preparation of plaster solutions all are suitable listed knitting, but stronger of them is cement. It provides to building and plaster solutions high durability and moisture resistance. .
Cement represents a powder of grey colour which at mixing with water hardens and is turned to stone. Shvatyvanie it begins in 30-60 minutes after connection with water and comes to an end approximately in 12 hours. The further hardening proceeds till 28 days.
Izvest serves as the basic knitting material. It receive by stone-limestone roasting in which result porous pieces of yellowish colour are formed. Such kind to exhaust is called as not slaked. Use not slaked or poorly slaked to exhaust worsens quality of plaster. The earlier before the use it to put out, the it will be more qualitative. The earliest term of use after clearing - 2 weeks.
Extinguish izvest water in a box or a flank. At connection not slaked to exhaust with water it is allocated warmly. After cooling its pieces break up and turn in white kashitsu which name pushonkoj. Slaked izvest it is possible to store in a hole dug in the earth and sheathed by boards. .
From pushonki receive the limy dough by addition in it waters. After razbavlenija water it turns to limy milk. .
Clay - a natural material. As knitting substance it apply in the simple and mixed clay solutions. For preparation of the clay test a material soak water, maintain some days at periodic humidifying. However clay is not enough water rack also is strong.
Fillers concern sand, slag, charcoal, pumice, gravel, etc. Sand is heavy (or cold) a filler, and slag, charcoal, pumice, etc. - easy (or warm). .
Sand happens with large, average and fine grains. For plaster solutions usually use medium-grained sand, and for nakryvochnyh - fine-grained.
Slag sand apply to manufacturing of thick plaster coats for the purpose of warming of premises. It receive from slag by means of crushing and sifting.
Charcoal use for preparation of warm solutions instead of usual sand. For this purpose it split up and sift. .
Pumice as a warm filler is added in a solution in the kind crushed and sifted through a sieve.