Common use of Preparation and mixing Clause in Contracts

Preparation and mixing. The cement wash should be prepared as follows:- First take dry materials consisting of 75% of Portland Cement, 10% each of slaked lime and powered glue size, 3% of plaster of Paris and 2% of Alum. First place the cement in a pile and mix just sufficient water with it to bring it to a thick paste and keep it stirred with a stick. In a separate vessel mix the lime and plaster together with cement mortar to a somewhat thinner cosistency. When thoroughly mixed with, add this to the cement and stir the two mixtures very thoroughly together. In the meantime, melt the glue size with hot water and then pour this solution intu the other ingredients. Finaly dissolve the alum and add theat taking care to mix the whole well together. When this has been done, regulate the consistency of the wash by the addition of clean cold water and the best guide is to say that it would be of the thickness of fairly rich cream. At the same time, a very important point to watch is to see that no greater quantity of cement wash should be made up at one time that can be used within half an hour. If desired, this need only apply to the cement mixture as the other ingredients may be made up in bulk if required. Then if fresh quantities of cement wash are made up from time to time as they are required, the other proportion of the necessary ingredients may be added from a large quantity and thus a better uniform and more reliable wash should result.