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Home > we have manipulated as accurately...
Previous Next The best candle and soap tips online! we have manipulated as accurately as possible, it. will only be an equalizing of a small overplus of fat or lye, and we must not always be too ready with ammunition of large calibre, and add large quantities of lye and fat all at once. This it is that leads to confusion, out of which it is difficult to correctly find our way again, and by which the soap instead of improving is made worse. All manipulations which are undertaken with extempore soaps amount finally to this, to produce the most neutral soap, and to fix the proper proportion between fat and alkali; since an overplus, be it of the one or of the other, works equally injurious. The soap is boiled in two waters and the fat substance is in the first place saponified, with a 13° or 14° B. soda-lye, then the rosin is added, and the boiling continued until a eoap mass becomes visible; when the heat is turned oft', and on the following day the sub-lye is drawn out. In the second operation it is boiled with a 10° B. lye, but, if it should show a smeary or weak condition, it can be remedied with a lye of 12° B. The boiling is now continued until no defect is visible, and after a rest of three hours, the soap is run into the frames. Another modification of this process is, when the sebacic acids or fats are saponified with the requisite quantity of caustic soda, of about 20° B., in a moderate heat of about 49° C. (120.2° F.), the ingredients being slowly combined with constant stirring, the heat gently raised to a boil, and sufficient water added at times to keep up the due proportion of loss by evaporation. The combination is thus effected, and when the paste becomes too thick to stir it is framed and allowed to cool slowly for at least two days. This process involves some experience, and cannot be recommended to those who are novices in soap making. The main feature in the fabrication of these soaps is, to keep up the correct proportion between alkali and fat. It may occur, that a little too much or too little lye is applied ; because, on a larger scale the materials cannot be weighed or measured with the accuracy of an analytical test. But if HARD SOAP FROM POTASH LYE. Prior to the introduction of artificial sodas, the lye from wood ashes was extensively used for making household soaps, and for making hard soap it was the custom to boil in potash lye, and cut with culinary salt, either directty, or in solution. Where wood is burnt as fuel, and wood ashes abound and are cheap, or where potash can be procured economically, this process may possess interest and be of useful application, although at present in commercial centres this class of soaps is rarely made. Yet it is necessary, for the reasons stated, to give a-description of the processes. TALLOW CURD (GRAINED) SOAP. To transform 1000 lbs. of tallow into grained- or curd-soap, 400 lbs. of potash have to be taken. The tallow is placed in the kettle, about 400 lbs. of lye of 10° B. added, and the fire is kindled. Within a short time of the commencement of boiling, the fire is kept well up, but then it is moderated. After the seething up, examination should be made as to whether the fat has united with the lye. This is perceived by the yellow-brown mass, which under gradual upheaving continues quietly to boil. What adheres to the spatula, when inserted and withdrawn, has a gelatinous, grayish-white appearance, without separation of lye. When lye 310 TECHNICAL TREATISE ON SOAP AND CANDLES. THE FABRICATION OF SOAPS. 311 and fat are not united, it moves in the kettle noisily to and fro, without rising upwards, only now and then pushing up in single places, with a bouncing noise. The reasons why fat and alkali do not at first combine, are in general the same as are stated in the section on soft soaps, and the remedy is the same. When the combination succeeds there are added, at short intervals, in four to five portions, about 1100 lbs. of lye of 16° to 17° B. The boiling now becomes dense and languid, and the mass appears a yellowish-brown, and runs off the spatula in cohesive, long, translucent strings. The soap boils to a paste. If some of the soap is dropped upon a glass, and the sample while yet hot does not appear perfectly clear, lye is yet wanting. A small portion of lye should hence be added, until the soap while hot appears perfectly clear. As soon as this moment arrives the cutting of the pan begins. The salt has here a double purpose to fulfil. It must transform the potash soap into soda soap, and must separate it from glycerine, superfluous water, lye, and dross. The entire portion of salt necessary for this purpose is not added all at once, but a repeated " salting out" should be performed. After each " salting out" the under lye is separated from the soap, and the latter is again brought into contact with water and salt. Such an operation is termed by the soap-boiler a water, and he speaks of a first, second, and third water. By a boiling of tallow and potash, when the materials are not very impure, the " salting out" is performed usually in three operations, hence the soap is finished boiling in three waters. In order to separate the under lye from the soap, the latter is either scooped from the kettle into a vessel which stands close by the kettle, and afterwards the first is removed; or the soap remains quietly in the kettle and only the under lye is removed therefrom. This may be done in two different ways, either the kettle is provided below with a stopcock, or a pump with a movable barrel at its lower end is used. The salt is either thrown into the boiling soap " dry," or what is better, previously dissolved in boiling water, and used as a solution of 20° B. When the salt is used in the Previous Next
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