cements, rubber and guttapercha

Значение термина cements, rubber and guttapercha в knolik

1. In making a cement one should know pretty thoroughly what is to be expected of it before they could advise upon it. For instance, an ordinary rubber cement will hold on a host of different surfaces and with the best of success, except where there is continued dampness. For holding to damp walls, or surfaces where there is a constant pressure of moisture there is nothing equal to Jeffrey's marine glue, the formula for which has been published and republished all over the world. It consists of - 1 part rubber, 12 parts coal tar, and 2 parts asphaltum. The rubber, after having been massed, is dissolved in the undistilled coal tar, and the asphaltum is then added. This glue, as its name indicates, is oftentimes used for mending articles at sea, or patches, for instance, that are to be laid on surfaces that are to be under water, and it has been found to be a most excellent thing.
2. A guttapercha cement for leather is obtained by mixing the following. It is used hot. Guttapercha, 100 parts; black pitch or asphaltum, 100 parts; oil of turpentine, 15 parts.
3. An elastic guttapercha cement especially useful for attaching the soles of boots and shoes, as on account of its great elasticity it is not liable to break or crack when bent. To make it ad here tightly, the surface of the leather is slightly roughened. It is prepared by dissolving 10 parts guttapercha in 100 of benzine. The clear solution from this is then poured into another bottle containing 100 parts linseed oil varnish, and well shaken together.
4. Davy's universal cement is made by melting 4 parts common pitch with 4 of guttapercha in an iron vessel, and mixing well. It must be kept fluid, under water, or in a dry, hard state.
5. A very adhesive cement, especially adapted for leather driving belts, is made by taking bisulphide of carbon 10 parts, oil of turpentine 1 part, and dissolving in this sufficient guttapercha to form a paste. The manner of using this cement is to remove any grease that may be present on the leather by placing on the leather a piece of rag and then rubbing it over with a hot iron. The rag thus absorbs the grease, and the two pieces are then roughened and the cement lightly spread on. The,two pieces are then joined, and subjected till dry to a slight pressure.
6. A solution of guttapercha for shoemakers is made by taking pieces of waste guttapercha, first prepared by soaking in boiling water till soft. It is then cut into small pieces, placed in a vessel, covered with coal tar oil, tightly corked to prevent evaporation, and allowed to stand for 24 hours. It is next melted by standing in hot water till perfectly fluid, and well stirred. Before using it must be warmed as before, by standing in hot water.
7. A cement for uniting rubber is composed as follows: 100 parts finely chopped rubber, 15 of resin, 10 of shellac; these are dissolved in bisulphide of carbon.
8. Another rubber cement is made of 15 gr. rubber, 2 oz. chloroform, 4 dr. mastic; first mix the rubber and chloroform together, and when dissolved the mastic is added in powder. It is then allowed to stand by for a week or two before using.
9. An elastic cement is made by mixing together and allowing to dissolve the following: 4 oz. bisulphide of carbon, 1 oz. fine rubber, 2 dr. is in glass, ½ oz. guttapercha. This cement is used for cementing leather and rubber, and when to be used the leather is roughened and a thin coat of the cement is applied. It is allowed to completely dry, when the two surfaces to be joined are warmed and then placed together and allowed to dry.
10. Cement used for repairing holes in rubber boots and shoes is made of the following solution:
    1. Caoutchouc 10 parts, chloroform 280 parts. This is simply prepared by allowing the caoutchouc to dissolve in the chloroform.
    2. Caoutchouc 10 parts, resin 4 parts, gum turpentine 40 parts.
    For this solution the caoutchouc is shaved into small pieces and melted up with the resin, the turpentine is then added, and all is then dissolved in the oil of turpentine. The two solutions are then mixed together. To repair the shoe with this cement, first wash the hole over with it, then a piece of linen dipped in it is placed over it; as soon as the linen adheres to the sole, the cement is applied as thickly as required. (' Chem. Trade Jl.')

Рядом со словом cements, rubber and guttapercha в knolik