If possible, the surfaces to be glued together should be heated to 212° F., as the glue can then be slowly applied. The thinner the layer of glue in cementing together smooth surfaces, the better will it adhere. But a somewhat thicker layer is required for rough surfaces, for instance, boards not planed, the excess of glue being forced out by strong pressure. Generally speaking, it is best to subject all articles cemented together with marine glue to as strong a pressure as possible until the glue is congealed.
Repeated experiments have shown that with the aid of this cement square vats perfectly water-tight can be constructed of boards. Wooden pegs dipped in the compound should be used for putting the vats together.
Jeffrey’s marine glue. Dissolve 1 part of rubber in benzine, and mix the solution with 2 parts of shellac by the assistance of heat.
Another formula is as follows: Coal naphtha 1 quart, rubber cut in shreds 2 ozs. Macerate for 10 or 12 days and then rub smooth with a spatula on a slab; add 2 parts by weight of shellac to 1 part of this solution. To use the compound melt it at about 240° F.
Marine glue for damp walls. Rubber 10 parts, whiting 10, oil of turpentine 20, carbon disulphide 10, rosin 5 and asphalt 5. Dissolve the ingredients in a suitable vessel and stand in a warm place, shaking it frequently.
Scrape the wall smooth and clean, and apply the glue with a broad brush on the damp place and about 8 inches higher than the line of dampness. Before the glue is dry lay on plain paper which will adhere tightly. On this plain paper the wall paper can be pasted in the usual manner. If carefully done, the wall paper will always remain dry.
GUTTA-PERCHA CEMENTS.
Cement for leather. Gutta-percha 100 parts, pitch or asphalt 100, oil of turpentine 15.
This cement should be used hot. It is suitable for cementing all kinds of substances, but adheres particularly well to leather.
Cement for hard rubber combs. A. Prepare a very thick solution of bleached gutta-percha in bisulphide of carbon.