To remove scale from drop forgings which have to be machined, dip in a pickle composed of hot water 24 parts, sulphuric acid 1 part. Hardener.
To write black on glass or bright metal, use 1 to 2 parts of silicate of soda with 10 parts of India ink. Write with a steel pen. F. H. Jackson.
Angelica, N. Y.
Saturate a cotton string in kerosene, wrap it around the glass tube where you wish to have it cut, set fire to the string, and when all parts are ablaze, plunge the glass in a pail of water. Give the top of the glass a light blow with a stick, and there will be an even break all around. Detroit, Mich. Charles Sherman.
It is often very desirable to remove chips of steel from jigs and the like each time a new piece is inserted. An easy way to do this is to put a pound of caustic soda in a gallon of water and dip the jig in every time it is desired to remove the chips.
Winnetka, Ill. F. Pavlik, Jr.
To remove grease, paint, etc., from machinery add half a pound of caustic soda to two gallons of water and boil the parts to be cleaned in the fluid. It is possible to use it several times before its strength is exhausted. F. Pavlik, Jr.
In brazing in place of spelter use wire or rod brass and boracic acid as a flux. Anneal the end of wire or rod by heating, while the joint is getting hot, and after dipping the rod into boracic acid, apply to the joint, the rod melting at the end will flow into the joint. After the joint is cooled, submerge in hot soda water; this will take off every particle of acid, leaving only the brass to be filed off. F. H. Jackson.
Angelica, N. Y.
An experienced blacksmith has used for years the following in welding steel springs. Just before the steel comes to a welding heat he placed a small piece of Russian sheet iron - such as stove bodies are made of - on the joint; this melts and runs into the joint so that the weld is perfect. X. Y. Z.
A good compound for welding cast steel is made as follows: 41½ parts, boracic acid; 35 parts, common salt; 20 parts, fer-rocyanide of potassium; 7½ parts, rosin; 4 parts, carbonate of sodium. Heat the pieces to be welded to a light red heat and apply above compound, then heat to a strong yellow heat and the welding may be accomplished in the usual manner.
The usual precaution applies, of course, in the use of the above, the same as with any of the cyanides, and that is to avoid breathing the poisonous fumes. A. A.
Many machinists ride their bicycles to and from work and are consequently interested in anything that will make tires more nearly puncture-proof. I have not tried the following anti-leak compound, but infer from a note in the English Mechanic that it works successfully on both single and inner-tube tires. Mix ¼ pint of silicate of soda (water glass), ¼ pint of commercial glycerine and a large tablespoonful of rubberine; inject about a teacupful into the tire. If too thick, a little water can be mixed with it to thin it. If rubberine is not available use powdered rosin.
M. E. Canek.