Page:Popular Science Monthly Volume 92.djvu/643

 �Q Amateur - Electrician

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��Electric Alarm Signal for Transmission Ropes

TRANSMISSION ropes in continual service eventually wear so that a break begins. The simple electric device

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���A broken strand in the rope strikes the wire and makes an electric contact

shown sounds an alarm as soon as the first strand breaks, or begins to unravel. Immediate repairs can be made before the break becomes a serious one that would necessitate a new rope.

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��To Prevent Leather Belts from

Slipping on Pulleys

N the machine shop, slipping belts are a source of constant annoyance, and tightening does not always remedy the difficulty. Powdered resin is bad for the belt, though unfortunately it is widely used. Its tendency is to dry and crack the leather. In place of resin, whiting can be used. Sprinkle it sparingly upon

��the inside of the belt. Continued use of this substance has demonstrated that it is the least harmful application. Resin is difficult to get out of the leather; whiting may be wiped off or washed out with water. The best results are obtained when the whiting is applied once a week. A frequent cause of slipping is the failure to lag the iron pulleys with a covering of leather. If this detail is attended to, it will, to a great extent, do away with slipping.

Mounting a Porcelain Base Electric Light Receptacle

EXPERIMENTERS and students who are using porcelain receptacles for experimental and practice work, find that they very often break off the porcelain lugs which are used to hold the receptacle to the wall. A very good and cheap method of eliminating this waste is to mount the receptacle on a piece of 3^^-in. fiber, 3)^ in. by 3 in., \vith 8-32 machine screv/s, as shown in the illustration. The two holes in the corner of the fiber base are used to hold it to the wall, taking the

��� ��With the fiber base attached the porce- lain socket is protected from breakage

place of the holes in the porcelain. In this way, the receptacle is guarded against breakage. — Walter B. Weber.

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