Page:Popular Science Monthly Volume 89.djvu/432

 Safeguarding the Sand Blaster

��At Left, the Hopper Where the Workman Operates. A Strong Suction Saves the Sand and Draws Off the "Flour" So Dangerous to the Lungs

The Head-Dress Allows a Free Passage of Air About the Head and Through the Fine Copper Gauze Which Protects the Eyes. The Hands Are Heavily Gloved

���THE preparation of metal surfaces for a covering of paint lias gi\-en rise to the extensi\e use of sand blasting outfits. When these are con- structed of sufficient capacity to accom- modate large surfaces such as are pre- sented by automobile guards, hoods and bodies, the problem of protecting the workmen presents some difficulties.

I'"inc quartz sand is si)rayed agair.st the metal surfaces, causing a certain amount into a powder as fine and volatile as flour. This sand flour is very jienetrat- ing, and many ingenious devices in the form of head-dresses are now in use to protect the face and lungs of the opera- tor. The familiar helmet with its s]ionge through which the operator breathes is ada|)te(l for this inu'iiose. On account of the cutting i)roperiies of the sand, glass cannot be used, and the sub- stitute is an exceedingly fine copper gauze giving the necessary range of \ision.
 * )f disintegration of tJie i)arliclcs of sand

Such devices are only partially suc-

��cessful from the standpoint of protec- tion, and can only be relied upon when built in the form of a diver's head-dress and supplied with fresh air imder pres- sure. Operations were first conducted to co\er the larger detachable sheet metal automol)ile j^arts such as dust shields, fenders, hoods, etc., and after many experiments, the device, as illustratetl, has successfully solved the jiroblem.

The container is of the familiar hopper type, with a strong suction both o\er the top and underneath, carrying only the hea\'\' particles of sand Hour to the bottom of the hopper, where they are collected and again drawn through the air-suction liose. In this way the sand is used o\er and o\er again, and onh' the Hour is drawn off. Fresh sand is introtluced through the large door at intervals, each unit caring for its own s.ind sujipK". The work is introduced by

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