Page:Popular Science Monthly Volume 91.djvu/310

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294

��Popular Science Monthly

��A Turned Down or Pistol Grip Handle for a Garden Rake

THE straight handle on a rake makes it difficult to grasp when drawing it over the ground, especially where the heap of rubbish to be moved is large and long. To make a better hold for the hand I attached the turned down handle or grip as shown in the illustra- tion. A similar grip makes a broken handle on a garden tool as good as new. To apply the grip, cut a shoulder about 3 in. from the end so that the tenon will fit into a hole bored in the prepared grip. The grip is made of a block of hard, even- grained wood, cut to the shape shown. A long wood screw passing through the grip and into the rake handle will make it rigid. — Frank L. Matter.

���A curved grip attached to the end of a rake handle

��A Tool for Accurately Lining Shop Shafting

IN many shops where machines are belted from lines of shafting little attention is given to the alinement after the shafting has once been lined up unless the settling of the building, the weight of the pulleys and the tension of the belts make it so badly out of line that attention is called to it by the thumping and heating.

Often shafting is so little out of line that it will show no sign of its condition although it will turn so hard that it will require much more power than it should to turn it. The usual test of throwing off all belts and trying the shaft by hand is not always reliable as the strain of the belts may change the alinement, and a section of shafting not perfectly straight may not show by that test, but may cause trouble when run at speed.

The method described is a certain, practical and economical way of lining new shafting or of testing an old line of doubtful alinement. It can be applied in small spaces between belts and pulleys and will give dependable results of both the vertical and lateral alinement at one setting of the fingers. It is a great advantage to test a line of shafting while it is under the condi- tions of the tension imposed by its belts and pulleys, as a very tight belt midway

��between two hangers may spring a section of the shafting. This will cause trouble which may not be detected by any test made with the belt off the pulley.

The method is based upon the fact that when the center lines of two cylinders form a perfectly straight line in their relation to each other, two points, one upon the surface of each of the cylinders, will be exactly the same distance apart when the cylinders are turned.

The fingers fastened as closely as prac- ticable to the ends of adjoining sections of shafting enlarge the diameters of the shafting and make possible the application of this principle with sufficient accuracy to prove whether the two sections of shaft in question are in perfect alinement.

It is evident that the longer the fingers the greater will be the degree of accuracy possible to attain, though in many cases fingers which will permit the shaft to turn completely around will give sufficiently accurate results, as the shaft can be tested both above and below and on each side.

The fingers may be made roughly, for it is immaterial whether they are perfectly square with the shaft or not, as their relation will be the same if each is firmly fastened upon the shafting. They may be held in place by a clamp or by a bolt as

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���Wood arms attached to the ends of both shafts to determine the accuracy of the lining

indicated by the sketch. Care is necessary in measuring the distance between the fingers in their different positions, and in adjusting the shafting so the distance will be exactly the same in whatever position the measurement is taken.

In lining a new shaft by this method several pairs of fingers may be used at once to save changing, in which case the middle section should be correctly lined and the rest of the shafting lined both ways from it. — Charles A. King.

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