THE HANDY MAN’S CORNER.

Otago Witness, Issue 3912, 5 March 1929, Page 10

THE HANDY MAN’S CORNER.

A REVOLVING LAWN SPRINKLER.

(Special for the Otago Witness.)

Prolonged watering at regular intervals during dry weather is an essential requirement for any lawn, if it is to be maintained in perfect condition. Much time and labour is expended in watering from the ordinary garden hose, moreover the volume of water, and the force at which it is delivered is unnecessarily great. Most of these defects are overcome by the use of a portable rotary lawn sprinkler. A simple type of such a device (shown in Fig. 1) can be made by any handy man, and costs only a few shillings for materials. The principle on which it operates is quite simple; the water is delivered through a garden hose to a tee piece at the base of a short vertical pipe, the lower end of which is closed by a screw plug. The water then rises up the centre pipe and through two apertures into a circular shaped box, which is free to rotate around the pipe. Four short pipes project from the box, and have at their outer ends an elbow and a small-bore nozzle. The water rushes out of these nozzles, and the reaction causes the arms to revolve, thus throwing the jets of water over a large area, and in so doing breaking them into fine spray.

At the bottom of the central pipe is a flange with four metal feet attached. This supports the device and makes it possible to move it from place to place. The materials with which the sprayer is made comprise four pieces of gas barrel 9in long, one piece for the central pipe gin diameter loin long; four Jin elbows, four brass nozzles to screw into the elbows; one gin tee piece, one gin gas flange, one gin nipple, one gin brass tap with hose pipe connection; four pieces iron bar 9in long, lin wide, gin thick. All of the foregoing can be had from any ironmongers, who may also be able to supply one circular four-way distribution box with central lead, as used in electrical wiring systems. This

is required for the revolving head, and is a standard electric fitment, one type of which is shown in Fig. 3. These fittings vary a little in detail, some have two reffiovable covers, others have a. solid base, with a central hole and boss. They are generally to be had with four bosses or screwed holes which will do very well for the arms to fit into. Ask the ironmonger to screw the holes with a Jin

“ iron gas ” thread, corresponding with that on the arms. Also have a fin diameter hole drilled through the centre boss, or the middle of the bottom plate on the distribution box. Make up the revolving head by screwing the four arms firmly into the screwed holes, then screw the elbows B (Fig. 4) on to the outer ends of the arms A, setting them so that they all point in the same direction, and also point upwards about lodeg, and screw the nozzles, as at C, into the elbows.

The next proceeding is to file up the outside of one end of the central pipe until it fits quite easily into the central hole in the box, and can turn perfectly freely therein. File two V shaped slots across the pipe, and then drill a jin diameter hole at right angles and through the pipe, nearly at the end, fit a brass pin F (Fig. 3) into it, and drill and tap a hole in the centre of the brass pin, so that a fixing screw, as at E in Fig. 2 will screw into it. This screw must be “ shouldered ” that is it must have a solid part a little larger in diameter than the screwed part, and extending from the head for a distance of about £in. The collar B (Fig. 2) is made by filing away the screwed part of the connector supplied with the pipes, pushing it on to the central pipe, and fixing it with a small set screw as shown in the sectional drawing. This collar should fit against the underside of the revolving head C, when the top plate D, and screw E are fixed. The sprayer arms are shown at G, the central pipe at A, in Fig. 2, which is a sectional view of the complete device. Note that one or two felt and metal washers are placed under the screw head to make the joint reasonably watertight. A hole to suit the size of the shoulder on the screw has of course to be drilled in the middle of the top plate. The lower part of the device is easily assembled, the tee piece being screwed to the end of the pipe, and the top screwed into the arm or branch part of the tee piece. The nipple is screwed into the lower end of the tee, and the flange then screwed on to the nipple, and the hole closed by a screw plug. The four metal feet are then drilled, and riveted to the flange, for which purpose it must be similarly drilled prior to assembly, unless the flange is already provided with suitable holes. Lubricate the bearings with ordinary vaseline, and then finish the whole by a couple of coats of high-grade paint and one of enamel.