This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
Anyone who has ever played tennis will readily see the advantage of the net-tightening device shown, in preference to the old method of pulling the net tight by hand. All that is necessary to make the device is 1 ft. of ordinary gas or water pipe, 8 or 10 in. of 1/2-in. iron bar, and two twenty-penny nails. The posts generally used are 6 by 6 in. About -A in. from the top of the post bore a 1-in. hole, parallel with the direction the rope is to run. On the inside surface of the post bore four 1/4-in. holes.
Drill a 1/2-in. hole 1 in. from one end of the pipe, and a 1/4 -in. hole 1 in. from the other end. Put the iron bar in the 1/2-in. hole, tie the rope around the pipe and bar at A and wind. With the leverage of the iron bar one can readily pull the net to any desired tightness. After the net is drawn in position, put one of the nails through the 1/4- in.hole in the pipe and the other in one of the 1/4-in. holes in the post. - Contributed by Wm. S. Looper, Gainesville, Ga.
Ill: Tightener on Post