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.
By J. H. SANFORD
THE popular roller coaster that furnishes untold amusement for the multitudes that patronize amusement parks during the summer can be easily duplicated in a smaller way on a vacant lot or back yard for the children of the home; or the boys of a neighborhood could contribute to a fund and construct quite an elaborate affair, on the same lines as described, for the combined use of the owners. The one described was built with a track, 90 ft. long, 5 ft. high at one end and 3 ft. at the other, the track between being placed on the ground. In coasting from the high end to the low one, the coaster will run up on the incline, then drift back to within 24 ft. of the starting end. The car was built to seat four children or two adults. The cost of all the materials for building this roller coaster did not exceed $10.
Ill: Inexpensive Back-Yard Roller Coaster, Suitable for the Enjoyment of the Young as Well as the Older Persons
The track is of simple construction and requires but little description. It is necessary to have it straight and nailed firmly to the crossties on the ground and to the trestles where it is elevated. The ties and trestles are placed about 6 ft. apart. The two trestles for the starting platform should be set so that there is a slant to the track of about 6 in. for starting the car without pushing it. The car can be carried back for starting by adults, but for children a small rope can be used over the platform to draw it back on the track, or a small windlass may be arranged for the purpose.
Ill: Detail of the Car, Wheels and the Trestle, Which is Attached to a Tie
The main frame of the car is 3 ft. long and about 13 in. wide, firmly fastened at the corners. The axles for the wheels are machine steel, 19 in. long, turned up on the ends and threaded in the manner of a bicycle axle to fit parts of bicycle hubs, attached to the main frame as shown at A. The wheels are solid, 4 in. in diameter and 1 in. thick, and are set on the bicycle cone of the ball cup, after they are properly adjusted, and securely fastened between washers with a nut on the end of the axle. Guide wheels, B, are placed on the sides in the manner shown. These wheels are ordinary truck casters, not the revolving kind, 2 in. in diameter.
About 1/2 -in. clearance should be provided between the guide wheels B and the guard rail C, on the track. When the car is made in this manner it runs close to the track and there is no place where a child can get a foot or hand injured under or at the sides of the car. The one described has been used by all the children, large and small, for a year without accident.