How to Make a Pole From Coiled Steel
- 1). Define the age group for which you want to have a climbing coil pole. According to figures compiled by the Center for Disease Control, a child 12 years old and 4 feet tall is an average 80 pounds for boys, depending on stature. Since they grow a little faster at that age, the average girl is slightly taller than boys that age and weigh about 5 pounds more, depending on stature. These rough figures can vary significantly.
- 2). Determine a safe number of children climbing a coil spring pole at the same time.
- 3). Assume five average weight and height children climb the spring simultaneously, at about 85 pounds each (according to the CDC figures for 12-year-olds), and the wire diameter at 1 1/2 inches thick, 70 coils high with a center-to-center coil diameter of 3 1/2 inches (normal pole size). With these figures, the spring could absorb the weight of 2,125 pounds of shock weight without moving. If all the kids were to jump up and down simultaneously, you need a spring capable of handling almost 30,000 pounds of force. To be on the safe side, and assuming the worst jumping imaginable, you would need a spring coil diameter of 2 4/5 inches and have plenty of pole resistance to withstand the shock force.
- 4). With the same scenario in step 3, but without the spring coil diameter greater than 3 1/2 inches, decrease the center-to-center coil diameter to a thinner pole-like dimension of 3 inches, which would accommodate 10 kids jumping up and down and the coil would still act like a pole.
- 5). Determine the degree of safety you want to build into your coil spring pole and obtain the size you feel most comfortable with, using a spring-weight calculator. Play around with the numbers until you feel comfortable with the width of the coil spring, its diameter and any other safety considerations you care to include.
- 6). Sink the spring into at least a 2-by-2-foot concrete foundation. Common sense and your level of comfortability determines the size and depth of the concrete foundation of the spring pole. Add the depth of the pole to the size spring you want exposed. For example; if you want a 5-foot climbing spring pole and want to anchor it in 3 feet of concrete, you need 8 feet of coiled spring.
- 7). Dig the appropriate-sized hole, place the spring in the center at the bottom of the hole and fill with concrete. Allow several days for the concrete to set and cure before using the pole.
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