How much material is in the elastic tube?

It is obvious: Thicker rubber generates bigger force. If you use flat bands, it is easy to calculate the area of the flat band (see my drawing) area=width*thickness. (If the flat band is tapered, you have to use the width at the middle.)

If you would like to pick an elastic tube, which has similar strength, you have to calculate the area of the cross section of the tube. Elementary school geometry. It is actually the difference of a large circle and a small circle. You can find the formula in the drawing.

For example, if you pick 1632 tube size (1.6mm inner diameter, 3.2mm outer diameter) then the area of the cross section is cca 6 mm^2 (square mm). If you use 0.5mm thick flat band, then a 12mm wide one will be similarily strong. Similarily. This is a very complex issue in reality, it is easier to measure. You will need a fishers' digital scale for that. I think, all the serious slingshooters must have one.



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