Tapered flat band max elongation

 Precise is one of the market leading slingshot band manufacturers. In their website, at the product description they write: "5 to 6 times the super tensile strength, safe and stable." We can consider this, 500%...600% as the recommended maximal safe elongation range. 

Tapered bands are wider at the fork end and narrower at the pouch end, so they are stronger at the fork end, weaker at the pouch end. When we pull the band, the elongation will be higher at the pouch end.

How much is the TOTAL elongation, when the pouch end elongation is in the middle of the factory recommended range?


Test description
I cut a band from 0.6mm Precise elastic, 18/12mm taper. 180mm long. I fix its narrow end to the bench. I draw a thin line 1cm far from the fixing block, and another line at 16cm. 



Then I pull the wide end until the pouch end elongation is 550%, and read the total elongation. Then I pull further the wide end, until the pouch end elongation is 600% (safety limit). Then I read the total elongation again.

Test results:

- At 550% elongation at the pouch, I measured 500% total elongation.
- At 600% pouch end elongation (safety limit) the total elongation was 525%.







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