I constructed the slingshot found in my profile picture from a rubber tie-down strap, two robertson wood screws, and a piece of exercise equipment for excerising the forearm. <br><br><br>This is an interesting slingshot to use. The fork is a hand and forearm exerciser. When these are squeezed together they release rapidly under spring tension. This Compromises the grip slightly but it also pulls on the bands as the forks expand accelerating them forward. This is beneficial.<br><br><br><br>I pull this slingshot hard closing the fork all the way. Then I release allowing the forks to expand and the band to release, firing a penny through the rapidly expanding opening. Using a tension spring at the base of the fork is a substantial improvment for other reasons including acting as a power guage for pulling back the bands. Pulling back a band of a certain quality will cause the spring to compress a certain amount which can be used as a standard measure.<br><br><br><br>I would like to see Jeorg use such a slingshot that has a springloaded expanding grip mechanism and a band, as it stretches the band as it expands upon release.