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Old 04-05-2019, 06:26 PM   #6
popgun pete
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Join Date: Mar 2006
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Re: Slingshot Weapon with pulleys

I think too much drag for underwater use and using such skinny bands on the traverse it would thrum like a Lyre or a Harp, however there are maybe some ideas that could be used such as the travelling carriage that supports the front pulley frame. In some ways it is a rejig of the Arrow Gun which had a similar transverse roller frame at the muzzle, only the band ran right around the rear end of the gun and was under shields. I borrowed that rear band wrapping concept for the "Wiggler" cable gun and the bands never went around the muzzle rollers. On this slingshot gadget the pulleys are too big, but that is to make best use of the skinny bands which for terrestrial use are fine.

As for how it works the moving carriage cocks the bands and the bands are connected to the cable drive that propels the projectile which could be a dart or a ball bearing. The rearward set of pulleys control the cable run back to where it enters the stock and when it shoots the rearward rollers limit the forward travel of the drive cable. Being only small projectiles of low mass the drive stroke does not go right along the barrel as it appears to go only about half way. Note that the rearward set of pulleys travel with the muzzle carriage, they are all connected.

Many years ago there was a gun design that pushed the shaft with an impeller that had some mass to it and like this gun it had some extra pulleys about mid-way along the stock. The concept was the band propelled impeller pushed the shaft up to these pulleys and then the pulleys caught the bands which began to stretch as they decelerated the impeller gradually rather than the impeller crashing into a shock absorber. This made for a gun that was longer than the band drive stroke and its success can be gauged by it disappearing without any trace of its existence.

Last edited by popgun pete; 04-05-2019 at 07:00 PM.
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