# New "Backpack" self centering slingshot



## JoergS (Dec 17, 2009)

Hello,

I wanted to take the self centering design with hinges into a different direction today - the goal was to create a model that is very lightweight and fits well in a backpack.

First, I replaced the massive 12 mm stainless steel rods with 12 mm steel tubes. That stuff is a lot lighter, but of course less solid. So I had to give up the "W" form and go back to a classical "Y" design. This necessarily means that the super low fork of the "W" has to be given up some, you simply add 12 mm fork height. Still, a low fork is possible.

Next, I chose much smaller ball bearings, from RC controlled model cars. This allowed me to use a much thinner aluminum tube as a grip.

I kept the hinges because of the band life and also because they make the slingshot easier to be stowed away.

It works! The last "W" model weighs 800 gramms (almost two lbs), this one is just 200 gramms! 75% lighter.

I still prefer my full blown "W", but this self centers just as good and maybe the slightly higher fork has a psychological advantage for those who are afraid to hit their hand.

Wrapped the thin grip in nice, thick rope. I like it!




























Greetings from rainy Germany

Jörg


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## NightKnight (Dec 16, 2009)

I like it! Question; how do you get the rope to adhere to the grip? Do you use glue?


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## smitty (Dec 17, 2009)

I like it too! great weight reduction also!


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## JoergS (Dec 17, 2009)

I use epoxy glue. The ends, I burn them slightly so the plastic melts. Then, I press it against the grip with a wet finger.


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## mr.joel (Dec 21, 2009)

I also like it...two pounds, yikes! The original "W" is as heavy as an average autoloading pistol! The weight reduction is a necessary evil to make the design practical for hikers/backpackers/everyday carriers. Even with the weight reduction, it's a bit on the heavy side for a slingshot, still more than a pound?. But the extra weight is worth it I bet considering the advantages. If you used a high grade steel tube, like 4140, for example, and blued or browned it instead of using stainless steel you might counter the strength issues(if there are any). For hunters, stainless steel violates a fudamental rule of camoflauge and concealment anyway: shine. The aluminium also will shine, but could be dulled by anodization. Browned forks with a black anodized handle would look rather cool I think, as well as subdue the affair. Some other things to consider perfecting the final product.


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## mr.joel (Dec 21, 2009)

Alao, consider paracord that could be removed from the handle for added suvival value. You might add some kind of protrusion for a hole keep the cord in place? Or perhaps a leather strip wrapping? Many options here.


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## mr.joel (Dec 21, 2009)

Since you are still partial to your full blown "W," why not make a light version of it? Would the added tube really increase the weight so much that it wouldn't be worth bothering? seems a shame to comprimise your design.


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## JoergS (Dec 17, 2009)

Joel, the new lightweight model weighs less than a halfpound (200 g, 1 pound = 440 g). It is not heavy at all.

The "W" design requires solid steel. The torque is much, much greater because of the looong fork arms. Tube would bend when you draw out powerful bands. I could probably go to 10mm instead of 12, but not whole heartedly.

And actually I like the weight of the "W". It stabilizes the arm, simply reduces the shaking. Heavy means slow, slow means steady. It is just not ideal for going into the woods.


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## mr.joel (Dec 21, 2009)

The weight eliminates the shaking, hmm. Something to definately consider when you are talking about those hefty bands you use.


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