Wednesday, December 30, 2009
New self centering lightweight design
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!
Posted by The Slingshot Channel at 8:40 PM