A friend of mine asked me if I ever experienced failures. Yes, sir, failures galore! For every successful design, I have one that doesn't work.
He said that just showing off the successes is wrong, and asked me to present at least the more spectacular failures as well. OK, here are two of those.
The first one is an attempt to make a slingcat with draw length extension. The idea: A spring loaded mechanism would automatically raise a roller when you draw out, and then when you release it would snap back in, making room for the ball.
Problem is that it did not work. What happened is that the ball hits the roller. Obviously the roller did not get down fast enough. A dangerous slingshot. For the trash.
This next one was my attempt to make a target slingshot. I wanted adjustable fork width and height, self centering grip, a spirit level to avoid canting and adjustable sights.
In general it works, but it is way to heavy. I can make about ten shots, and then my arm begins to ache and to tremble. Plus, the adjustable fork height and width is unnecessary really. The only thing that is worth preserving is the sight+spirit level.