I love this idea truly. I am just really confused about the goal. Please correct me if I'm wrong. You want to build up power in the sling then at the point of release have that power transfer to the projectile. This would give you more umpf! behind a lighter object. The power generated by the heavier weght is used as an extra kick while the weight itself never leaves the sling. This however does not prevent you from swinging the sling because you still have generate the initial power.

I'm sorry if thats all wrong, my reading comprehension not so good. I have toyed with weighted pouches. I have taken weights and attached them to the underside of pouches. I set them up so they hung on a cord in the exact center of the pouch abou two to three inches long. Looked like decorations. I found this to help a lot with lighter stones. The weights help to open the pouch quicker too. I think because the weights are on the outside, when you let go the pouch rips open. My main reason for adding the weights was to make the sling a useable weapon even without ammo.

NOTE: I started this post, then drew the picture, then posted it, and only then did I see Yurek's post.  His drawing is better, because he shows how the sling is used.

Dork, after reading what you wrote, I do not think you got Matthias's idea.  He has a two-part sling.  If I built one of these (which I will probably do, so if all of a sudden I disappear from here you will know I killed myself with the monster) -- anyway, my version of this design would look something like the attached sketch.  I would hold the cords in my hand, and also hold the pouch and ammo in the same hand.  Then I wind up like I was going to sling the booster weight, but at just the right time I let go of the pouch and it swings out and up and the ammo flies off into the sunset.

Of course, the more probable result is that the cords tangle and I bash my own head in with the booster weight.

I think it should be mentioned that THIS IS AN ADVANCED SLINGING PROJECT AND SHOULD NOT BE ATTEMPTED BY BEGINNERS! (Good grief, so what I am explaining it for?  We are all crazy around here! Excuse me, I have to go build a sling...)

Alright! Here's hoping that Dale comes back and lets us know that a. he's ok and b. he managed to test the sling. Dale's drawing is basically the "manual release" option. The problems I had were (somehwat predictably) the timing (fast fast fast), holding three things at once, and slack in the secondary. I'm sure that there is a neat wrist-flick trick to solve the last problem - how many tries does it take the average slinger to figure a figure-8? This won't necessarily come easy! If it could be made to work it is by far the most attractive option to me personally - the purist approach.

A sliding release... I'll have to think about that one (resisting urge to put one into the simulator) At first glance, I don't think that it will give you enough time for the pouch to come around. It might also be pretty hard on your hand if it slid any distance (no pinky loops, remember) The _good_ news is that it might just put the booster out of danger range, allowing you to ground out a failed throw!

I'm glad we've had a healthy ratio of in this thread. It might be that these things are puppy dogs, but the odds aren't good until we figure out some of the kinks...

I don't know where all of this head-bashing fear is coming from I'll offer odds on left-leg charleyhorse followed by kneecaps, and of course the general groinal area...

Matthias

dork - your descripition is pretty much on, but the power boost in the compound comes from the motions that two connected slings work through. Weighting a standard sling might provide other benefits (accuracy, light ammo, loud noises) but it can't accelerate the pouch the way this one is supposed to.

There is no way you are ever going to get the release timing right, if the pouch is anywhere near Mach 1.0!!  You are going to have to perfect the automatic release.

I might as well jump in here.

I think the problem of timing and dealing with the release of multiple parts of the sling (release of the projectile restraint and release of the projectile from the sling) could be solved by an intelligent release mechanism.

I'm thinking of a pistol grip like device that has two catches on it.  You could have two separate buttons on it (I'm thinking a trigger to release the projectile from the sling and a thumb button to release the projectile portion of the sling).

You would then have a sequence something like:

1.  Start Swing
2.  Swing
3.  Thumb Release
4.  Continue Swing
5.  Trigger Release
6.  Projectile Launched
7.  Duck because the booster weight is going to smash you in the face.

It just seems really hard to pull this off by manually releasing these sequentially.

Not one to hijack a thread I just thought of throwing this out there.  I was inspired a few weeks ago about making a 'rubber' sling.  Remember those sticky rubber hands you had when you were a kid?  Yeah the ones that would melt if you left them in the car too long?  You could really get those things moving back and forth.  Well, I think designing a sling that has an elastic snap to it could add additional punch to the sling.  The sling would be swun in an eliptical pattern and the projectile launched while the the sling is snapping back into shape.  I have thought long and hard about what materials to use, but the only things I really come up with could be difficult to shape into a sling (the gel from inside computer arm rests come to mind, I saw a video once of a 1 ft long gel pad interior being swung back and forth and deforming approximately 15+ ft and snapping with great force).  Sorry for the side track.

I believe that the best solution for the issue of timed secondary (or final) release, is to simply not have one at all. This is one advantage to Yurek’s design, since you do not need to attempt to time a second release. I.e. once the initial pouch is released the booster mass will automatically trigger the final release of the ammo.

I believe one way to do that for matthais’s design, is incorporating the concept similar to what was proposed in the innovators nook…
http://slinging.org/forum/YaBB.pl?num=1079645737

The way that would be done is as follows bellow… for simplicity’s sake, imagine that the booster mass has a flat head, (and I apologize for the horrible diagram, but it was the best I could do)…

Basically, the release cords are longer then the retention cords. However, because the release cords are attached to the corner furthest away when the pouch is in your hand, the ammo is balanced in the pouch. But once the pouch is released and as soon as it reaches a point directly on top of the booster mass, the ammo will slide out from the side of the release cords.

Shihab

I am not sure it can be done either, FunSlinger.  But Matthias and Jurek have talked about it quite a bit and both think it might work.  I am game to try!  But mine is going to use something like a tennis ball for the booster weight, and maybe a squash ball for the ammo.  I am NOT risking my skull, or kneecaps, or potential descendants, on the chance that this will work first time.  I figure I am going to get tangled up in the rig quite a few times before I know if it is workable or not.

Oh, the desired goal?  Sheer raw SPEED!  If this gadget works, it is going to release at twice the velocity of a standard sling, maybe even more.  The Guinness world record is within my grasp! (assuming they can be talked into accepting it as a "sling", and Engvall convinced them that a metal dart was a "stone" so I have a fair chance).  Of course, I will have to get my rig working before Jurek gets his working, or I've got NO chance of making the record book.