Hi all, I'm new to the forum, and new to slinging.
Based on what I've read, it seems most staff slings use a rigid staff. I was curious about using a springy staff. I figured it might allow the user to put more energy into the early part of the throw, flexing the staff, and get that energy back right at the release. My experience suggested that flexibility in fishing poles helped with longer casts. So I tried it!
I just made my first staff slings and tested them out. I'm very lucky to live in a rural area with plentiful wood, stones, and space to play in. I used small green willow wood to make my staves. My first staff didn't flex very much even with heavy stones. Most of my throws went 100' or so, I was slightly disapointed, I wanted at least 3x that range. The second staff flexed a lot with stones the size of a plum and hurled them 100 yards no problem! It could hurl smaller stones far as well, but didn't work right for stones much bigger than a plum.
My conclusion is that the springy staff is way better!
http://postimg.org/image/lu2g3t483Both staffs are between 5' and 6' long. The larger one is 7/8" thick at the top. The smaller (better) one is 1/2" thick at the top. The sticks taper naturally to almost twice as thick at the bottom. The same sling was used for both using 8" of bicycle inner tube and 30" or so of paracord. I experimented with shorter lengths of cord and left the excess attached.
The first one used a notch and stopknot release, then I switched to a loop release. The notch release has at least one major advantage and one disadvantage. The advantage is it's much easier to adjust the length of cord. I tied several stopknots in the release cord, and adjusted the fixed cord by coiling it around the staff. This approach worked fine... at least the terrible power and accuracy I was getting were not noticeably worse. The disadvantage of the notch release is that it takes more damage if the tip of the staff hits the ground after a throw.
I experimented with three different throwing styles. 1) Wood chopping style, exactly as one would use a splitting axe. This style sucked on power, it is possibly the easiest way for a beginner to lob a stone 100', but it is just a lob. 2) Rainbow style, this involves keeping both arms extended and swinging them in a full arc from right to left while twisting the hips. This style gave the most power to very heavy stones, but was hard on my back. 3) Fisherman style, this starts off almost like the wood chopping style, but instead of sliding the top hand down the shaft, one breaks both wrists at the top of the arc moving the top hand forward while the bottom hand pivots in place. This style had by far the most awesome range and power when slinging stones the size of a plum or smaller. For larger stones I was unable to do it.
I should also mention that sticks have a natural direction they prefer to bend. To find it, just stand the stick vertically on the ground and push down at the top. The stick will naturally always bend in the same direction. Align the cords (and notch) with that.