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I joined your refreshingly adult forum yesterday. I design and make in a modest way in Portugal.

When I first made and shot slingshots many decades ago (catapults to us Brits) the best I could get in the UK to power them was ¼" elastic. Thousands of shots never once gave me a flier, let alone a fork strike.

Back into the scene a handful of years ago and having exhausted cheaper models as poorly made, lack-luster and toyish, I bought a proprietary board-cut slingshot (at no small price) and thus entered the OTT flatband scene. Initially, I was captivated by the sheer energy and speed of the flatbands, and all was well.

Soon though, weird things start to happen. Despite my meticulous loading and shooting, I could not predict or avoid fliers or fork strikes, and 30 or 40 shots later, the mono-directional ply gave up and split. I was truly at a loss to explain the problem. Sure, the board used was not like a true plywood employing opposing grains as used in the aircraft or marine industry. And sure, the fork widths designed to support 1" wide bands offered a prodigious target for a fork strike, but why did this happen?

I set about my own design at great length. I employed materials specific to need (I am a retired aircraft engineer) aluminum for the forks and woods for the handle.

Proud of my prototypes I found the same problems. OK, I had no breakages because of the comparatively slim metal forks - but I still got fliers. No fork strikes due to slimmer forks, but nevertheless, fliers.

I was perplexed and indeed tore my limited hair out for some days. Then I started to do some research about this phenomenon on the net. I eventually found some info and a youtube clip about the rotation of the pouch. I followed the advice and was rewarded with an instant cure. No matter how you hold the fork, upright or gangster style, 9mm steel or 55 cal lead, provided that you introduce a 90 degree twist - clockwise or counter-clockwise - to the pouch, the problem goes away. Not once, but every time (I hold in the left hand and prefer a 90 degree rotation clockwise - thumb on top).

Now I'm sure that many of you guys out there know this already but my question is this:

1. Is this a characteristic of flatbands?
2. Is this to do with OTT systems?
3. Is it something else? (the Footloose catapult is not an OTT sling)

To discover the source problem, I videoed about 40 shots with the intention of viewing the slow-mo dynamics of the band and released shot. The camera I have is not the best kit but I can see the trace of one shot leaving slightly above the 'shoot through' forks. This may be due to the vertically held forks abruptly dropping following the release, I don't know, but it did not help me with a reason.

All I can say with certainty is that with the Footloose catapult, a 90 degree twist in the pouch is essential for reliable shooting. And I mean reliable. Shoot without this twist and fliers will result. Shoot with a twist and you are on the button every time.

What I need is this: Someone with a really good video camera to record a meaningful number of flatband shots in both shooting modes - the pouch held in a plane with the forks, and a pouch held at 90 degrees to the forks.

BIG NOTE
Please don't anyone refer to asymmetry of band length or yaw of the forks! I can demonstrate that this idea is an urban myth (on film) (as soon as it stops raining here). I can wrap an accurately cut flatband around one fork and still hit my target without having to compensating for the shot. The phenomenon I am seeking to unravel above is nothing to do with asymmetry!

Thanks for your protracted attention, Footloose
 

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Now I'm sure that many of you guys out there know this already but my question is this:

1. Is this a characteristic of flatbands?

As far as i know, no. Twisting the pouch can be done with any bands to avoid forkhits.

2. Is this to do with OTT systems?

Dont think so.

3. Is it something else? (the Footloose catapult is not an OTT sling)
As far i know, forkhits are a result of canting you're fork and/or poor release.
 

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Part of your problem may have to do with what I call the speed bump effect. You can try this simple experiment. Hold your fork vertically, handle down, fork tips toward the sky. Draw back a loaded pouch, holding the pouch with your thumb clamped on your index finger. Twist your pouch hand so the thumb nail is pointing up. Bend your pouch hand upward at the wrist, so that your index finger is elevated. The pouch and ammo will be behind your index finger, clamped by your thumb. Fire the ammo by just pulling your thumb back toward yourself. The pouch will be dragged over your index finger and will bounce upward, and your ammo will fly high. This is what happens when you go too fast over a speed bump in the road with your car.

When you are using bands with a fairly heavy pull, the natural tendency is to clamp the pouch in front of the ammo between your thumb and index finger, with the ammo in the pouch resting just behind the index finger. Thus if you are not very careful with your release, you are likely to get the speed bump effect.

So, suppose you do not twist the pouch, but your pouch hand is canted slightly and/or you release by just lifting your thumb. You will get the speed bump effect, only it will throw the ammo to one side, causing a fork hit and a bad flier. To get a proper release, you need to keep your wrist straight and do one of two things: 1) smoothly move both thumb and index finger equally, or 2) relax the tension on your thumb and index finger gently, letting the band pull the ammo in the pouch from between the thumb and index finger, rather than from behind the index finger.

These are just suggestions which may help you diagnose the problem. By all means, keep us posted on what you find.

Cheers ..... Charles
 

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363 Posts
That is my experience too. Too strong bands that cause you to pinch in front of the ball. Bad pouches and sloppy ammo placement also play a big role. For my first slingshots I used pouches that were far too short and far too stiff, with a too small center hole and I got no end of fork hits (dinged up a really nice Chinese stainless steel frame, still hurts when I look at it). And that was with the pouch twisted. I always twist because I only shoot target style with the ss in a horizontal position and holding the pouch upright feels most natural.

But I do not believe twisting has any effect on fork hits whatsoever, except for pickle fork shooters maybe where you apparetly kind of rely on the speed bump effect. I haven't shot one yet, though.
 

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So if I understand, twisting the pouch disguises the real problem of "bending" the pouch by having the recovery from bending happen on a different axis?
 

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So if I understand, twisting the pouch disguises the real problem of "bending" the pouch by having the recovery from bending happen on a different axis?
Precisely. The speed bump effect is not always objectionable ... when the bump lofts the ammo over a shallow or no-gap fork, or over your fist, it is serving a good purpose. But if it lofts the ammo to the side, or downward, it is likely to result in disaster. For example, see this thread on bare back shooting:

http://slingshotforum.com/topic/20079-bareback-my-way-explained/

Cheers .... Charles
 

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"Mighty Can Smiter"
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4,302 Posts
If you don't want to click on the above two links here is a link that explains it perfectly LINK


Other than that, it appears others have explained it already.

LGD
 
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