Slinging.org Forum - Rubber-band assisted sling

IronGoober

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Rubber-band assisted sling
Feb 12^th, 2021 at 5:07pm

Discussion here with various members and recent high(er) speed video of slinging releases has made me wonder if there is a way to get cleaner releases to reduce pouch wear, and reduce bad shots from poor pouch orientation.

I came up with the rubber band assisted sling. It requires a solid-pouch sling. A rubber band is fixed to the retention cord, wrapped behind the pouch and then fixed to the release cord at about ~ 8 cm down the release cord.

The aim is to store some elastic energy from the weight of the projectile and force of the wind-up, that will be released when the release-cord is loosed. This will pull the release cord out of the way faster, resulting in a cleaner release. But importantly, there is still no stretch in the main part of the sling, allowing for maximum energy transfer to the sling. For those of you that kept up this year, there was a lot of discussion about the "Y" sling and how clean its releases are. This rubber-band sling accomplishes something similar, but still results in spin of the projectile and you can still sling as hard as you like without early releases.

It seems to work. I took some 240fps video of a sling with and without the rubber band. The rubber band seems to pull the release cord out of the way a bit faster. Probably about 1-2 ms faster (each frame is ~4 ms). Top is with rubber-band, bottom without.

The only requirements are that the elastic isn't too strong. If it is, the weight of the projectile won't stretch the elastic far enough, and it tilts the pouch.

I think there is much room for improvement in the construction of this type of sling. But as a proof-of-principle, I think this did its job.

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« Last Edit: Feb 12^th, 2021 at 10:12pm by IronGoober »

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joe_meadmaker

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Re: Rubber-band assisted sling
Reply #1 - Feb 12^th, 2021 at 5:32pm

Awesome! Did you notice any shift in where you were hitting the target (until you were able to physically adjust) after putting on the rubber band?

Is there any difference in the feel of the release? When I did the video comparing a sling with normal paracord vs. one that had the paracord core removed, I was asked if I would be able to tell the difference if I didn't know which one I was holding. That's basically what I'm asking.

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Morphy

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Re: Rubber-band assisted sling
Reply #2 - Feb 12^th, 2021 at 5:44pm

For the record I just want to point out this is definitely one I wish I had thought of first.
Damnit

But seriously though i would love to see grouping averages and see if this makes a difference. I imagine it just makes a good sling even better at the very least and possibly might help with less than perfectly round stones on release? I can imagine it could increase short range accuracy at the which would be great for hunting. Long range is still going to have planing and elevation issues with the poorly shaped ammo.

Also, since I am throwing out random thoughts this is technically a spring assisted sling. In other words this is the switchblade of slings.

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Mersa Interfector Viris Spurii Offline Druid Posts: 2599 Australia Gender:	Re: Rubber-band assisted sling Reply #3 - Feb 12^th, 2021 at 5:44pm Great stuff, I’ve always thought about a assisted pouch.
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IronGoober

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Re: Rubber-band assisted sling
Reply #4 - Feb 12^th, 2021 at 6:26pm

@Joe There was a noticeable release to the right, as expected. But no large datasets to confirm. I think it would be hard to separate the human aspects from simply the sling. Though I suppose you don't really want to... You can't have a functioning sling without the person. Also, even if it is better on paper (i.e. theoretically) and it is a cleaner release, it could end up being a detriment rather than a benefit, just because of human limitations and/or prior training. I think one could adjust, however. It only takes about 2 - 3 shots for me to adjust to a new sling, whether heavier, shorter, longer, etc. So I don't think this is any different.

However, I don't want to screw up my timing by using this thing. I'm trying to simply get more consistent and I think throwing this into the mix right now will kill my progress.

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John R.

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SerKraus Senior Member Offline Slinging Rocks! Posts: 266 Gender:	Re: Rubber-band assisted sling Reply #5 - Feb 12^th, 2021 at 7:34pm Now that's what I call ingenuity!
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joe_meadmaker Slinging.org Administrator Offline Slinging Ice is Cool! Posts: 2922 PA, USA	Re: Rubber-band assisted sling Reply #6 - Feb 12^th, 2021 at 9:32pm IronGoober wrote on Feb 12^th, 2021 at 6:26pm: However, I don't want to screw up my timing by using this thing. I had a similar thought when I was using a Y-pouch for a little while.
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David Morningstar Slinging.org Moderator Offline Slinging Rocks! Posts: 3419 UK	Re: Rubber-band assisted sling Reply #7 - Feb 13^th, 2021 at 3:46am A while ago I wondered if a cord and weight attached to the release cord to pouch attachment point could help to offset the weight of the release cord and pull the pouch open faster. I never did anything with this, largely because I didnt fancy getting hit by the weight after each shot.
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AncientCraftwork

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Re: Rubber-band assisted sling
Reply #8 - Feb 13^th, 2021 at 5:01am

Irongoober have you studied how Luis throws ? It seems you are forgetting the final flick in the wrist to my eyes.
I find this final turning is essential. I think I saw Jaegoor doing it too. It makes the release spiral very clean and increases accuracy tremendously

He brings the sling forward like you are you doing, for a spiral release, than while he releases at the end of the throw, he produces a very sharp and quick turning of the wrist and forarm. This prevents the pouch from turning against the projectile like it does in your last frame photo.

It works for all slings in my experience, floppy and stiff.

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Archaic Arms

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Re: Rubber-band assisted sling
Reply #9 - Feb 13^th, 2021 at 5:09am

I think it was last winter that I tried putting an elastic band under the pouch of a seatbelt sling, so that it pulls the retention and release cord apart, and inverses the pouch completely. I didn't find it to be that useful when used in that way, as the elastic band is bent around the radius of the pouch pulling each cord downwards (when loaded). This means the elastic assistance for opening the pouch grows exponentially, so the amount of assistance to get the pouch flat isn't that much. What we want is a design that has a good initial force to open the pouch and pull away the release cord immediately at the point of release. The route I would take, is looking into materials one could use to make the pouch behave like a leaf-spring.
In terms on natural materials, any tightly braided fibre that has strong memory will do this. Sisal/pita is great in this way, which results in a very clean/fast.

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Lewis

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NooneOfConsequence

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Re: Rubber-band assisted sling
Reply #10 - Feb 13^th, 2021 at 1:16pm

That’s awesome IG. Simple and effective .

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IronGoober

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Re: Rubber-band assisted sling
Reply #11 - Feb 13^th, 2021 at 1:45pm

AncientCraftwork wrote on Feb 13^th, 2021 at 5:01am:

Irongoober have you studied how Luis throws ? It seems you are forgetting the final flick in the wrist to my eyes.
I find this final turning is essential. I think I saw Jaegoor doing it too. It makes the release spiral very clean and increases accuracy tremendously

He brings the sling forward like you are you doing, for a spiral release, than while he releases at the end of the throw, he produces a very sharp and quick turning of the wrist and forarm. This prevents the pouch from turning against the projectile like it does in your last frame photo.

It works for all slings in my experience, floppy and stiff.

Of course. His style fascinates me. I've probably spent hours looking at his videos frame by frame.

But if I look at mine, my wrist is similarly pronated (palm down) after the throw. Since the release of the projectile only takes ~16 ms (4 frames, 240fps), the position of the wrist when the projectile is loosed is the only thing that really matters. For any pronation/motion of the wrist to matter, it has to happen before release. I suspect Luis is similar to me (because of biomechanics) in that his pronation happens mostly after release.

The tipping of the pouch changes a bit depending on the style of sling, both the pouch and the retention loop. It is more rifled if I use a split pouch, and using a dual finger loop is better than a single loop. I've checked this using 240fps. Of course, this is just for me, other peoples' styles could end up with different results.

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John R.

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IronGoober Interfector Viris Spurii Offline ...and now, No. 1, the larch... Posts: 1601 California Gender:	Re: Rubber-band assisted sling Reply #12 - Feb 13^th, 2021 at 1:54pm @David I've also wondered about weights. I'll probably try it sometime if I'm feeling brave. @Albion Agreed. The leaf spring idea is a good one.
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Kick

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Re: Rubber-band assisted sling
Reply #13 - Feb 13^th, 2021 at 1:58pm

One of the slings I got from StoneHuevos for the SITH has some small washers attached to the release side of the pouch. It's detachable so I might well try out what sort of effect it has. Having very briefly tried with it attached, it opens very cleanly but I would need to do some more testing before I make any conclusions.

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IronGoober Interfector Viris Spurii Offline ...and now, No. 1, the larch... Posts: 1601 California Gender:	Re: Rubber-band assisted sling Reply #14 - Feb 13^th, 2021 at 2:03pm @Kick You should sling those papier-mache glands in the house and film it! chanting Do it, do it, do it.
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