I tried searching and didn't see anything recent that followed this line of thought; if I missed something feel free to point me in the right direction!

Practical Paracord's Week 10 Online Slinging Competition had a brief discussion about the possibility of having some type of competitive slinging "power" measurement.  IronGoober mentioned a pendulum, but I couldn't think of an inexpensive way to log how far such a pendulum would swing to accurately gauge between competitors. 

Here's a concept for a target that I drew up today.  Instead of a hanging pendulum, the target is mounted to a sleeve on a flagpole, closet rod, pipe, etc. and rotates parallel to the ground.  Using a shaft collar above the sleeve with index marks at 45 degree locations and a matching index mark on the sleeve, one could count every 45 degrees of rotation as 1 point.

The materials would be (in Imperial sizes for now, I didn't have time to research the metric equivalents and draw it accordingly):

*1-1/4" PVC pipe tee (Slip on with a Threaded outlet)
*(2) 1-1/4" PVC pipe, 12" long
*(2) 1-5/16" shaft collars (one custom engraved, which I would be able to supply since I work as a machinist)
*(2) 1-1/4" 2-position Conduit clamps
*20" Heavy duty aluminum pizza pan
*1-5/16 diameter closet rod (or 1-1/4" steel pipe, etc.) 72" long
*1-1/4 x 24" long threaded PVC pipe nipple

This would keep the costs low enough that anyone should be able to build one.  The stand post could be either sharpened to pierce the ground, or one could buy an umbrella spike to mount it to the ground. 

I'll try to get the renderings uploaded below; hopefully they aren't too large.

Hoping to get some feedback and start a discussion.  As we know, slinging is basically balancing accuracy and power.  There are competitions and challenges for accuracy, and challenges for power (like the pumpkin challenge), but having a measurable way to compete with power (and accuracy, I suppose) could be a fun way to expand the hobby a little more.

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I like the idea but usually anything that requires people to purchase things or build things get put behind other challenges. Hell people complain they don’t have any soda cans to try can challenge.

Now power is a hard one to measure, on peeper a pendulum is a simple solution but there’s gonna need to be restrictions put in place otherwise we’re not just measuring one thing.

Transfer of energy is one issue. Some stuff will transfer energy better that others. Including how it’s mounted and supported.
Projectile mass is another. Joe might just sling a few cannonballs and spin the target out of orbit.

I think if we all had radar a speed slinging challenge would be cool . And if we can figure out a solution for power that would also be nice.

Again like other challenges, participants are hard to come by.
I know a few people might have time to build a setup but I feel some regulations need to be discussed.
Then again there’s no prize so if people just wanna wack a pivoting disk I’m super keen to watch

Es gibt ähnliche Ziele im Schießport

Mersa wrote on Jan 9^th, 2022 at 5:53pm:

I like the idea but usually anything that requires people to purchase things or build things get put behind other challenges. Hell people complain they don’t have any soda cans to try can challenge. Now power is a hard one to measure, on peeper a pendulum is a simple solution but there’s gonna need to be restrictions put in place otherwise we’re not just measuring one thing. Transfer of energy is one issue. Some stuff will transfer energy better that others. Including how it’s mounted and supported. Projectile mass is another. Joe might just sling a few cannonballs and spin the target out of orbit. I think if we all had radar a speed slinging challenge would be cool . And if we can figure out a solution for power that would also be nice. Again like other challenges, participants are hard to come by. I know a few people might have time to build a setup but I feel some regulations need to be discussed. Then again there’s no prize so if people just wanna wack a pivoting disk I’m super keen to watch

I'm with you there, Mersa.  I'm planning on building this target and putting it up on Youtube, so maybe we can get a few other takers to give it a shot.

I agree that the projectile can make a big difference; Joe slinging ice balls would have more energy than the typical guy slinging a tennis ball.  But picking a standard projectile would help, like tennis balls, with standard distances and the like.  Basically like you're saying; minimize the variables so that it just comes down to how hard the projectile hits the target so that it's an even comparison.

I like the design.  Looks like a great target!

I do have a thought.  Because of additional leverage, won't a target hit that is farther away from the pole register as more powerful than another hit (at the exact same speed) that's closer to the pole?  I'm not sure how that would be prevented though while still keeping a relatively good sized target.

Perhaps a triangle so shots with more leverage need to be more precise

I think a triangular target could make things really interesting if a game was made from this.

But the bigger concern wasn't that someone would be targeting the outside edge.  The problem I'm thinking about is it could be difficult to compare one slinger's results to another.  I think you would need a camera really close up so the exact position of the hit can be seen.  And the other slinger would need to hit the same spot for the results to be compared.  Even doing it that way would a have certain amount of error involved.  Whether the error would actually matter or not will depend on how precise the target is.  It the rotating arm is pretty tight, the difference of a few m/s might not change the position enough to see it.

There’s gonna be variables that you can’t control.
If everyone uses identical ammo and an almost identical target then I think having a small amount of accuracy involved is kinda a good thing.

I think the main issue with going sideways on the pendulum is having a consistent brake. With a normal pendulum, the brake is gravity, so you should always get the same amount of swing for the same momentum transfer, no matter where the hit on the pendulum. But for a sideways pendulum, the dynamic friction of the pendulum rotation may change with differing speeds of rotation, so a hit on the near vs far edge may cause different amounts of rotation for the same momentum transfer (because a hit on the close edge will make it rotate faster than the far edge). Not to mention, even with using the "same" materials, the friction can be different and the local conditions can change friction (i.e. humidity and temperature). 

But besides those points, and I emphasize this, it is still a good idea and will be fun to try. I think that if the results are too close to call between separate people's shots, who cares? just shoot again.

There is definitely a way to make a normal pendulum with your same setup and mark how far it swung. You just have to have a collar that has a one-way catch that the pendulum will only move when it swings one direction, and the collar needs enough friction to stay in place. I haven't built one, but I also know that PVC is not the best choice for slinging targets. It can be brittle and doesn't survive impacts well.

This is from over a decade ago, but I don't think PVC has changed much.
https://youtu.be/fnyQI3pgN8Q?t=96

IronGoober wrote on Jan 11^th, 2022 at 11:28am:

This is from over a decade ago, but I don't think PVC has changed much. https://youtu.be/fnyQI3pgN8Q?t=96

I forgot how incredibly satisfying that hit is (for me not having to replace a broken target stand and just watching from home on my computer :D)

joe_meadmaker wrote on Jan 10^th, 2022 at 3:59pm:

I like the design.  Looks like a great target! I do have a thought.  Because of additional leverage, won't a target hit that is farther away from the pole register as more powerful than another hit (at the exact same speed) that's closer to the pole?  I'm not sure how that would be prevented though while still keeping a relatively good sized target.

I had the same thought today; I kinda kicked around the idea of a target that is closer to the size of a tennis ball, which would require accuracy and would minimize the margin of error. Would be a LOT harder to hit though

IronGoober wrote on Jan 11^th, 2022 at 11:28am:

I think the main issue with going sideways on the pendulum is having a consistent brake. With a normal pendulum, the brake is gravity, so you should always get the same amount of swing for the same momentum transfer, no matter where the hit on the pendulum. But for a sideways pendulum, the dynamic friction of the pendulum rotation may change with differing speeds of rotation, so a hit on the near vs far edge may cause different amounts of rotation for the same momentum transfer (because a hit on the close edge will make it rotate faster than the far edge). Not to mention, even with using the "same" materials, the friction can be different and the local conditions can change friction (i.e. humidity and temperature).  But besides those points, and I emphasize this, it is still a good idea and will be fun to try. I think that if the results are too close to call between separate people's shots, who cares? just shoot again. There is definitely a way to make a normal pendulum with your same setup and mark how far it swung. You just have to have a collar that has a one-way catch that the pendulum will only move when it swings one direction, and the collar needs enough friction to stay in place. I haven't built one, but I also know that PVC is not the best choice for slinging targets. It can be brittle and doesn't survive impacts well. This is from over a decade ago, but I don't think PVC has changed much. https://youtu.be/fnyQI3pgN8Q?t=96

I agree, and the idea of a horizontal pivot was not my first choice. After seeing some of the initial comments, I decided that for me personally (being a machinist) I'll make a prototype out of steel tubing with ball bearings and test it. My thought is that if we can get low enough friction to get a few rotations, then at 8 points (45 degree graduations) per revolution we would start seeing some disparity in power (and therefore scores) if the target is reasonably small.  I'll have some new renderings of a new design later this week, and I may make a few extra prototypes for those who would be interested.

IronGoober, with your power arm you would be an excellent candidate haha

Machinists you say???
Well have I got some projects for you!!

Mersa wrote on Jan 12^th, 2022 at 5:19am:

Machinists you say??? Well have I got some projects for you!!

Haha, shoot 'em my way!  deucedohbro@gmail.com is my email address so we don't clutter up the thread

IronGoober wrote on Jan 11^th, 2022 at 11:28am:

I think the main issue with going sideways on the pendulum is having a consistent brake. With a normal pendulum, the brake is gravity, so you should always get the same amount of swing for the same momentum transfer, no matter where the hit on the pendulum. But for a sideways pendulum, the dynamic friction of the pendulum rotation may change with differing speeds of rotation, so a hit on the near vs far edge may cause different amounts of rotation for the same momentum transfer (because a hit on the close edge will make it rotate faster than the far edge). Not to mention, even with using the "same" materials, the friction can be different and the local conditions can change friction (i.e. humidity and temperature).  But besides those points, and I emphasize this, it is still a good idea and will be fun to try. I think that if the results are too close to call between separate people's shots, who cares? just shoot again. There is definitely a way to make a normal pendulum with your same setup and mark how far it swung. You just have to have a collar that has a one-way catch that the pendulum will only move when it swings one direction, and the collar needs enough friction to stay in place. I haven't built one, but I also know that PVC is not the best choice for slinging targets. It can be brittle and doesn't survive impacts well. This is from over a decade ago, but I don't think PVC has changed much. https://youtu.be/fnyQI3pgN8Q?t=96

You make a good point, IronGoober. When built by the individuals, it might allow too much room for too many additional variables from the materials. If I can get a good prototype made and can work out a process to keep the costs down, then I could minimize that variance by using machined components and could produce them for those who would be interested (putting the cart before the horse a bit, but you get the idea).

I am liking what has been commented so far; the next revision will have a smaller disc (probably about 8" or 200 mm) on a much smaller frame to minimize the difference between shots placed on the outer edge of the target versus those places on the inner edge. I'll do the best I can to keep the center of mass as close to the axis of rotation as possible so that any hit has a better chance of generating several turns (the higher the turns, the easier it will be to determine differences in impact power; 8 full turns could be 64 points, 7-1/2 turns would be 60). More than likely, I'll include a bullseye (for aiming, not scoring) toward the other edge as well. I get paid this week too, so I may start building this guy and putting up some build and testing videos on YouTube within a week or two.

Okay, so I sat down this evening and drew up another, smaller idea.  This one has an 8" disc and is about 24" tall to the top of the shaft.  I got permission today to pick through some of the material at work, and I'll be ordering some laser cut plates. 

This design has a counterweight that balances the rotating assembly, so it will be harder to get it moving because of the extra mass but it should stay rotating longer because the mass is concentric to the axis.  With the crosshairs cutouts in the target plate, it should help reduce air drag a little.  This whole design is steel, with a three-pronged spiked stand that is driven into the ground to anchor it.

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Looks awesome. Man I wish I had access to all the stuff your showing off.
Could make some awesome targets

Cool idea.  Friction is always going to be a challenge on a rig like this, but if you design in bearings and a separate braking mechanism you’ll get more consistent results… that may be splitting hairs too early though.  The best thing to do is build it, try it, learn from it, and then build it again based on lessons learned.