Throwing a disc vs. throwing a stick

[Blake_T1]

a while back Brad Walker had brought up the idea of throwing a disc like a hammer or a stick.

this concept definitely simplifies things since the human body is wired with the knowledge of throwing such objects and brings the idea of throwing a round and flat object closer to that.

after some discussion with people as well as using objects like pens/sticks to help people find the natural stopping points and resulting angles involved in elbow/wrist extension etc. i started thinking about it in a slightly different way than how Brad had shown in his video (the one with the painted disc).

if you are curious about this, pick up something like a pen, pencil, stick, etc. and use a motion somewhat similar to your disc golf motion to fling it in a straight line with as much force as possible. this gives a very realistic idea of the appropriate angles/positions of the arm/wrist/shoulders in order to throw a disc with a lot of snap.

however, i came up with a revision on Brad's teaching method that i feel is a bit easier to visualize/grasp in terms of the relevant position of the disc in the throwing motion.

basically, it's this:

while you are still throwing the outter edge of the disc, the motion used to fling the stick would line up more closely here... which is more of the front edge of the disc as it trails behind the plane of the "stick."

 

[Parks]

Interesting.

Side note: Nice tourney pro Cyclone.

 

[Widdershins]

Maybe if you superglued the pen to the disc as seen in the photo it would stick in the chains better.

Ok, I have an unrelated questions (unrelated to the topic although related to my joke) for Blake T, seeing as he is a scientific sort of guy. Does any kind of plastic (or hardness of plastic) actually stick to the chains better? And does a soft or hard putter have a greater chance of bouncing off the post and out of the basket?

 

[jubuttib]

Ok, I have an unrelated questions (unrelated to the topic although related to my joke) for Blake T, seeing as he is a scientific sort of guy. Does any kind of plastic (or hardness of plastic) actually stick to the chains better? And does a soft or hard putter have a greater chance of bouncing off the post and out of the basket?

Go check out the ION thread over at the equipment section. It's a putter with a candy plastic type core and an overmolded super sticky rim. At least the people in that thread are convinced it grabs the chains better than anything else and goes in even on throws where other discs would've just bounced out. The overmolded rim also seems to absorb hits and the putter bounces way less from tree hits etc. People also like as a driving putter. They're pretty ga-ga over it.

I also feel that my P-Line P1 putter (basically soft and tacky R-Pro material) grabs the chains better than my other putters.

 

[some call me...tim?]

Hmmm, I think there may be something to this. I tried holding a sharpie like in the pic, gave it a fling, and shanked it hard right into the schule of my apartment.

 

[Timko]

Blake, after seeing Brad talk about the 'hammer,' I've been doing exactly what you've shown in the picture to describe and show spin to noobs.

 

[emiller3]

I'm dense, what am I look at in the picture?

 

[Blake_T1]

Ok, I have an unrelated questions (unrelated to the topic although related to my joke) for Blake T, seeing as he is a scientific sort of guy. Does any kind of plastic (or hardness of plastic) actually stick to the chains better? And does a soft or hard putter have a greater chance of bouncing off the post and out of the basket?

well, my philosophy on it is this:
i don't want a putter that will "grip" chain. i don't want a putter that behaves viscous against chain.

if you rate softness on a scale of 1 to 10, with 10 being a blowfly and 1 being one of those as hard as porcelain firm wizards, i would favor putters in the 4-6 range.

if you rate grippiness on a scale of 1 to 10, with a 10 being a blowfly and 1 being one of the old vinylish elite z putt'rs, i would favor putters in the 4-6 range.

putters that are soft/grippy will pick up an extra 2" or so on the high right side but at the same time, anything above 6" above the basket that hits even 1/4" left of the center of the pole will have a tendency to grip and spin out.

putters that are too stiff/slick will have a great tendency to cut through and/or riccochet/redirect on chain contact.

ideally, the putters that will have the greatest makeable surface area on a basket are ones that are of a softness and grippiness that will slow down upon chain contact but will simply "spin in place" against the chains while the friction against the chains will slow down the spin without having the spin cause the putter to move laterally against the chains. with these types of putters, fairly extreme left/right putts within 6" of the top of the basket will kick downards and tend to stay in. putts that miss slightly left will tend to drop down rather than spin out. you lose a bit on the high right but pick up enough around the pole to more than cancel that out.

in terms of bouncing off the pole, a super stiff putter has a higher chance of bouncing off pole than a less stiff putter. but a super soft putter has a higher chance of spinning off the pole when it hits. i recommend a happy medium.

i made a picture contrasting a medium stiffness medium grip putter on the left vs. a really soft high grip putter on the right. the color represents an approximation of the makeable surface area.

basically, you can think of it being like a kc aviar vs. jk aviar, hard magnet vs. soft magnet, hard soft wizard vs. soft sss wizard, etc.

 

[Blake_T1]

I'm dense, what am I look at in the picture?

throw a pen/pencil/stick using something approximating a backhand throw. make sure you snap it firm/straight (it may take multiple tries). when you get a "good one" look at the angle of your elbow and your wrist. those are the approximate angles you will have if you try to "hit" a disc.

the arm will be slightly bent (although mostly straight). the wrist will be very open.

basically, it shows if you were to throw a disc the same way that you threw the stick, it's not all that different.

 

[JHern]

Ok, I have an unrelated questions (unrelated to the topic although related to my joke) for Blake T, seeing as he is a scientific sort of guy. Does any kind of plastic (or hardness of plastic) actually stick to the chains better? And does a soft or hard putter have a greater chance of bouncing off the post and out of the basket?

well, my philosophy on it is this...

I agree entirely with everything Blake said. If you want to add a little more science-yness to it, here goes...

You initially have a putter traveling with speed v and mass m. Also, the disc has a moment of inertia I and spin rate w. The kinetic energy of the putter is:

Ek=1/2(m*v*v + I*w*w)

After the disc comes to rest in the basket, and all of the chains have stopped moving, v=w=0. According to the law of conservation of energy, Ek is transformed into another kind of energy, because the disc no longer has any kinetic energy. Where does the energy go? It goes into what we like to call "dissipation." Dissipation turns mechanical energy into heat energy by raising the temperature of the substances involved in the interactions with the body that had kinetic energy to begin. If all these bodies (basket+chains+disc+surrounding air) have a collective heat capacity C, then the average temperature of these things after the disc comes to rest is increased by Ek/C.

Friction, like that between a chain and a disc, can be a form of dissipation. But only if it is the right kind of friction. There is static friction, which is when two object's contact areas are stuck together. And then there is dynamic friction, when there is relative motion at the contact interface. Friction dissipation only happens when there is relative motion (i.e., sliding) between the two contact areas, i.e., for dynamic friction. If they are stuck together, with no sliding (static friction), then there is no dissipation.

Plastic that is overly grippy tends to promote static friction, without sliding. This isn't good, because it will not dissipate the disc's kinetic energy. Plastic that is overly smooth will slide at the interface, but there will be little resistance force between it and the chains, so that even though there will be dissipation it will be small. The "sweet spot" is right in the middle: grippy enough to exert resistance to sliding, but not so grippy that there is no sliding whatsoever. I.e., 4-6 on Blake's putter grippiness scale.

The most important form of friction in a chain basket is the friction between the links of the chains. This is why it is a great disc stopper. It is admittedly crude (other threads can be perused for more info on why that is the case), but the contacts between links of a chain seem to provide enough dissipation to catch a well-thrown disc. If you want a basket to catch discs better, then figure out a way to get more friction dissipation between the links.

 

[Blake_T1]

cool. any mr. wizard-esque comments on soft putter (with lots of flex on impact) vs. stiffer putter?

it would be interesting to see which dominates, the grippiness of the plastic failing to dissipate or the bending on impact of a soft disc...

personally i prefer discs that flex a tiny bit but not much because i find floppier discs tend to flex and recoil before they leave my hand... which i figure cancels out any benefit in terms of chain interaction because it's harder to get a consistent release.

 

[JHern]

cool. any mr. wizard-esque comments on soft putter (with lots of flex on impact) vs. stiffer putter?

it would be interesting to see which dominates, the grippiness of the plastic failing to dissipate or the bending on impact of a soft disc...

personally i prefer discs that flex a tiny bit but not much because i find floppier discs tend to flex and recoil before they leave my hand... which i figure cancels out any benefit in terms of chain interaction because it's harder to get a consistent release.

When a continuous body deforms, there are two kinds of response: elastic and plastic. Elastic deformation is recoverable, i.e., if you bend it, the body will bounce back to its original shape. Plastic deformation is permanent, i.e., if you bend it it will stay bent and not return to its previous form. Elastic deformation is accompanied by very very little dissipation. Plastic deformation is all dissipation. So the perfect putter character is one that you can only throw once, it'll be all mashed the first time it hits the chains.

Of course, we don't use plastic deformation one-use disposable putters, so there will be little dissipation from that property of the putter. The key then is time scale. A more floppy putter will rebound slower than a more stiff putter after hitting something. If the floppy putter rebounds back to its original shape on a time scale that is similar to half the natural period of the pendulum motion of the chains, then the rebound of the putter shape will add to the back force of the chains swinging back from the initial impact, and may well help to push the disc backwards and make it less likely to drop in the basket.

So a stiffer putter seems better, with middle-of-the-road friction. Of course, we can't rule out the possibility that a putter can be designed which has properties that increase the dissipation in the chains, but I can't think of a straightforward way to do that.

Another quick thought with respect to stickiness of the putter: you don't want the disc to spend too much time stuck against the chains, you want it to drop, before it has the opportunity to swing back out. This is another reason to avoid super sticky rubbery putters.

I guess somebody should tell Vibram. :lol:

 

[JHern]

Back to the stick...

a while back Brad Walker had brought up the idea of throwing a disc like a hammer or a stick...i started thinking about it in a slightly different way...while you are still throwing the outter edge of the disc, the motion used to fling the stick would line up more closely here... which is more of the front edge of the disc as it trails behind the plane of the "stick."

A question: Is the idea about the head of the hammer still the same? I.e., that we should imagine that the head of the hammer is out at the tip of the pen? I guess this is more or less a question about where we should imagine the center of mass of the object to be.

 

[Bradley Walker]

Very good!!!

I think it would be easier to feel the pen if you slid an eraser on the end.

 

[jubuttib]

I guess somebody should tell Vibram. :lol:

And MVP.

 

[Blake_T1]

A question: Is the idea about the head of the hammer still the same? I.e., that we should imagine that the head of the hammer is out at the tip of the pen? I guess this is more or less a question about where we should imagine the center of mass of the object to be.

heh, honestly, i've never thrown actually picturing the disc like a hammer.

it's more conceptual than anything. there was a while back where people were nitpicking tiny angles and positions (mostly due to spending too much time with still frames and slow motion) and throwing a pencil/stick really shows those angles.

as for center of mass, i personally would think of the edge of the disc behind where the pen cap meets the pen.

 

[ericlagstein]

I'm not sure if this is related... but does spin equal distance?

I was fiddling in the backyard, and when I tried to "fling" the hammer/or stick, I seem to throw with a lot more spin... not sure if this is a result I'm trying to learn from this...

Is spin one of the goals?

 

[jubuttib]

Well, spin should help keep the disc level longer, hence delaying fading out at least... So yeah, it's probably part of the equation, but not everything. Every time I saw my friend throw around 380-400' when we first started to snap my jaw pretty instantly dropped because the disc just flew so much faster than before.

 

[Star Shark]

It would seem to be a balance of speed and spin. As you know, many discs need more speed to fly appropriately. Spin helps mainly in the event of glide but if you're getting a proper ejection there, it will increase your baseline speed a bit. The trick is maintaining good arm speed/acceleration while getting good snap on it.

 

[JHern]

When you increase speed, usually you also increase spin. The two go hand-in-hand with respect to the throwing mechanics, and grip strength.

Something fun: I learned an interesting thing a while ago, watching some extreme throws and analyzing the possible explanations for the late-late-turn some players can get. Basically, the spin rate, when it starts really fast, slows down in flight at a faster rate than does the speed (specifically, the ability for spin to stabilize it slows more quickly than the ability for speed to make the disc turn). Since high spin stabilizes the disc from turning or fading (precessing right or left for RHBH, respectively), the lower spin rate later in flight while still at higher speed causes the disc to turn more rapidly later on.