How to adjust spin vs. speed

[Bradley Walker]

the "average" disc golfer releases around 12:30 with big arms closer to 2 o'clock.

More disc pivot.

The more pronounced the pivot, the later on the clock the hand will be at release.

Newbies throw the front of the disc, good players throw "the other side of the disc". This creates a slinging that results in the hand coming around the nose and releasing much later.

 

[Blake_T1]

there's a lot of myths about speed vs. spin. it's often cited as the case for why discs fly understable for sidearm throwers. if they concentrate on spinning it rather than velocity, they flip less.

the problem is that most sidearm throwers generate tons of OAT, and by "concentrating on spinning it" they remove OAT and focus on keeping their flick on plane with the disc plane. while the "attempt to add more spin" may have fixed the problem, it's not the spin that fixes it.

there was a time when i struggled throwing putters/mids for distance backhand and attempting to add more spin seemed to fix things, but in the actuality of it is that i just removed OAT.

It is possible to reduce speed and get a much higher amount of spin relative to speed by shortening the reach back and retarding the onset of hard acceleration of the arm. It does have real world dg applications such as avoiding flipping and lessening fade for some discs, not speedy ones, like in penetrating gaps and driving with putters and longest mid flights.

the thing is with shortening the reach is that it's basically the bent elbow technique. the first portion of this is basically "how to throw with snap" moreso than how to remove speed and increase spin.

They did not calculate speed they used several high speed cameras shooting at 280 FPS measuring velocities both linear back to front speeds and angular velocities. Velocities were measured from several places including elbow, wrist, center of the back of the hand and center of the disc.

the problem that i have with this is that all velocities are moot except for the disc velocity after release. i've seen tons of people who can generate 70mph of arm speed, but only a handful actually get 70mph of disc speed AFTER it leaves the hand. what i struggle to believe is that it's possible to maintain the same launch velocity with slips, micro or otherwise.

I was talking about Joe average no big snap getting _relatively_ closer to pro disc speeds easier than to pro spin rates. In absolute terms both categories leave ams lacking big time in most cases. I too mentioned earlier that speed to spin manipulation is doable at low speeds and not so well at full power.

i don't believe this is true though. most guys throwing under 430' line drives have launch velocities under 50mph. if you measure a 300' throw, the velocities are likely relative similar if they are throwing the same discs, but on max D throws, joe average is likely 10-25mph slower than mr. top pro. i would wager that both are getting spin rates under 20 RPS.

overall though, i don't even think about spin anymore. it is possible to have some manipulation of flight characteristics with spin changes well within your power range, but i find it much more consistent to manipulate flight characteristics with intentional OAT since it doesn't affect launch direction or force transfer.

what i would give warning to are the guys on here who are not huge snap throwers attempting to manipulate spin and trying to cite that as the reason for the flight changes. velocity, nose down, and the force plane are responsible for the majority of flight characteristics.

 

[Moseley]

The master thesis JR is mentioning can be found here: http://www.tbgfrisbee.no/Tips/hovedoppgave.pdf
It's in norwegian though so even a Finn might have trouble reading it correctly (no offense JR ), technically more adept people than myself might be able to read something out of the tables and such I guess.

As far as I can understand, Carlsen finds most correlation between exit velocity of the disc and 1.rotational speed of the hips, 2.minimum elbow angle/max speed in elbow extension, and 3. disc rotation.
So, imporant things to practice would be footwork, elbow chop, disc pivot. I think Blake, Bradley et al should find much to like here

One of the ideas I found interesting, is how the subject with the highest disc speed holds on to his disc with both hands during reachback, Carlsen theorizes that this might help him in delaying shoulder rotation (his rotational speed peeks just after the hit while some of the others are de-accellerating at this point) and therefore be beneficial. i find it very plausible since coming through to early with your shoulders seems to be a commom problem - maybe grabbing your disc with both hands leads to a breakthrough in timing and after that it becomes an unneccessary crutch? I would suspect the habit of pointing your disc towards the target just before the x-step has a lot of the same function (adjusting rotational timing, but this might help someone with weight transfer timing as well).

Another interesting aspect is how Carlsen concludes that the best training would be leg and core muscles since he really can't show much effect from strong-arming at all. For instance, all subjects show almost no change in shoulder/upper arm angle, and even though elbow extension is one of the most important elements, this is thought to be mostly a result of prior movement (too quick to be conscious).

What strikes me when reading ths and other threads, Blake, is how you have an ability to look beyond the first explanation that comes to mind, and if there is no certain knowledge to look at all possible factors before forming an opinion as to what is the most plausible explanation. Since DG is dominated by teaching based on personal experience, it's just the kind of critical thinking that's needed.
Not to insult anyone else here, but I find the arguments for people actually manipulating spin - not angle, speed, oat etc - are not very convincing so far...

 

[JR]

I agree with most of what Blake wrote. I'm not promoting intentional slipping as a good way (the opposite in fact) to do things just a possibility. In fact I don't recall ever having to decrease spin because I've managed well using conventional techniques. I've experienced OAT removal as a byproduct and the primary reason of improving things myself.

The way I've reduced reach back length isn't what I think of traditional bent elbow style. My definition may be off.

There's footage of Avery Jenkins shot obliquely from above me and mafa captured on video and mafa edited at youtube. My Xcaliber spun at approximately 20 revolutions per second thrown by him the footage is originally 300 FPS played back at 29.97 FPS. I don't know if mafa changed anything in that during editing. You can make your own measurements to confirm or debunk that number. If you want the unedited footage I filmed I can put it up to a file sharing site so that you can download it, examine and measure it. The measured disc has a color bar in the middle thrown backhand. The disc is worn and it flipped. How hard and well Avery threw is something that must be asked from him but he did flirt with 500' all the time during the video shoot. Rather consistently. I haven't measured the speed but those were no Joe Public 300' drives either

Again without checking my recollection of the thesis my memory was that the speed of the disc was also displayed after the rip somewhere. The thread where I translated the thesis in the most interesting parts with non existent skills in Norwegian with the disclaimers presented there about why I'm somewhat able to pull the
translation off (a Norwegian member understood less of the thesis) are in the thread http://www.discgolfreview.com/forums/viewtopic.php?f=2&t=4019. Wyno can you check my translation and what kind of language skills in Norwegian or related languages do you have because I loathe misrepresenting anything but don't like having a correct translation of mine tainted by another interpretation that is wrong?

The measurements showed IIRC that the launch velocity was about 10% faster than disc velocity at elbow straight wrist bent. Wrist unbending and the lower body parts combined generate that rest of the speed. A micro slip can't exceed that pre wrist opening 90% speed in any way I can fathom. I haven't said that it could. What I've said is that the spin to speed ratio can be different with a slip grip vs a rip appropriately late throw. Please check it for yourself from the original source to eliminate error sources like my memory if you're interested in the exact measurement results. If you're interested in better quality translation maybe you could ask man_utenbart who is Norwegian.

overall though, i don't even think about spin anymore. it is possible to have some manipulation of flight characteristics with spin changes well within your power range, but i find it much more consistent to manipulate flight characteristics with intentional OAT since it doesn't affect launch direction or force transfer.

what i would give warning to are the guys on here who are not huge snap throwers attempting to manipulate spin and trying to cite that as the reason for the flight changes. velocity, nose down, and the force plane are responsible for the majority of flight characteristics.

I agree and do the same as above with the exception of keeping the option of minimizing spin as a fight shaping option open and thinking of it. Especially when challenging myself to approach a familiar hole a different way than before.

 

[JR]

No offense taken I welcome critique because it may teach me something and save my behind. Careful with assumptions did you read the disclaimers of translating in the tread I read a nice thesis of long throws?

The one thing that stuck to my mind about the measurements and their statistical analysis was that there was only one statistically meaningful correlation found at 95 % confidence level in relation of flight distance and details of form. That was a positive correlation between lengthening elbow reach back distance away from the target. Untechnically speaking this means that you'll most likely throw farther when you reach back farther with the elbow.

I haven't been advocating not utilizing "angle, speed, oat etc". Manipulating spin is a minor effect whereas those mentioned by you and lake are issues of the highest importance and much more evident in flight. Just not all encompassing. And that is what I've been stressing -the plethora of options. The whole spectrum not just the visible or near visible parts. Each variable has an effect, especially visible in trick shots.

The master thesis JR is mentioning can be found here: http://www.tbgfrisbee.no/Tips/hovedoppgave.pdf
It's in norwegian though so even a Finn might have trouble reading it correctly (no offense JR ), technically more adept people than myself might be able to read something out of the tables and such I guess.

As far as I can understand, Carlsen finds most correlation between exit velocity of the disc and 1.rotational speed of the hips, 2.minimum elbow angle/max speed in elbow extension, and 3. disc rotation.
So, imporant things to practice would be footwork, elbow chop, disc pivot. I think Blake, Bradley et al should find much to like here

One of the ideas I found interesting, is how the subject with the highest disc speed holds on to his disc with both hands during reachback, Carlsen theorizes that this might help him in delaying shoulder rotation (his rotational speed peeks just after the hit while some of the others are de-accellerating at this point) and therefore be beneficial. i find it very plausible since coming through to early with your shoulders seems to be a commom problem - maybe grabbing your disc with both hands leads to a breakthrough in timing and after that it becomes an unneccessary crutch? I would suspect the habit of pointing your disc towards the target just before the x-step has a lot of the same function (adjusting rotational timing, but this might help someone with weight transfer timing as well).

Another interesting aspect is how Carlsen concludes that the best training would be leg and core muscles since he really can't show much effect from strong-arming at all. For instance, all subjects show almost no change in shoulder/upper arm angle, and even though elbow extension is one of the most important elements, this is thought to be mostly a result of prior movement (too quick to be conscious).

What strikes me when reading ths and other threads, Blake, is how you have an ability to look beyond the first explanation that comes to mind, and if there is no certain knowledge to look at all possible factors before forming an opinion as to what is the most plausible explanation. Since DG is dominated by teaching based on personal experience, it's just the kind of critical thinking that's needed.
Not to insult anyone else here, but I find the arguments for people actually manipulating spin - not angle, speed, oat etc - are not very convincing so far...

 

[Blake_T1]

One of the ideas I found interesting, is how the subject with the highest disc speed holds on to his disc with both hands during reachback, Carlsen theorizes that this might help him in delaying shoulder rotation (his rotational speed peeks just after the hit while some of the others are de-accellerating at this point) and therefore be beneficial. i find it very plausible since coming through to early with your shoulders seems to be a commom problem - maybe grabbing your disc with both hands leads to a breakthrough in timing and after that it becomes an unneccessary crutch? I would suspect the habit of pointing your disc towards the target just before the x-step has a lot of the same function (adjusting rotational timing, but this might help someone with weight transfer timing as well).

actually... holding the disc with both hands during reach back has a major negative bi-product unless it's a very loose hold with the offhand. 99% of players i come across who hold with both hands end up with perfectly squared shoulders. that is, the shoulders remain parallel to one another throughout the reach. however, if you watch at the rotation of most players, especially the many of euro guys who generally have a low reach and pull line (with a dropped right shoulder), the right shoulder ends up turned farther away from the target than the left shoulder. if the shoulders remain parallel the entire time, the amount of turn of both shoulders remains the same. while this works on flat/anhyzer shots, it is not very conducive to performing hyzer throws. Brad Hammock and Ken Climo are two of the only top pros i know of that have a delayed hold on the disc and are still predominantly hyzer throwers. Hammock is still able to shift the shoulder plane quite well and Climo lets go immediately before max reach back (and is able to manipulate the shoulder plane). if you watch a number of players who do hold with their off-hand, their shoulders tend to rotate on a flat plane no matter what angle the disc starts on/finishes on, with the result being OAT on any shot that isn't flat.

What strikes me when reading ths and other threads, Blake, is how you have an ability to look beyond the first explanation that comes to mind, and if there is no certain knowledge to look at all possible factors before forming an opinion as to what is the most plausible explanation. Since DG is dominated by teaching based on personal experience, it's just the kind of critical thinking that's needed.

i've worked with 600+ players in person and only come across about 10 that are coordinated enough to make minor changes to their throw in 5 or less tries (not all of them were high level pros). it's due to this fact that i doubt there are many out there who could consistently manipulate spin on throws while keeping every other factor the same (velocity, acceleration, force transfer, nose angle, OAT). the bulk of the lesson work i do (beyond putting) is taking guys from 350' and trying to get them to 450' or at least able to do everything possible at 350' (this everything possible is also for guys who get to 450'). much of the myths of troubleshooting technique problems

the general process is eliminating OAT and teaching people how to throw pure (most don't, but this knowledge is necessary for learning to hit the snot out of a disc). the next step is timing/release/extension... basically snap. when the fundamentals of snap are learned, that's when introducing OAT becomes a factor again. shot shaping requires the ability to start with the body and disc on one plane and then snapping the disc onto another plane (with subsequent body adjustments). there's a whole lot can be done with that and it can be done without any spin manipulation.

Another interesting aspect is how Carlsen concludes that the best training would be leg and core muscles since he really can't show much effect from strong-arming at all. For instance, all subjects show almost no change in shoulder/upper arm angle, and even though elbow extension is one of the most important elements, this is thought to be mostly a result of prior movement (too quick to be conscious).

building leg and core muscles will always help, but it's an odd one. for players with big snap performing throws under 450', leg power is responsible for less than 30% of distance, often times closer to 15%. imo, the key muscles in throwing are hand strength and the extensor muscles in the forearm, since those are the ones that dictate how much force can be transferred to the disc during wrist extension. now for someone who has reached peak snap power, building legs and core will help yield gradual incremental results... but these will likely happen in the realm of 1-3% contributions and build slowly over time.

increasing elbow extension can be done with body positions that increase the peak elbow bend, but yah, it's not something you work on building via conscious motion of the elbow.

 

[Moseley]

JR, sorry! I guess I tend to assume too much - wich is not very clever when I kind of accuse you of doing just that My bsic assumption is that we're all in here to figure things out.

The one thing that stuck to my mind about the measurements and their statistical analysis was that there was only one statistically meaningful correlation found at 95 % confidence level in relation of flight distance and details of form. That was a positive correlation between lengthening elbow reach back distance away from the target. Untechnically speaking this means that you'll most likely throw farther when you reach back farther with the elbow.

This is not quite correct but seems to be a commom misconception of his findings; the correlation is between hip/shoulder movement and disc exit speed - Carlsen says (freely translated from a norwegian DG forum): "one should rotate both pelvis and upper body farther away from the direction of the throw". This will happen naturally with a long reach back, but he later comments on bent elbow technique as being in no conflict with his own studies.

imo, the key muscles in throwing are hand strength and the extensor muscles in the forearm, since those are the ones that dictate how much force can be transferred to the disc during wrist extension.

Carlsen notes that the recording frequency is (probably) too low to capture the necessary nuances in wrist/hand movement, I think that's why he does not discuss these factors much. He notes that positioning the frisbee during the throw is extremely important though...
Someone should do a follow up, focusing more on wrist movement, vertical movement, disc angles, grip differences - but my hopes are not up...

Climo lets go immediately before max reach back

the subject with the highest disc speed just might be a fan of Climo (judging from his norwegian forum posts at least), no surprise he lets go before max reach back and afaik he's hyzer dominant as well

 

[JHern]

40% rotational decrease is still within the 8-15 RPS bounds i laid out earlier, which don't yield significant flight changes.

You guys are the experts on disc throwing (I'm relatively just an amateur), but Blake, this raises my hackles a bit as a physicist. 8-15 Hz is a variation by a factor of two. The torques acting on a disc in flight will only depend on the flight speed and orientation (i.e., nose/hyzer angle). (I think wind tunnel tests have put to rest any notion that rotation affects the torques.) A disc flying with 15 Hz spin will turn (or fade) about twice as slowly as a disc flying with 8 Hz spin given the same flight speed and orientation.

This is not conjecture, it is a law of physics.

Now, maybe this won't affect distance as much as speed alone, but it would surely affect the lateral (sideways) motion of a disc on any number of lines (slower rotation=>more turn AND more fade, everything else equal), as much or perhaps more than adding OAT.

 

[Blake_T1]

You guys are the experts on disc throwing (I'm relatively just an amateur), but Blake, this raises my hackles a bit as a physicist. 8-15 Hz is a variation by a factor of two. The torques acting on a disc in flight will only depend on the flight speed and orientation (i.e., nose/hyzer angle). (I think wind tunnel tests have put to rest any notion that rotation affects the torques.) A disc flying with 15 Hz spin will turn (or fade) about twice as slowly as a disc flying with 8 Hz spin given the same flight speed and orientation.

This is not conjecture, it is a law of physics.

i'm very interested in the physics equations if you have them handy. i was an engineering major for 2 years and a physics major for 2 years but i'm so far removed from it that i only remember a handful of equations.

keep in mind that the 8-15 RPS is a range that encompasses at least 2/3rds of players, possibly more. someone's ability to manipulate spin while keeping launch angles, launch velocity, etc. the same is likely more along the lines of 2-5 RPS. it's the "being able to keep everything else the same while still manipulating spin" part of things that i don't put a lot of stock in.

this is also very dependent upon speed ranges and the disc's aerodynamic properties. if you ever wonder why pro bags are often so similar in terms of their workhorse discs (and the weights), there's only a handful of discs on the market that seem to whittle their way into nearly every pro bag. these discs are usually those that are extremely HSS.

for a player who has an average launch velocity near 70mph (these guys also generally have tremendous amounts of spin), why is it that nearly every disc flips unless it's an extremely stable model and at max weight? how much spin would it take to make a disc like a sidewinder not turn over with a 70mph launch velocity and 5 degrees of nose down?

 

[Blake_T1]

something else i was going to mention but forgot.

when you take a disc like a boss, imo, being able to throw > 55mph is more important than how many RPS you can put on it. if you were to throw it 35 mph you'd need an ungodly amount of spin on it to get it to hold stable for very long at all.

on a similar note it would be interesting to see the relationships between both rim width to spin and diameter to spin.

 

[JHern]

You guys are the experts on disc throwing (I'm relatively just an amateur), but Blake, this raises my hackles a bit as a physicist. 8-15 Hz is a variation by a factor of two. The torques acting on a disc in flight will only depend on the flight speed and orientation (i.e., nose/hyzer angle). (I think wind tunnel tests have put to rest any notion that rotation affects the torques.) A disc flying with 15 Hz spin will turn (or fade) about twice as slowly as a disc flying with 8 Hz spin given the same flight speed and orientation.

This is not conjecture, it is a law of physics.

i'm very interested in the physics equations if you have them handy. i was an engineering major for 2 years and a physics major for 2 years but i'm so far removed from it that i only remember a handful of equations.

keep in mind that the 8-15 RPS is a range that encompasses at least 2/3rds of players, possibly more. someone's ability to manipulate spin while keeping launch angles, launch velocity, etc. the same is likely more along the lines of 2-5 RPS. it's the "being able to keep everything else the same while still manipulating spin" part of things that i don't put a lot of stock in.

this is also very dependent upon speed ranges and the disc's aerodynamic properties. if you ever wonder why pro bags are often so similar in terms of their workhorse discs (and the weights), there's only a handful of discs on the market that seem to whittle their way into nearly every pro bag. these discs are usually those that are extremely HSS.

for a player who has an average launch velocity near 70mph (these guys also generally have tremendous amounts of spin), why is it that nearly every disc flips unless it's an extremely stable model and at max weight? how much spin would it take to make a disc like a sidewinder not turn over with a 70mph launch velocity and 5 degrees of nose down?

The basic law is:

dL/dt=I*(dw/dt)=tau

where L is angular momentum, t is time, I is the moment of inertia (about the spin axis), w is the angular velocity and tau is the torque (or moment of force) acting on the disc. d/dt is the time derivative (rate of change with time).

This is a vector equation (and strictly speaking, I is a second rank tensor), so even if the rotation rate is constant, disc turn/fade amounts to a change in orientation of the angular velocity vector and hence non-zero terms in the vector equation. The magnitude of I increases as the disc mass, disc radius, and amount of disc material distributed outward toward the rim increases (it is easy to calculate). Aerodynamic forces (due to linear velocity, orientation, and disc shape) govern tau. For a disc turning in flight, tau is perpendicular to w, and causes the disc to precess even though the rotation rate doesn't change appreciably. According to the basic equation, the rate of turning is tau/I. This is why heavier discs turn over less than lighter discs for the same throw velocity/orientation/disc mold.

The answer to your question about the Sidewinder is: For a very HSS disc, tau might be nearly zero at a given high velocity and orientation (such as 70 MPH, 5 degrees nose down) owing to aerodynamic factors alone, while for a Sidewinder the aerodynamic factors might be such that tau is not zero for the same aerodynamic factors (i.e., speed, orientation). In this case the Sidewinder will turn no matter how rapidly it spins. The relative rate at which it turns will be inversely proportional to the spin rate,

dlogw/dt=tau/(I*w)

Say tau_sw is the torque on a Sidewinder (with moment of inertia I_sw) at 70 MPH and 5 degrees nose down, while tau_od is the torque on "other disc" (with moment of inertia I_od) at 70 MPH and 5 degrees nose down. The relative rate of turn on the Sidewinder is given by dividing the equation for one by the other,

dw_sw/dt=dw_od/dt*(tau_sw/tau_od)*(I_od/I_sw)

Calculating tau for various speeds and orientations is difficult (it involves solving the turbulent flow problem), and would require a super-computer simulation to do it properly. In a sense, what you do is a natural simulation by just going out and throwing consistently at various speeds/nose angles and judging LSS and HSS. A computer simulation can tell you the same things, but at much greater expense. Of course, your number system is somewhat subjective and works in a relative sense, while the full computer simulation would yield more objective data. It would also give a value for tau at all disc speeds, instead of just two speeds (it would be interesting to see the turning torque plotted as a function of speed for various nose angles...it is probably not linear, and could be curved this way or that way for different molds). This isn't, of course, meant to take anything away from the valuable services you provide...it is the best thing around right now.

 

[JHern]

something else i was going to mention but forgot.

when you take a disc like a boss, imo, being able to throw > 55mph is more important than how many RPS you can put on it. if you were to throw it 35 mph you'd need an ungodly amount of spin on it to get it to hold stable for very long at all.

on a similar note it would be interesting to see the relationships between both rim width to spin and diameter to spin.

Here's a fun brain teaser...if the Boss had no spin, then it wouldn't turn/fade at all!

 

[Blake_T1]

thanks for the nerd-work.

there was a long time when i was looking at it more from mathematical standpoints that i felt spin had a lot more to do with things than i believe now. the jist of what i'm picking up is that it's very model dependent and comes into play within specific speed ranges for each disc.

i think it was mainly due to realizing the impact of OAT on people's throws as well as the near impossibility of consistently manipulating spin while retaining "the other mechanics" of the throw.

another thing i've thought about recently is how flight behaviors change with the contrasting styles (swedish vs. american) in terms of throwing (what will be) the nose of the disc vs. throwing the center of the disc in how the release is focused.

yet another thing i used to think about is the deceleration of spin rates over the course of flight and if players that harness more angular velocity on the launch have the same rate of spin deceleration as players who do not clear the wrist as much (even if their initial launch spin was the same).

overall though, for 99.9% of players, i believe spin is the last thing they should worry about.

the greatest overall effect i have seen from spin is how discs riccochet and skip. for those who generate "hyperspin" (less than 1/3rd of those who can throw 450' do), there is a much more noticeable stable "lock-in" for stable discs than players who cannot. when i used to drive far (2002) i had plenty of 440'+ throws that had 0 turn and 0 fade with broken in dx teebirds but my spin rate was absurd back then.

 

[Bradley Walker]

If you watch the video I made in the Snap 2009 thread, I was cut off right before I came to the discussion of MOI (moment of inertia). There is a moment of inertia around the center of the disc but there is also one around the hand itself.

At the disc pivot, which is THE substantial focus of disc power for nearly everyone of normal ability, the heavier the rim, the more difficult the disc becomes to pivot around the wrist. As the weight in the disc becomes more concentrated in the rim, the weight is increased from the pivot point of the lock fingers at a longer moment (the other side of the disc).

In other words, wide rim discs are much harder to snap, because the MOI of the disc around the lock point is so much greater.

From my tests, the wider the rim, the lower the initial velocity. In other words, a Wizard goes 65 MPH, a Teebird, 60 MPH, and a Boss 55 MPH OUT OF THE HAND. I, at first, believed this was all grip related, but I now believe that the wide rim discs simply have a much much greater weight "in the head of the hammer" that must be swung around the arc of the disc pivot.

It is much more difficult to accelerate a golf club of swingweight e8 than it is a c9... it is the same principle. The more plastic concentrated in the rim, the heaver the head of the hammer.

 

[masterbeato]

my throw derives from focusing on leveraging the disc from the rim but i try to leverage the disc from the center rather than the rim because i have been focusing more on the Sweden style lately because i am curious about it. but i have no idea how to go about trying to focus on the center.

the center is different from what you are describing about rim focus, and being changed due to the width of the rim. since leveraging from the rim is changed due to rim width, does it also change when trying to leverage it from the center? or do i just not understand?

the reason why i am asking is because i want to learn more about it and i am asking how to go about doing this?

or maybe everything in the hit is leveraged from the rim regardless of the style but i know for a fact that the Sweden technique is leveraged with far more power.

 

[JR]

No worries at you noticed the danger in assuming Live and learn.

I don't recall exactly how Öystein described things but my recollection is that a table with correlations had only one statistically meaningful link and that was the elbow reach back distance. Which comes from reaching back with the arm plus what you mentioned about the hips and shoulders turning back. They all result in the elbow being farther back. I see no conflict here.

We have a physicist here and I've got 300 FPS obliquely above footage of Avery Jenkins back handing and doing 360s plus nearly vertically down forehands. Maybe you could do an analysis on that to see what you can see. It's on youtube just search with his name and two view points or I could put up the top down data on some file sharing site for easier frame by frame moving for more accurate measuring.

Jag antar att du förstår Norska eller något liknande språk eller hur?

JR, sorry! I guess I tend to assume too much - wich is not very clever when I kind of accuse you of doing just that My bsic assumption is that we're all in here to figure things out.

The one thing that stuck to my mind about the measurements and their statistical analysis was that there was only one statistically meaningful correlation found at 95 % confidence level in relation of flight distance and details of form. That was a positive correlation between lengthening elbow reach back distance away from the target. Untechnically speaking this means that you'll most likely throw farther when you reach back farther with the elbow.

This is not quite correct but seems to be a commom misconception of his findings; the correlation is between hip/shoulder movement and disc exit speed - Carlsen says (freely translated from a norwegian DG forum): "one should rotate both pelvis and upper body farther away from the direction of the throw". This will happen naturally with a long reach back, but he later comments on bent elbow technique as being in no conflict with his own studies.

 

[JR]

Masterbeato I have some slow motion footage of European styles showing wrist action well. Wait and see for yourself. One of the most important Swedes Tomas Ekström has a very DGR appproved form. Whereas Linus Åström uses the left arm with a distinctively Swedish style. Can't promise about Johannes Högberg because I have to see if there's worthy footage available.

JHern there are so many disc configurations for putters, mids and drivers and so many different variable sets among those discs that it's difficult to generalize what kinds of practical effects one would get with each detail modification because ceteris paribus rarely exists between molds when even different plastics tend to change weight distribution etc. on discs of the same mold. That's why it's difficult to pin down a single definition for spin rate change susceptibility in air for disc classes. And how the flight could be manipulated with spin rate change _alone_. When it's more likely hole in your disc selection or the inability to manipulate the flight with intentional OAT, power generation change or puring the shot. However; some discs are clearly responding to a lack of spin more than others. More often than not overstable discs that you can throw at over cruising speed and understable discs you can just make fly straight with your best effort become more stable on bad throws with a slip/poorly timed or powered pinch and the resulting loss in spin rate.

I'm not sure there's much more practical advice for regular throwing than fulfilling flight differences in bag setup and using discs you can throw to every possible way and learning to throw purely and getting enough muscle power to hold on to the disc long enough. Could you please redo muscle power calculations that mafa did in a hurry about the needed pinch power of a 45 MPH throw with the index finger and thumb at pro style rip point of 2.30 on the disc edge to see if you're in the same ballpark with 175 gram disc. If mafa made no mistakes the discs clearly rip and not even a gorilla can hold on at those forces tearing the disc away from the thumb lock. Which means that there's a benefit of having the finger pinch strength of an Olympic athlete.

Anybody else have practical goals to work toward in training and throwing and disc design relative to spinning the disc in different speed to spin ratios? Too tired now going to sleep so my head ain't probably putting out everything relevant now.

 

[JHern]

If you watch the video I made in the Snap 2009 thread, I was cut off right before I came to the discussion of MOI (moment of inertia). There is a moment of inertia around the center of the disc but there is also one around the hand itself.

Aha! So this is what you were getting around to saying...BTW, great video. When are you going to post a better quality version? We're going to keep nagging until you do.

At the disc pivot, which is THE substantial focus of disc power for nearly everyone of normal ability, the heavier the rim, the more difficult the disc becomes to pivot around the wrist. As the weight in the disc becomes more concentrated in the rim, the weight is increased from the pivot point of the lock fingers at a longer moment (the other side of the disc)...In other words, wide rim discs are much harder to snap, because the MOI of the disc around the lock point is so much greater...From my tests, the wider the rim, the lower the initial velocity. In other words, a Wizard goes 65 MPH, a Teebird, 60 MPH, and a Boss 55 MPH OUT OF THE HAND. I, at first, believed this was all grip related, but I now believe that the wide rim discs simply have a much much greater weight "in the head of the hammer" that must be swung around the arc of the disc pivot...

Yes, this sounds correct. Note, however, that for the same reasons the Boss need not spin as fast to have the same angular momentum as a more rapidly spinning Wizard. In terms of inertial stability against turning and fading, this is the quantity that really counts.

 

[JHern]

JHern there are so many disc configurations for putters, mids and drivers and so many different variable sets among those discs that it's difficult to generalize what kinds of practical effects one would get with each detail modification because ceteris paribus rarely exists between molds when even different plastics tend to change weight distribution etc. on discs of the same mold.....

Yes, of course variety in molds is important, but so is the physics. Consider a big S-turn throw, like a Valkyrie aired out for max D. The more spin you have, the slower the turn of the disc in flight (and the slower the fade at the end), and hence the S becomes tighter. A slower spin rate enhances the turn (and the fade), so that the curvature of the flight path becomes larger and more accentuated. In other words, more spin=less left->right->left motion. Of course, if you have weaker spin, you could just pick up a more stable mold and get a tighter S. And that would take care of that!

 

[JR]

JHern there are so many disc configurations for putters, mids and drivers and so many different variable sets among those discs that it's difficult to generalize what kinds of practical effects one would get with each detail modification because ceteris paribus rarely exists between molds when even different plastics tend to change weight distribution etc. on discs of the same mold.....

Yes, of course variety in molds is important, but so is the physics. Consider a big S-turn throw, like a Valkyrie aired out for max D. The more spin you have, the slower the turn of the disc in flight (and the slower the fade at the end), and hence the S becomes tighter. A slower spin rate enhances the turn (and the fade), so that the curvature of the flight path becomes larger and more accentuated. In other words, more spin=less left->right->left motion. Of course, if you have weaker spin, you could just pick up a more stable mold and get a tighter S. And that would take care of that!

Completely agree but that was not my main motivation to write. I was getting at more often applicable real world differences which are brought about by enhancing grip strength and getting a cleaner rip which increases spin rate anyway and you're not gonna throw 400' easily or without wind assistance with a loose/micro slipping grip. Those improvements are something you can train and achieve IRL and are applicable in any throw.

A cleaner grip and possibly somewhat better gripping power is what eliminated left right play fro my 400' line drive with a new DX 175 Valkyrie so the added spin and later rip point and very likely less finger chafing/sticking induced OAT certainly are plausible explanations to the straightened flight. If I had to guess each played a part.

For a max D S-curve a person that was used to a micro slip and suddenly got a good grip and rip at a proper late time with added disc pivot would most likely get a short anhyzer to the ground with a Valkyrie. When throwing the same otherwise because that disc isn't great at flexing back from anhyzer which makes it ideal for that flight line. In this scenario the added spin forces a lessening of anhyzer angle or addition of height thus making a clear impact in distance and the sideways action of the flight at different points. Therefore it's a combination of adjusting your aim, power, grip strength, keeping the throw clean or intentionally messing with it and the election of the correct disc for the job. You need to adjust everything else when one variable changes and that's for me the most important practical function of messing with spin to speed ratio.

One needs to know the changes of spin to speed ratio has in flight just like one wants to be able to manipulate the flight with intentional OAT to increase the amount of available tricks. The benefit being getting closer to the pin and out of any kind of trouble.