E-I Profile and how it might predict "feel" & performance (NOT stiffness)

[Howard_Jones]

I really dont know what equipment the factories use for this, neither what Russ Ryden uses, and most club makers only have a standard CPM reader, and many dont even have the 4 inch pyramid clamp needed as the shaft goes down in diameter. I stopped measuring shafts with the pyramid clam after i broke a few expensive shafts to get a reading with 11 inch as beam, so shaft measurements like this is anything but easy and 2 users hardly ever get the same numbers....

Im not sure, but maybe we can "improve" the graphs if we used a conversion factor vs Beam, but it will take TONs of testing to find that factor. My thinking is using SW points as difference like this.

EXAMPLE - BEAM 41 vs 40 (if we measure inch by inch) has a difference of 6 SWP or 6 CPM, so we have to subtract 6 CPM pr inch or 30 CPM pr measure point if we used 5 inch Beam difference.

The RIP ALPHA numbers from Tom Wishon "converted" would then look like this: but it want be correct, since 6 SWP is NOT a constant but average, but we CANT stretch that "rule of thumb" all the way, the tip still looks stiffer than butt..( ive used a correction factor of 30 CPM DOWN for each 5 inch shorter Beam, and still, tip side looks more than 3x stiffer than butt...

So...this is NOT easy....

But if you won the lottery, Golfmechanix has the machine...price on request onlyhttp://www.golfmechanix.com/Items.asp?Pdts=05

I guess its this one shown in this video, it looks "expensive"....https://www.youtube.com/watch?v=mL9SAgj1p4w

[Golfrnut]

 

It looks like he may still use the one that's pictured here? Fit2Score EI Instrument

Would explain why his deflections don't really mirror that of something like what you would see using a deflection board or a more linear line like what you see in Tom's software.

[Z1ggy16]

Yeah a factor like that is probably variable, depending on position and maybe also even the shaft itself. Not going to be easy to estimate...

 

Yeah loll that machine looks like $30k+, probably only bought my large golf companies to test their own product, or competitor product. Would be nice to have if I got rich.

I guess for now I have to assume that Russ tested all these wood shafts on the same or similar machine, using the same methods, with no scaling. I mean... if he is introducing such variables like scaling the graphs so they all fit in the same area, it's almost useless data? At least when I see my graphs and compare them to what's on OEM websites (MCA and Fuji now post EI curves) it looks pretty similar. Maybe the exact values aren't 1:1, but shapes and relative position on the Y axis is comparable still (I hope).

I may for the heck of it, look into buying a couple used shafts from that chart with softer mid areas... Seeing the Smoke with the highest mid values makes me think it's not the best for me. Launch with this shaft is pretty low... Even with my driver turned up from 9 to 11* (and I have decent speed).

[Z1ggy16]

But is Tom actually plotting a full curve? To me looks like he takes measurements every 5 inches, draws a scatter, then has excel or whatever program he uses draw a best fit line.

[Howard_Jones]

That one is "only" 2500 USD, but thats not "the real deal", there is a zero missing....and even the one to 2500 will be hard to pay back since most players is not really interested in datas like this.

Next issue is that we need at least 3 shafts of the same model and flex to get a idea of average and tolerances, so shaft measuring is anything but easy (or cheap), and many players dont even understand the importance of a CPM control, the saying is that its Hog wash, even if the shaft at hand might be a full flex off vs its label compared to its brothers in the same model and flex label.....

This shafts was a test done for the readers here at WRX, random shafts and models, 2- 6 of each, but non of them is identical, so shaft compare is a branch of its own.

All shafts is tested at full length, and measure Label up/down and at weak and strong FLO lines. Some shafts is anything but symmetric, others "off flex"with quite a lot, and in this case we have ONLY compared 1 point on each model...how would that look like on a full EI profile'? correct, we cant even be sure it will have the same profile, so i tested shafts in 5 inch steps down to 16, but dropped shorter beam of risk for breakage with the equipment ive got. (Digiflex)

[Golfrnut]

 

Hmm. That's a great question. HaHa! I've never actually put the numbers on a graph to see how they plot. Has anyone?

 

As for Russ's gauge. I can only shoulder-shrug. It's the one he's advertising as the "latest and greatest".

[Z1ggy16]

Interesting. Most articles I've read by Russ, he's always saying how radial geometry these says is excellent, with something like 98%+ radial consistency with very small std dev, meaning the shaft should be deflecting pretty similarly, regardless of how it's oriented (label up, down, etc. no need for SST puring).

Gosh I really hope his numbers aren't skewed. I just spent a bunch of time on that graph plus I calculated the areas under each curve, which should be a good "dimensionless" figure for relative stiffness. I even broke it out into tip mid butt and overall. Sigh.

[Z1ggy16]

For Tom's numbers no but just based on what I see, it's pretty much what I described: 5-6 points on a scatter plot, then a best fit is drawn by the program, probably an exp best fit so it looks smooth. Can't be sure though, never did the work.

 

Yeah after seeing the machine from golfmech. there's no way Russ' tool is latest and greatest. That thing is 100% automated, only human interaction is putting the shaft into the jig and probably torquing it down.

[Howard_Jones]

Tom uses a 4 inch pyramid clamp, and a 454 gram tip weight, and then 5 inch between measure points, so for woods Beam 41 is the longest, (beam 41 plus clamp 4 = 45 long "net cut" shaft), next is 36 beam or 40 long net cut shaft...simple system that does a decent job. When we compare 2 shafts in that system, we shall look at the same beam length, and judge the differences as %, NOT as CPMs. so a difference butt side of 7 CPM is a full flex (equal to 10 CPM with a 5.0" clamp), while the same 7 CPM as difference on Beam 11 is "next to nothing" or about the tolerances we see from shaft to shaft. Its far from perfect, but the best so far since so many shaft was measured and possible to compare. I hope he will finish the update needed for a new version.

[Z1ggy16]

Same, I hope he finishes and puts more new models in there. So.. in your opinion, my endeavor with comparing profiles/shapes of curves from Russ is mostly pointless? I was hoping to use this as a guide to "blind fit" me into a new driver shaft since the Smoke shaft has been up and down for me. Perhaps I will just wait til spring and get another fitting...Problem is, even as good as True Spec is...they don't have everything. I'm the type I literally want to try everything not just 3 or 4...And I do find results can vary from indoor swing to real golf swing.

[Howard_Jones]

LOL, you should have seen all the Rabbit holes ive been down into, trying to understand both different measure systems and shafts, and if its any comfort, you already know and understand way more of this than most of them who owns a CPM reader. We still see people who measure with grips on (4-30 CPM lower return value depending on grip model, size and tape), we see those who claims their shafts measure silly stiff...because they used a 5.0" clamp and compared the numbers to a RIFLE FCM chart where a 2.5" inch clamp is used (differences is 17 to 25 CPM depending on shaft model, so a shaft expected to be 6.0 comes out as 7.7 to 8.5), and we see those stupid enough to tip trim a wood shaft to please a chart on the wall who was never made for judgement of that shaft...they end up destroying that shaft who could be a 400 USD wood shaft....

So whats a few hours behind the PC compared to the disappointment many gets when they try their "flex matched 400 USD shaft" the first time? you learned something, and knowledge aint without value, you want fail on this things and pay hard cash for not doing your homework like many others have.

I remember the first set of DG X100 i made and measured....i had head ace for days, WTF did i do wrong since that set had a progressive slope as FCM? The #3 iron was like FCM 6.4 and the PW FCM 7.2 but we all know that DG X100 is suppose to be FCM 6.8 right?.....well the thing is, DG has a steeper flex slope than RIFLE FCM by design, i did nothing wrong, i just did not know any better that fist time i measured a set DG X100 build to the tightest tolerances possible, but still it looked like i made a huge mistake when i saw the numbers....Rome was not built in one day, and understanding shafts, how to measure and judge them is the same, it takes lots of time.

 

[Howard_Jones]

Dont rush it, its winter most places now, and nobody is able to try off all possible options there is, so this "systems" no matter what it is, is helpful to eliminate and reduce the numbers of options.

I cant recall all numbers now, but in my shop i had more than 5000 possible combinations of heads and shafts for drivers alone, and wedges who was my specialty, more than 10.000 combos, BEFORE we added personal hand grinding into is, so its not possible to try them all, and i ONLY had True Temper, Rifle, Project X and Grafalloy, but the full line up of after marked and Tour issue models, but when you X them up with 12-15 different head and loft combos, we ends up with a number nobody is able try try off, so we need to eliminate most of them one way or another without testing.

[DaveMac]

@Z1ggy16
Kudos for your efforts in correlating the EI data from pretty much the only cost effective source available to us at the minute. It is nice to see something interesting on this forum for a change.
Getting back to your question >So... what really is responsible for feel and what we perceive to like?
The reality is even with the full EI, Torque, Hoop strength and deflection data, two shafts with the same ‘strength’ / profile, will still have distinct personalities. Materials, wall thickness and shaft diameter, can and are used to influence a shaft’s bending properties.
Looking at the golfer side of the question, there are obviously golfer’s pretty much in three camps, those that can feel the differences, those that can feel the difference’s but can’t or don’t feel qualified communicate their experience and finally those who don’t feel any difference. The other issue from the golfer’s side of the question, is we tend to only consider shaft matching in the ball to target plane, when the reality is the highest stress on a shaft can often be the result of a swing compensation move.
This is a topic that has been of great interest to me, naively, I thought shaft matching is a problem that could be solved by technology but the more I have studied the issue, the more disillusioned I have become.

[Z1ggy16]

Wow that's quite a lot of combo haha. I guess this was all kick started via my fitting on Dec27 for my wedges, when it was so crystal clear to the fitter and myself, the modus shaft and S400 were levels better for me than the KBS we also tried. After being fit into modus with irons 2 different times... I figure hey this is not a coincidence, then maybe I should extrapolate this and start looking at hybrid and also woods. Of course, so many variables I will go cray. I don't think it's a single answer and try and fail is part of the process. I think I am most bothered by the fact all those curves look different, yet I enjoyed using or testing them all. So then it makes me think, maybe profile matters very little? but then if it doesn't there's no way to eliminate a shaft until you try.

Appreciate the nice words. I think with a lotttt of money and time, these questions could be answered, but the demand for this knowledge really isn't there. Custom fitting is really just become a mainstay of the golfing world and I think the way it's done now is probably just the beginning. I eventually see the veryyy distance future being something where at least on the professional level, OEMs can use AI and other advanced software to literally build a player the "perfect shaft" profile based on his swing inputs. It would be 100% custom to him and it would be tuned to perform just right for him/her.

I'm kind of attacking this from the reverse angle, trying to pick a profile based on how I feel and what I feel... but as it's been said above, there's many variables not expressed in charts like materials and whatnot.

[Jim53]

Excellent thread, I honestly don't understand a lot of what is being offered and in another thread about shafts I asked the same question as the OP only in reverse. I love my GD Ad BB 7x in my Driver and wanted to find a similar feeling shaft for my irons. Unfortunately there were no replies, perhaps it was just poorly placed question.

Finding this thread has now convinced me what I am asking for is not anything that can be predicted at this time and more shaft testing is the only true answer.

[Z1ggy16]

Yeah it's sort of... annoying, that we can't just be like well I fit into A, B and C profiles.. a computer should be able to spit out D, E and F profiles that I'd do almost definitely fit into. Reality is it just isn't as simple as a few inputs... there are so many.

[Golfrnut]

 

Going to be hard to make that leap directly. You may be able to make some very broad generalizations to start base on stiffness per a rated flex (I.E maybe liking shafts with a softer handle or tip section for their rated flex, etc) but agree, trail and error is going to be the majority of the way to get there.

[A.Princey]

This just adds more fuel to the already blazing fire of shaft datametrics, but couldn't one do a deflection with a heavier weight, but keep that weight exactly the same distance from the measure point to eliminate torque increase at distance? Maybe I'm completely misunderstanding how the bend profiles are generated.

For example, start a measurement at the butt with the weight 5" closer to the tip, and make another measurement 1" closer to the tip, ever maintaining the 5" weight offset from the data point intact. Rinse and repeat.

[Howard_Jones]

Tom Wishons shaft profile software had a sorting function who made it possible to sort shafts from a reference shaft, and the others within a certain % factor "off" from the reference shaft, and if i recall right, back then (more than 5 years ago), we ended up with about 7 different profiles only so they could have been labeled A, B, C, D, E, F, G, and H, where the actual difference was stronger or weaker within the same profile. Today we have a few more profiles than those 7, but it seems like its possible to group them like this, IF we had access to EI numbers or something close to that who was reliable numbers. A project like this is bigger than any of us can raise and put to life, and thats why i look forward to the day Tom Wishon re-launch his software in the new version.

The issue will always be access to new shaft models, i know Tom had that issue, not all shaft manufacturers was happy for what he did, so they stopped sending him shafts, but i had a few ideas of how that could be solved, but i have not talked to Tom about it. My idea was simply that if there was models missing, there would always be a player who was willing to lend out his shaft, and in return have that shafts true specs. We dont really need "raw uncut" shafts to make it, since nobody plays shafts at its full length, and the most interesting datas is "play ready shafts" at "standard", shorter or over length, and if possible both as hard stepped or soft stepped to see how each shaft model/profile changes, because they dont change equally when we do that.

This tread has been a good "brain storming" anyway, so maybe it will end up with something?

[Stuart_G]

Deflection and natural frequency are both directly related to the EI of the shaft and the golf shaft review graphs are based on deflection. And yes, there is more than one way to measure deflection (just like there are multiple ways to measure frequency). So yes that would be another possible way to document the shaft stiffness profile. But it would really need to be a differential deflection due to the possibility of any residual bend in the shaft. e.g measure the deflection with a light weight A, then measure with a heavier weight B and record the difference. An alternative would be to take several measurements as you rotate the shaft and then use an average.

And if you want to convert that to EI - Cantilever Beams - Moments and Deflections

And FYI, differential deflection is another way to check and find a shaft spine and NBP and the amount of asymmetry in a shaft.

 

[Z1ggy16]

So I was about to expand my graph to add Pro OJ and I finally saw some units on the curves. Any clues as to the units you think?

Assumption is it's Newton-millimeters but it could be a different one depending on magnitude of the forces in play here. Still.... if I could find just 1 other wood graph showing units on the side, we could see if the graphs are scaled or not.

 

Edit: N/m. I just went to his other CK Pro graphs and they definitely aren't the same. He's doing something wacky and I'm very annoyed now. The heck is the point of releasing data if the reference points on the graph are all different??? Tom needs to get his software up and running again. I'd donate to the cause, that's for sure.

[Z1ggy16]

Bought a new Tour Z Xtreme for $115 online a minute ago...Going to see if what I feel matches up with the curve relative to the Smoke. I'll even get to game it next weekend when I'm playing.

[AvenueWay]

On 1/4/2020 at 12:00 AM, Valtiel said:

Oh absolutely, nothing I would share involves any actual EI profiles or images of them, merely a table of steel shaft names with a list of graphite shafts that have similar bend profile characteristics.

Anything ever come of this? I’d definitely be interested in seeing what you found 

[Valtiel]

2 hours ago, AvenueWay said:

Anything ever come of this? I’d definitely be interested in seeing what you found 

Hey thanks for reminding me, it is one of those little projects that is sitting unfinished right now. I haven't been able to justify the time to finish it up with work/life right now, but I do hope to get it done at some point. 

[Tdsjfb]

I'd be interested to see an EI comparison of the Tour 65 and Alta 55CB (in Stiff).

[TJ83]

Just read the entire thread, it was a great read! I like the idea of a master list as a rough starting point for finding something that might work with your swing. We have no fitters here (would have to get on a plane and head stateside) so I'd definitely donate or pay for a list. I've been using this forum over the years to gather information about equipment, more specifically shafts, then after reading a ton make an "educated" guess haha. Thankfully I haven't had a disaster yet......🤞🏽

[cw1209]

Couple things to add here. Tom Wishon, Russ Ryden and S3 are all measuring their shafts with different tools and the very reason why their bend profiles all look different. 

 

1) Tom Wishon is measuring frequency at multiple positions on the shaft. "Frequency" in the traditional sense was a single measurement at the butt end. Tom used frequency measurements at multiples positions on the shaft as a tool for comparison. Frequency: "Where the shaft is clamped at the butt end, and the shaft is pulled and released with a weight on the tip end. This causes the shaft to oscillate back and forth. Generally, the faster it oscillates, the stiffer the shaft. Shaft mass can also slightly affect this measurement. If two shafts have the same static flex, but one is significantly heavier, the heavier shaft will have a slightly lower frequency measurement than the lighter one. Changes in frequency have a similar effect as static flex on performance."

 

2) Russ Ryden is evaluated shafts using hydraulic press to measure deflection. I would be careful comparing the graphs you can find in the $10/year subscription. These graphs are the composite of all weights and flexes measured for a given shaft. The composite bend profile may not look exactly like the bend profile of the 65 gram stiff flex shaft you are about to purchase. Bend profiles can evolve over weight classes and in some rare cases can be totally different. Russ does sell subscriptions to his Fit2Score software that does provide comparison of individual shafts, but costs $600 per year. http://fit2score.com/EI_Software.html. I kind of wonder if Russ caught on that people here were simply overlaying the bend profiles graphs in photoshop. His new charting system looks totally different.

 

3) Another option available to the retail consumer is S3 shaft fitting software. S3 uses a proprietary Shaft Simulation System (S3), which is a fully-automated shaft profiling machine. While more in line with the cost of Russ's Fit2Score software, it provides every level of detail a golfer could want to know about a shaft. Bend profiles of specific shafts are easily compared in their shaft database. Invaluable resource for the fitter or player that wants the most accurate shaft information. 

 

As with all things, you get what you pay for. 

[Z1ggy16]

How much to get the access to S3? 

[Poolparty]

60 per month

[AvenueWay]

On 3/1/2021 at 9:07 AM, cw1209 said:

Couple things to add here. Tom Wishon, Russ Ryden and S3 are all measuring their shafts with different tools and the very reason why their bend profiles all look different. 

 

1) Tom Wishon is measuring frequency at multiple positions on the shaft. "Frequency" in the traditional sense was a single measurement at the butt end. Tom used frequency measurements at multiples positions on the shaft as a tool for comparison. Frequency: "Where the shaft is clamped at the butt end, and the shaft is pulled and released with a weight on the tip end. This causes the shaft to oscillate back and forth. Generally, the faster it oscillates, the stiffer the shaft. Shaft mass can also slightly affect this measurement. If two shafts have the same static flex, but one is significantly heavier, the heavier shaft will have a slightly lower frequency measurement than the lighter one. Changes in frequency have a similar effect as static flex on performance."

 

2) Russ Ryden is evaluated shafts using hydraulic press to measure deflection. I would be careful comparing the graphs you can find in the $10/year subscription. These graphs are the composite of all weights and flexes measured for a given shaft. The composite bend profile may not look exactly like the bend profile of the 65 gram stiff flex shaft you are about to purchase. Bend profiles can evolve over weight classes and in some rare cases can be totally different. Russ does sell subscriptions to his Fit2Score software that does provide comparison of individual shafts, but costs $600 per year. http://fit2score.com/EI_Software.html. I kind of wonder if Russ caught on that people here were simply overlaying the bend profiles graphs in photoshop. His new charting system looks totally different.

 

3) Another option available to the retail consumer is S3 shaft fitting software. S3 uses a proprietary Shaft Simulation System (S3), which is a fully-automated shaft profiling machine. While more in line with the cost of Russ's Fit2Score software, it provides every level of detail a golfer could want to know about a shaft. Bend profiles of specific shafts are easily compared in their shaft database. Invaluable resource for the fitter or player that wants the most accurate shaft information. 

 

As with all things, you get what you pay for. 

 

I became aware of the S3 system when learning about ACCRA shafts. I'm very intrigued by it. Has anyone here subscribed to it, used it, and did you find it helpful?