Purred Shafts

[Nard_S]

@Stuart_G, good read and like the discussion on this.
I would point out that a couple things:
Forming the shaft does not leave a perfect round cylindrical shape. With a 3 pointed micrometer it's measurable to see it though it is quite small (.001"total). As good as the induction process is and any heat treating thereafter, the material there will not be exactly the same as the rest. Also not a coincidence that the measured high point in shafts is predominantly there. Also, raw material in of itself has internal stress in it. Those are introduced at the ingot level. 99% of time iits not an issue but it can be especially when heat treating is re-introduced.
So yeah, strong axis can be anywhere for a number of reasons but from the several shafts I tested my correlation has been 100%. But yeah, verify it.
The issue of oscillation can seem pretty petty and somewhat worthless. However, when you a see a Lexi Thompson have 30 cm of fore/aft bend and 40 cm of droop with driver and then think about the micro seconds of club to ball contact, maybe it's not so ridiculous to contemplate it all.
Thanks for your input.

[Stuart_G]

@Nard_S said Forming the shaft does not leave a perfect round cylindrical shape.
I know. The final imperfections in the shape play a role in any asymmetric bending properties. But that still has nothing to do with any welding seam.
@Nard_S said As good as the induction process is and any heat treating thereafter, the material there will not be exactly the same as the rest.
When Tom said that the process results in a seem that x-rays can't even detect, that's not an expression or an exaggeration. If you don't want to believe it that's up to you but don't expect anyone to simply take your word for over an industry expert without a lot more substantial evidence to back up your claim. Now I don't pretend to be an expert myself, but as an M.E. I have taken enough material science classes to know that with the proper processing, yes it is perfectly feasible that it can end up the same.
@Nard_S said The issue of oscillation can seem pretty petty and somewhat worthless. However, when you a see a Lexi Thompson have 30 cm of fore/aft bend and 40 cm of droop with driver and then think about the micro seconds of club to ball contact, maybe it's not so ridiculous to contemplate it all.

FWIW, while I don't do it myself, I'm happy to help out those who do want to do it to make sure they at least do it correctly - which is the only reason I got involved in this particular thread.
The question of whether one should bother checking for and aligning a spine is really a separate discussion I don't usually participate in. It's a subject for which there is very little good quality evidence to support either position. There is just too little hard data on how does the asymmetry in the shaft effect the impact and delivery? How does it effect the feel of the shaft? How much asymmetry does it take before there is any effect on the results? But one thing that is clear, is that the amount of bend during the swing is a function of the overall stiffness, not the asymmetry. So if you really think the strong axis is important and stiffer is better, just get a shaft that's stiffer overall. Yet that rarely happens (few fit and get the best results with the stiffest shaft ever made). Second, whether the behavior is asymmetric or not, in theory at least, a consistent swing should still produce a consistent loading and unloading response by the shaft and therefore consistent results. But that's just very basic elastic theory and there is no such thing as perfect elasticity or a perfectly reproducible swing, so that is certainly an oversimplification. The real behavior of a shaft during the swing is extremely complex dynamics. There really are no simple answers or intuitions that will really have any actual merit to support them.

However, the few times I do get involved, I like to ask one question. The following graph (from the Tutelman site) is a real recorded example of how a shaft bends over time during a swing relative to it's bending axis. As you can see, it's not limited to a single axis but rather covers almost a full 270*. The question is: what makes one axis so much more important than all the other axis that aligning the spine will noticeably improve the results? And it what way exactly are those results improved? Some have argued that if there is enough asymmetry, then the spine alignment can effect the feel. While I don't doubt that at all, that still leaves the question of which axis does the feel come from? Which is more important, the feel of the shaft loading, or the feel of the shaft unloading? Because they happen on very different axis. Scientifically, they are all very interesting and even valid questions to ask. Unfortunately, finding answers isn't so straight forward.

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[Howard_Jones]

Everytime this can of worms is opened, i ask myself, should i participate or not?
Ive been using FLO combined with a CPM reader since day 1, and ive been using it as a quality control of both asymmetry and flex strength so i know that the shaft pick for the player is as close to the shaft used during fitting as possible, so for me, this has nothing to do with shaft behavior, but to get specs of 2 shafts equal. My reason for using FLO is that the CPM reader has a easier job to measure a shaft on its FLO lines vs a position where it osilates like crazy, its simply way harder to get a constant reading outside this 2 axises, but i cant claim that FLO lines itself makes a difference for the player, i have no evidence to support that, but on the other hand, it does not seem to make things worse either, so i do use this FLO lines for install, and all my DEMO/Fitting clubs was installed the same way.@Nard_S
Ive seen the same words you are using several times (welding seem and spine), but sorry, its a myth. The way steel shafts is made "neutralize" the welding seem, so there is no rules here, the strong vs the weak FLO lines is not related to where the welding seem is. For graphite shafts, i never saw a system that say label up or down is where the strong or weak FLO line is, it vary just as much as it does on steel shafts, it could be anywhere, but some happens to have good flo at least close to "label up or down", but never as a constant, so we have to find it using a CPM reader if we want to install the shafts using the FLO lines.
Her is a small compare of 13 shafts i measured to make a example of this years ago, so many has seen it before. Flex strength might vary quite alot between 2 shafts of the same model and flex, and thats the reason for why i always measured them to know what shaft i had at hand. Label up or down is the same axis, 6 of 13 shafts had "good FLO" in this position, 7 did not, so its no system to it, neither for if that position is the weak or strong when it does FLO good in that position.
So, my take on this is, FLO with CPM is a quality control to make sure we know what shaft we have at hand compared to the shaft used during fitting, nothing else, and i did the same with steel shafts where i took advantage of differences for Flex matching, but not because i think it makes a difference for the players ability to make a good impact. In cases it does matter, i relate it to feel and flex itself, not how that shaft oscillates since the ball is gone after the first time the shaft has bend back and forward again, and like Stuart writes using a example from Tutleman, all this happens while we rotate the shaft at least 90* from one FLO line to the next, so if this FLO lines was important, all positions in-between those 2 FLO lines should be just as important, but hardly no shaft has good FLO no matter install position.
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[Nard_S]

Ha ha, I really stepped in it. Good stuff though. I will back off the label thing, there is some randomness to it though there is grouping too. As far as a seam or better, temper line, it's there, it's also highlighted by bump of diameter. I will get back to this with more in depth showing of it. How this translates to club performance, especially in light that there's a twang in two planes leaves me stumped. So I get the shrug that many have with this. Thanks.

[Nard_S]

 

This is a split open NOS Rifle shaft. On the left a temper line can clearly be seen (look it's corroding too, yet induction weld does not effect, hmm) not surprise that egged high diameter is also over seam and that truest wave of "flo" were there too. KBS & TT shafts show this too. Nippon has one of the cleanest. Doing S.P. Blue set now, they are extremely consistent, off axis to on axis deviation is minuscule but it is there. Of 4 done, seam, high point & strong axis align, however have one yet to do that has seam at low point of diameter, so that will be interesting. As to screened labels and strong axis? Simply not enough correlation, some tendency but not exact. Aldila shaft done was within a few degrees labels. But on balance pay no mind.

How does this come out in the wash? Probably to not much. The effort of concise weight & lengths probably mean a whole lot more but it's a detail and details can compliment & crown core of effort.

 

[Nocklausd]

I bought a 3 wood of a friend who did not like the club. It did not work for me either, chunked it all the time. So I FLOed it and turned the shaft 90 degrees getting the softer bend towards the target and a stiffer/smaller droop bend. After that I just love the club.

So, for me it definetly works ...

 

Nocklaus

[gunmetal]

This. And honestly, the placebo effect is real. People who take sugar pills actually can show physiological improvements relative to whatever they are measuring. In golf more than any other sport, if you feel like you are benefiting from something and it's not cost prohibitive, then do it. I feel like Mizuno irons are better than Ping. They aren't. But for me, you better believe I play better with Mizuno irons, lol. I've had a lot of personal experience with FLOing shafts. I purchased the plans to Dave Tutleman's Neufinder 4 and built the machine. It's fascinating and I experienced with all sorts of setups. In the end I can't wrap my mind around the ever changing dynamic action of the shaft to comprehend how there would be a TANGIBLE benefit to performance (much like Stuart and Howard have articulated). But if buddies want me to "Pure" their shaft, I happily do and I legitimately love hearing how their new club is amazing ever since "Jake fixed it up".

[Buzzkill]

Love post, agree!