Shaft measurement question

[tw_focus]

If I compare the iron shaft length as specified by the OEM (e.g., https://www.srixon.com/us/clubs/mens-golf-clubs/irons/z-585-irons/MZ585-EA.html) with the shaft length as specified by the shaft manuf., things don't always even out. For example, the 3i from that set is listed as length 39", but the 950GH shaft for 3i is listed as length 38.5" on the Nippon site (39" is for 2 iron).

 

So my question is -- is the club manuf. measuring length in a different way (maybe tip to hosel?) than the shaft manuf? Or is this just a case of the club manuf. "juicing" the club length and using shafts slightly longer than recommended by the shaft manuf?

[Stuart_G]

 

4 hours ago, tw_focus said:

If I compare the iron shaft length as specified by the OEM (e.g., https://www.srixon.com/us/clubs/mens-golf-clubs/irons/z-585-irons/MZ585-EA.html) with the shaft length as specified by the shaft manuf., things don't always even out. For example, the 3i from that set is listed as length 39", but the 950GH shaft for 3i is listed as length 38.5" on the Nippon site (39" is for 2 iron).

 

So my question is -- is the club manuf. measuring length in a different way (maybe tip to hosel?) than the shaft manuf? Or is this just a case of the club manuf. "juicing" the club length and using shafts slightly longer than recommended by the shaft manuf?

 

Neither, they are two completely different measurements.   One is the club playing length, the other us the raw uncut shaft length.   Very different things.

 

The club specs are not shaft lengths, they are club lengths.   The head and grip add to the playing length of a club so it's not just the shaft length.  How much it adds depends on the specific make and model.  It can add anything in a range of 3/4" to 2" depending on the head - although more than 1.5" is more typically only in drivers.   So 1" to 1.5" is more typical for hybrids.

 

The lengths from the shaft manufacturer are the raw, uncut shaft lengths.   They are not telling you how long they should be when they are installed, only the longest they could be.   They are actually longer than most "standard' builds will need and they expect you to cut the shaft down to whatever playing length is a good fit for you.     You do any tip trimming you want first (for parallel tip shafts only), then dry fit the shaft into the head, put it down on a club ruler and measure it out to the desired playing length, and mark the location to cut the butt down to the proper size.

 

 

 

 

Edited April 10, 2021 by Stuart_G

[tw_focus]

Thanks for the info, it makes sense. One last question -- if the shaft is going to be cut before build, why do shaft manufs. sell different length shafts specified for different irons? Why not just buy 8x shafts at 3i length and cut them all down appropriately for 3i, 4i, 5i, etc? Is there some other difference between the 3i spec shaft vs 4i spec, not just length?

Edited April 10, 2021 by tw_focus

[Stuart_G]

18 hours ago, tw_focus said:

Thanks for the info, it makes sense. One last question -- if the shaft is going to be cut before build, why do shaft manufs. sell different length shafts specified for different irons? Why not just buy 8x shafts at 3i length and cut them all down appropriately for 3i, 4i, 5i, etc? Is there some other difference between the 3i spec shaft vs 4i spec, not just length?

 

Those shafts that have separate blanks for each iron (different lengths) are taper tip shafts and/or constant or ascending weight shafts.    Some shafts do come in a single length blank that can be trimmed different for each iron in the set.  But there are some important distinctions.

 

First of all, it's important to understand that iron shafts are available with two different types of tip.  0.370" parallel and 0.355" taper.  The taper meaning that there is a small taper from 0.370 down to the 0.355" over the last 1/2" of the shaft.  Generally you need to select the correct one to match the hosel bore shape of the iron head you're installing them into.

 

The second thing that's important to know is that how a shaft performs or feels (in terms of stiffness) is largely dependent on the weight of the head attached to it.  And in order to get the same swing weight (or MOI) over a set of irons,  the shorter the club, the heavier the head has to be.   So the head weight progress in generally 7 gm increments.   7i head is 7 gm heavier than the 8i head. etc..

 

So, if one used the same shaft and just butt cut for the different lengths, then the shafts would feel stiffer and stiffer as the head weights got lighter.    The short iron shafts would play very soft and the long irons very stiff.  It would almost by like playing reg flex in the short irons, stiff flex in the mid irons and x-stiff in the long irons.

 

Now as I said before, there are some shafts that are sold in single length blanks.   In that case, you tip trim different amounts to adjust the stiffness and account for the change in weight in the heads, and then butt trim to length.  For reasons that are probably obvious, those types of single length blanks are only going to come with the .370" parallel tip.   You can't generally tip trim a taper tip shaft since you'd be cutting off the tapered part of the tip.  (Side note, for graphite shafts you could actually add the taper back onto the shaft but you can't with steel shafts).

 

The other potential downside to the single length blank concept is that the cut shaft weight would get lighter and lighter as you cut more off it so the long irons would have heavier shaft weight than the short irons.  This is actually the opposite of what is considered ideal.  This is known as a descending weight shaft (shaft weight descends as you go from the long irons to the short irons).   But the positive side is that it's less expensive to design and manufacture and maintain inventory so it's still done quite a lot, especially in the less expensive shaft offerings.

 

So here is one example of the single length blank.  It only available in .370" parallel tip and only comes in a 40.5" uncut length

 

https://www.golfworks.com/true-temper-elevate-95-vss-355-golf-shafts/p/tt0149/

 

So to deal with those issues, the shaft manufacturers will actually individually design the weight and stiffness for each iron.  The 7i shaft (which might have an uncut length of 38.0") will be designed slightly stiffer and a usually a bit heavier than the 6i shaft (which might have an uncut length of 38.5").  And so on through the set.  These we call discrete length shafts.

 

Here is the taper tip version of the same shaft:

https://www.golfworks.com/true-temper-elevate-95-vss-355-golf-shafts/p/tt0149/

 

So to sum it up:

1) Taper tip shafts will always be discrete length.  

2) Single length will always have parallel tips but parallel tips dont' always have to be single lengths,  you can have discrete length parallel tips as well as discrete length taper tip shafts.

3) Discrete length shafts can be ascending, descending or const weight (although it's rare to see them in descending weight).

4) Single lengths will always be descending weight shafts.

 

 

 

Edited April 11, 2021 by Stuart_G