“Flighting” Golf Shafts

Before we touch upon our topic of “flighting” golf shafts, when need to first look back at last week’s blog where we showed you how certain shafts can be trimmed in multiple ways to create alternative flexes.  This process allows club fitters greater latitude in producing in-between or custom flexes for their clientele.  In the case of the KBS Tour, you saw one shaft could be used to create a range of flexes and in some cases this produces flex overlap.


FCM Range


4.0 – 5.5


5.0 – 6.5


6.0 – 7.5

For instance, if you wanted the equivalent of a 5.5 flex, you could elect to take the R or the S flex shaft and then follow the appropriate trimming table as we will show shortly.  While the X flex range may appear too stiff to create a 5.5 flex, I am going to let you onto a little secret.  Actually it is no secret at all, we are just applying the principles we learned in the previous article.  We know in order to create a 6.0 flex we would take the X-flex blank and use the following trim chart.

Using the Principles in Reverse
One of the questions you may ask in the back of your mind is how many golfers still use a 1 or 2 iron (or even hybrid) anymore?  The answer is few.  So what if we started with the 3-iron and took 1” less off of the tip than what is suggested?  We learned that cutting 1” additionally increased the FCM level by 0.5 (5 cpm) or ½ flex.  Therefore, if the opposite would occur by leaving an extra inch from the tip, we should see a reduction in the FCM level from 6.0 to 5.5.  Now we have three different shafts that could literally produce the exact same frequency numbers and slope.

Concept of “Flighting
Just because we produced the same frequency numbers, does this mean we produced the exact same stiffness?  The answer to this is a big “NO” and here is the reason why.  A golf shaft is a hollowed tapered tube.  This stiffness is defined by many parameters such as the weight, wall thickness and outside diameters of the shaft.  One of those parameters you can see quickly on a stepped steel shaft is the distance of the parallel tip section or the distance to the first step.

The raw, uncut R-flex KBS Tour shaft had a parallel tip section of 12”, the S-flex 11.5” and the X-flex 10.5”.  However, if we followed the trimming instructions from the previous chart, you will notice how the parallel tip section changes.  While the R-flex appeared to have the longest parallel tip section, after our aggressive tip trimming to increase the stiffness to the 5.5 FCM level, we have much less parallel tip section remaining as this chart will show.

On the other end of the spectrum, the X-flex blank had the least amount of parallel tip section in the raw, uncut form.  However, we opted to tip trim less off of the shaft to create a softer (5.5) frequency level.  Here’s the skinny, if you have two similar geometry shafts with the same frequency, then the one with a shorter parallel tip section should provide a lower trajectory as the tip will be stiffer.  Conversely, a longer parallel tip section with very similar geometries will produce a softer tipped section and subsequently a higher launch angle.

This is how “Flighted” shafts are produced to be able to offer higher launching shaft in the long irons for ease of play, mid launching in the mid-irons and lower launch in the scoring clubs by a manipulation in tip trimming of different flex blanks.  Some may say these have progressive bend or kick point, but it is really manipulating the parallel tip section that is creating these changes.

You cannot do this with any unitized, parallel tipped shaft.  Rather, the manufacturer has to produce a series of blanks that are nearly identical other than the raw, uncut frequency (stiffness) and possibly weight.  Few manufacturers are going to do this because of cost and the reason why these types of shaft demand a higher selling price.

This is a good exercise in understanding the effects of tip trimming on shafts and how you create differences is initial ball flight or trajectory.  Secondly, this is one reason why you might see an R-flex shaft create a higher ball flight versus the same exact shaft in S-flex.  Lastly, this illustrates why two clubs of the same length and frequency (stiffness) don’t always play or feel the same.


  1. Paul says:

    Great informative article. Thanks.

  2. Mike French says:

    Jeff, Interesting article with lots of useful information. One of your closing statements, along with examples given earlier got me wondering ..If I wanted to create a flighted-like set of irons out of unitized, parallel shafts, why not start with 3 each x-stiff, stiff and regular flex shafts and use the regular flex for the long irons (higher flight) the stiff for the mid-irons (medium flight) and the x-stiff for the short irons and wedges (low flight). Based on the information you gave last week (in the KBS article) I could manipulate the tipping of each shaft to give me a consistent flex through-out the set but change the flight characteristics of each iron based on the wall thickness of the shaft I use for each club and the amount of tip I remove. I’ve never built an entire set with this goal in mind, but I have used different initial flex shafts to create individual clubs with specific ball flight characteristics for certain customers. Your Thoughts?
    Thanks for doing such a great job of keeping all of us informed and forcing us to think in new ways.

  3. Jeff Summitt says:


    I would probably need to know which shaft you are trying to use first. For instance, if it was a Dynamic Gold where you have all 3 flexes, you would end up with a standard ball flight by creating a set where the frequencies increased at 4-5 cpm per 1/2″. That is, you would be taking the R-flex, which had a longer parallel tip section than the S-flex. But in the long run, you could have easily used the S-flex and created the same thing. The key is the parallel tip section as well as the manufacturing blanks in which “flighting” would be possible.

    The other alternative to “flighting” is to do what True Temper did a while ago in their Tri Gold set. Instead of 4-5 cpm per 1/2″ progression in frequency, it was more like 8 cpm. By virtue of a softer flex (frequency) in the long irons, the ball flight would be higher and stiffer in the short irons would reduce trajectory.

  4. Jim says:

    Could something similar be achieved by “soft stepping” the longer irons and increasing the increment until the short irons are tipped as recommended? For example, I’m using a set of Apollo Stepless steel shafts.

    Recommended tip trimming for STIFF flex:
    5i(2″), 6i(2.5″), 7i(3″), 8i(3.5″), 9/PW(4″)

    If I want longer irons to play progressively softer than the scoring clubs, can I tip like this:
    5i(1.5″), 6i(2.1″), 7i(2.7″), 8i(3.3″), 9/PW(4″)

    So, my 5i is tipped midway between R/S flex, and each shorter iron in the set moves progressively closer to S flex.


  5. Jeff Summitt says:


    In theory yes, but the difference in 0.2″ or 0.3″ will be pretty small to see much, if any, change in the actual trajectory.

  6. Jim says:

    Thanks for the quick reply, Jeff!

  7. Chuck says:

    Hi. Great article. I bought a set of new pulls KBS Tour 90 and was searching to find raw tip length so I could check the tipping before installing. Stumbling on to this article and the previous about multiple flexes with the parallel tips was a bonus. Yet I still do not know the tip lengths (uncut) in the 90. The KBS trim charts confuse me as the flex on the Tour for stiff is 5.0 to 6.0 and the Tour 90 is 4.5 to 5.5. Coming off the Tours and changing to the 90 I want to get the 5.5 feel of the Tour in the 90 and have no clue how other than starting firm and soft stepping. Having to regripping every time and purchase another shaft. Did all that with the Tours and would hope to not have to repeat it again with the 90. I am thinking the 90 is advertised to give a higher trajectory with the same spin as the Tour in a lighter shaft. Do they accomplish this by calling a R+ a stiff? And the thinner wall shaft you would think the cpm would have to be higher to feel the same as the Tour.

  8. Jeff Summitt says:


    If they are the 0.370″ parallel tip version, the raw tip to first step length is 12″ on R-flex and 9″ on S-flex. The KBS Tour 90 hits the ball higher than the standard KBS Tour due to being more flexible overall (thinner walls). CPM is CPM, rather than going by the generic letter flex code so use that as your guideline.

  9. Grim says:

    I’m gaming a set of steelfiber i95 regular shafts and find it difficult to play in the long irons. Base on your article, would soft stepping the shafts in the long irons help, and with these shafts, how much do I need to soft step to see results?

  10. Jeff Summitt says:


    When you say “difficult to play”, is this getting the ball airborne or making solid contact? If it is the latter, then you might consider a length change or a switch to a hybrid. If it is getting the ball airborne, then soft-stepping might help depending upon how much trouble you are having. The only real way to tell is to take the shaft from say the 3-iron and move it to the 4-iron. I would not even remove the grip and cut it down yet but rather choke down the 1/2″ to simulate the length. If that does the trick, then it will be easy enough to alter the length. Remember, for each time you soft step, this will mean you will need to purchase a longer raw length for the lower lofted irons.

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