shaft flex

[2irondude]

After 10 years with my T zoid pro 2 irons I am going to order new Mizuno irons next week. I am going to order the irons .5 inch longer. I asked the club fitter how the ordering longer irons would impact the flex for the Project X or the KBS shafts. He did not know? He said it would make the club heavier but he was not sure if a longer shaft would change the flex.

Does anyone out there know the answer? I need to find out before I order the set.

 

[Alastair Gibson]

2IRON,

The general rule with shafts ( I certainly know this to be true for dynamic gold shafts) is that for every inch longer that shaft becomes its stiffness lessens by half a flex, ie 2 inches longer would turn a stiff shaft into a regular, however it is slightly dependent on whether the shaft is left longer at the tip end or the butt end. In general though it will turn a shaft marginally weaker.

The reason for this is that physics dictates that a longer shaft with the same forces exerted on it will bend slightly more than a shorter one.

As for swingweight, each half inch longer a shaft is will take swingweight up 3 point (ie from D1 TO D4), however, i believe that Mizuno fit slightly lighter heads to custom ordered clubs that are fitted with longer than standard shafts to prevent the swingweight feeling very heavy.

Hope this helps

Al

 

[mjtoal]

Mizuno will use a lighter head weight to make the club play true to flex and swingweight.

 

[Mizo]

All other club components staying the same, switching into the KBS Tour shafts from other tapered tip shafts will often equate to a drop in swing weight by approximately 2 points (i.e.: D2 to D0). This is a result of a slightly higher balance point of the shaft which allows club builders to insert more mass in the clubhead or add up to ½” to the club length to maintain the same overall swing weight.

Straight off their website, so that's at least something to take into account.