Thursday, October 4, 2012

A Look At Single Length Irons

Recently a golfer over at the Wishon Golf forum (www.wishongolf.com) asked about single length irons. This is where each iron in the bag, regardless if it’s the 3-iron or 7-iron or Pitching Wedge, will be the same length.

In 1989, Tommy Armour Company came out with this concept in their EQL (equal length) model of irons.


Each of the irons, 3 thru Pitching Wedge, was built to 37 inches long. That is about the length of a modern 7-iron. Back in ’89, that was probably the length of a club somewhere between a 6 and 7-iron. The idea behind the irons was to get the golfer to make the ‘same swing’ with each club. It was considered too radical and had too many flaws involved with the concept for it to work. Here’s what Keith Chatham, from Precision Fit Golf in Texas had to say:
Assuming shaft weright and grip weight are the same:

Problems:

All head weights need to be same weight or else swing weights/total weight/moi will be off......long irons will be very light swing weight and short irons will be very heavy swingweight.

All lie angles need to be the same for each head also or else accuracy will be sacrificed.

Distances will be off with current lofts also. Assuming all clubs are 7i length, then the 5i at 7i length might be shorter than your current 5i, and PW at 7i length might be longer than your current length PW. So lofts probably will need to be adjusted.

Bounces on sole will be the same for all clubs except maybe 3/4 degrees more for SW. So when adjusting/bending clubs for loft, you need to make sure you don't have a scoop sole on long irons or way too much bounce on your shorter irons.

Benefits:

Only benefit I see is you might hit the shorter long irons more on-center, however the problems above will still exist.


I generally agree with Keith’s points. I would think the benefit is that it would be more easier to MOI match the clubs if they were the same length. What would concern me is that in order to do this, the head weights would have to be the same. And companies do not make iron heads the same weight. Here’s a link to KZG Golf’s set of irons with their iron head weights.

http://www.kzg.com/sites/courses/layout9.asp?id=588&page=37679&sid=1153

You will see the same with other component companies like Wishon and GolfSmith. I do believe golfers and clubmakers should not only understand MOI matching, but also understand how much each of their components of the club weigh (grip, shaft, head).

And to top it off, if you can understand the shaft’s weight distribution…does it weigh more towards the butt end or towards the tip end?…the golfer and clubmaker can find a better fit.

With the single length concept, I would question if the grind, bounce and general design of the heads would ‘naturally’ cause for the higher lofted clubs, which also have more bounce, to be heavier. Edel Golf’s wedges feature extremely high bounce angle options with the CoG of the club moved away from the heel.


In order to design the wedge heads with more bounce and moving the CoG away from the heel, I was told that they had to make the heads heavier.

I have typically found that Sand Wedges at 54-56 degrees of loft typically weight around 302 grams. I measured my Edel 56° wedge at 307 grams. And yes, 5 grams of difference can make a LARGE difference in how the club feels when you are swinging it.

Anyway, my point is that I have some concern that the higher the loft of the iron which should require more bounce, that irons should inherently have a progressive weight to them and that the irons should inherently have different shaft lengths to ‘offset’ the difference in head weight. Then I would question other things, mainly yardage gapping and if a single length set of irons would need to alter their loft increments in order to get the proper yardage gapping.

A special thanks to Keith Chatham (www.precisionfitgolf.com) for help with this post.









3JACK

4 comments:

mike said...

tutelman has an interesting analysis of this.

http://www.tutelman.com/golf/clubs/OneClub.php

Jaacob Bowden said...

Here's some more info about same length irons -> http://www.swingmangolf.com/1ironGolfClubs-myOstrichGolfPureFitiMatchSL-SameLengthClubsReview.asp

Welcome! said...

I shot 82 with this set of irons when I was 12 in 1997.

GreggP said...

Seems to me that the problems mentioned relating to single length irons are nothing more than the same type of engineering problems club designers face each time they set out to modify an existing design, or create a new club.
I have only a layman's understanding of engineering, but I would hypothesize that having the same weight and lie angle for every club, would give them a head start on the design process.