Same length irons

[holmesy-XLS]

Just wondering what people think about having all there irons the same length. It makes sense in theory to me but i just dont think it would feel right, and take the challenge away from golf. have a look here

http://www.1irongolf.com/

[Ferrins]

should be called
http://www.gimpgolf.com/

[Jono]

Ask kwantfm. I think he tried this once.

[kwantfm]

It's a long time ago (6 or so years ago) and I tried a variation of this. Like most I have no problem with the shorter irons. So I built a set where all clubs 7-iron or shorter were standard length. This makes it easy because building longer short irons is difficult given you have to find light heads (not standard and not easy to find). I then built irons up to 3-iron which were bent to 7-iron lie and weighted to 7-iron weight and all had the same shaft set up. This worked pretty well. pinglauncher says to this day that they are the best feeling set of irons he has ever hit (they had Nippon 950s in them for reference and I used Wishon forged heads so they could be bent easily and had weight ports in the hosel).

My take on the long irons was that I launched them lower, with less carry and more roll. They went straighter but I couldn't tolerate the lack of height.

T

[Dotty]

A poster on another forum tried this a year or two ago. From what I can remember, it only worked for the middle irons.

The short game (chips, lobs, sand) became too cumbersome and he reverted to standard length wedges.

And 3i, 4i and 5i didn't have much difference in distance, due to losing the extra leverage of a longer shaft for a lower loft.

[Oldplayer]

I have never tried this system but it just sounds like a gimmick and something that would not work well in practice. For eg. the shorter shaft of a pitching wedge promotes a steeper more upright swing which is exactly what you want for producing solid wedge shots. Conversely the longer 3 iron shafts promotes a flatter, sweeping swing which is helpful in a good long iron strike. This sort of knowledge is not rocket science, it is common sense and only one aspect of why different shaft lengths work well in the game of golf. That is why I am surpised that anyone would take 1iron golf seriously.

[markTHEblake]

Here is the article that Dave Tutelman (what he knows about golf clubs makes Virge seem like Golfer69)
http://www.tutelman.com/golf/clubs/OneClub.php?ref=

conclusion
I feel that a 4- or 5- through 7-iron with the length and mass of a 7-iron could be a big help for some golfers. But longer clubs than that should be replaced by hybrids or metalwoods, and shorter clubs are more advantageous in a conventional design.

[razaar]

Tuner (Chris McCourt) mentioned to me one day about a club fitter in Townsville who was advocating the same shaft lengths through the iron set as his interpretation of an easier way to MOI match a set. MOI matching gives each club the same feeling at takeaway and at the transition of backswing to downswing (the two moment of inertia in a golf swing). Having the same shaft length when the heads get progressively heavier (from the low lofts to the high lofts) doesn't make any sense within the concept of MOI matching.

[Tomson]

My dad tried it from 1irongolf and said it didn't do his golf game any favours. I have read other people talk about it and say how good it was. Different horses different courses.

[virge666]

#1 The heads are not designed to be used this way - so why go against the way clubs are designed.

#2 is that no professional golfers do this - so if the best in the world won't even try it - why should you.

#3 is that you won't get enough clubhead speed in the long irons to get the ball up as it is designed... so don't do it.

#4 is that you will have to much clubhead speed in the shorter clubs . . . so less control when you need it.

Just go and play the game . . .

[3oneday]

He's 14, I doubt he was. He was just interested in the concept.

[Jono]

MOI matching gives each club the same feeling at takeaway and at the transition of backswing to downswing (the two moment of inertia in a golf swing)

Raz, is this what chris told you? I hope he was joking ...


MOI (ie. moment of inertia) matched clubs ONLY feel the same when you waggle the club from the pivot point where the MOI is taken from. Some people use the butt of the club as the pivot point. Some use the point between the left and right wrist as the pivot point. the point is, matching the clubs only by MOI will NOT give you the same feel during the takeaway or at the transition because the club is not rotating about the wrist axis at this point.

If you really want the clubs to feel the same, you have to match the clubs by weight, first moment (mass times radius), and second moment or MOI (mass times radius squared).

the only way you can do this is either make all the clubs the same length with same head weight OR add some weight along the shaft.

IMO, neither method works that well.

[razaar]

Jono

Wouldn't think so because he has spend big $$$$'s on Wishon's computer software to MOI sets. He has been doing it for quite a while now; he does John Senden's clubs and those of many Qld pros. I don't fully understand how it works but it relates to the two Moment of inertia in the golf swing, namely the force which breaks the inertia of the clubhead at address and the force that breaks the inertia of the clubhead from backswing to forward swing. Making sure that the clubs swing identical to each other in relation to these forces. Irons are not matched with woods is my understanding.

[Jono]

I'd love to see his formulas ... Moment of inertia doesn't actually mean a moment (as in moment in time) of inertia (as in stillness). Moment of inertia is an object's tendency to resist rotational motion just like mass is to linear motion. So moment of inertia of a club matters most when it's moving fast (ie through impact), not when it's moving slowly.

For example a typical driver with 200g head and graphite shaft has a higher moment of inertia (second moment) than say a 9 iron. 9 iron is heavier than the driver and has a higer first moment (ie feels heavier when you hold it out horizontally). So whilst it takes more force to lift up a 9 iron than a driver, the driver takes more rotational force to release because of its greater tendency to resist rotation.

As I understand it, Tom Wishon's software only matches clubs by moment of inertia (i.e. second moment).

BTW, matching a set by swingweight doesn't actually match anything. It's matching a set by first moment about the point 14" from the butt of the club. If you look at the swing weight scale, the fulcrum is 14" from the butt end of the club.

Whilst swingweight matched set is not really matched by anything meaningful, it does give a smooth transition: the first moment and weight goes up as the clubs get shorter and the moment of inertia goes up as the club gets longer. This means the golfer does have to make a different swing from club to club but it is PREDICTABLE.

[razaar]

There are different types of MOI, Jono - Wiki will provide the definitions of each. The Wishon computed system takes into account club weight, shaft length, swingweight, head weight, frequency revs, etc of a particular club that fits your specs (usually your favourite club) and provides the info on what is required to match those specs through the irons or the woods.

[Jono]

There are different types of MOI, Jono

How many different types are there?

The fundamental concept of moment of inertia is a body's tendency to resist rotation about a certain axis.

I got this formula from Wiki as you suggested.





"I" stands for moment of inertia.
"m" is the mass of a point source.
"r" is the distance from the center of rotation to the mass m.
The curved line is the integration sign.

So Moment of inertial is definded as a sum (or integration) of all point's mass multiplied by r^2.

You can have different MOI formulas for different shapes (eg sphere, rod etc) but they all derive from the above fundamental definition of MOI.

So I'm curious when you say that are "different types of MOI". Is Chris measuring different MOIs about different axes?

[bebo]

ozmaths.net

[3oneday]

more like whatthe****isthat.net

[ddasey]

[razaar]

Here we are Jono, this may explain the different MOI's in golf. Lets hope so anyway...was never very good with mathematical formulas. Wishon's site may have more info...its really not my thing.
http://golf.about.com/od/faqs/f/moi.htm

[Jono]

Here we are Jono, this may explain the different MOI's in golf. Lets hope so anyway...was never very good with mathematical formulas. Wishon's site may have more info...its really not my thing.
http://golf.about.com/od/faqs/f/moi.htm

MOI depends on the axis of rotation. That article talks about MOI of the CLUBHEAD vs the MOI of the whole club. eg. the MOI about the COG of the clubhead (ie. higher the MOI, more forgiving the clubhead is). It also talks about MOI of the clubhead about the shaft axis. These are MOI properties of the CLUB HEAD.

Unless Chris is into designing his own club heads, I doubt that he is matching these clubhead MOI values across the set.

When a clubmaker (eg Wishon) is talking about a MOI matched set, it usually means the MOI of the club about the wrist axis (ie. how much a club tends to resist being "released")

MOI matched clubs about the wrist axis, unless it is also matched by total weight and first moment, will NOT feel the same during the slow stages of the swing (eg takeaway and transition). Where they might feel similar is when the club is moving fast (ie. through impact).

[razaar]

The swing around an axis is a given in golf. The only time inertia comes into play is at the start of the swing (breaking the inertia of the clubhead at rest), at the completion of the backswing (stopping the inertia of the clubhead in motion) changing the direction of the clubhead. Both points are when the clubhead (at rest & in motion) is changed by an external force (the golfer). An advanced golfer with a repeating & timed swing will benefit by having a matched set of clubs that feel exactly the same at their slowest points in the golf swing (the start and at the top) where the club is unstable and easily moved off plane). At speed the clubhead is very stable and tracks on plane. That is my understanding of MOI matching clubs.
Perhaps we are saying the same thing but in different contexts.

[Jono]

Ray, why don't we chat about this in person over a beer at the champs? It's much easier to expain in person.

If you want to match the feel during the slow parts of the swing, you are better off matching the set by weight and the first moment (ie. mass times radius).

The club's "stability" is not altered by MOI matching.

[henno]

Ray, why don't we chat about this in person over a beer at the champs?

Note to self: Be very far away from these two when this conversation happens, or risk a brain 'splosion.

[Oldplayer]

Note to self: Be very far away from these two when this conversation happens, or risk a brain 'splosion.

I'm with you brother!!
Whatever happened to just hitting the dam ball?