Robert's Fantasy: Frequency Match?

[rhh7]

Assume I use Dynamic shafts, R/S flex, 133gms raw weight, 43" long, with 12.5" tips.

I will not tip any shafts, only butt trim to correct length. My grips will weigh 58gms.

iron loft lie wgt/gms length
5 28* 59* 254 38.0"
6 32* 60* 261 37.6"
7 36* 61* 268 37.2"
8 40* 62* 275 36.8"
9 44* 63* 282 36.4"
P 48* 64* 289 36.0"
G 52* 64* 289 36.0"
S 56* 64* 300 36.0"

How close would this set be to being frequency matched? What would be the cpm's for each club?

I have had a wonderful time reading through the posts and threads on FREQUENCY and on MOI. I am still quite confused as to how it all computes.

Thanks a million!...Robert

[Chieflongtee]

If you do that you will end up with a set with the same frequency across the set. It is called single frequency. Frequency matched means something else. My guess is if you go ahead you'll end up with a requency between 290-300 cpms providing each shaft is cut in half inch increments and if the components weights are pretty much bang on. Go through the following site for a better understanding.
http://www.swingsync.com/

[BC MIST]

If you do that you will end up with a set with the same frequency across the set. It is called single frequency. Frequency matched means something else. My guess is if you go ahead you'll end up with a requency between 290-300 cpms providing each shaft is cut in half inch increments and if the components weights are pretty much bang on. Go through the following site for a better understanding.

v. matched, match·ing, match·es
v. tr.
1. To be exactly like; correspond exactly.
2. To be like with respect to specified qualities.

If you are still playing with the irons that all have the 292 cpm frequency, then you are playing a TRULY matched set. Mine are all matched at 301 cpm's and the MOI is 316643. Again they are truly matched by both frequency and MOI.

Clubs that have a sloped frequency and/or have different MOI numbers are MISMATCHED. I know that if there is a constant difference in flex between irons they are traditionally called MATCHED, but they are not. The swing weights of a tradition set should all be the same, making them matched, while the swing weights of an MOI matched set are all different, which is good, because having clubs matched by how you swing them is more important than by how you waggle them.

The last truth is that most golfers play with clubs that are almost completely mismatched because they have different lengths, different frequencies, different MOI's, different weights, different lies, and different lofts. They are matched only by swing weight and grip weight.

[Chieflongtee]

Robert. Do you have a swingweight scale. I noticed your club lengths are in different increments which means you are trying to produce a MOi matched set as well. It is a lot easier to build such a set using a swingweight scale.

[rhh7]

Robert. Do you have a swingweight scale. I noticed your club lengths are in different increments which means you are trying to produce a MOi matched set as well. It is a lot easier to build such a set using a swingweight scale.

I would indeed like to have a set which is matched as to frequency and to MOI. I am indifferent to swing weight.

It seems that Dave Tutelman recommends making each longer club 1/2 swingweight less. I can get access to a swingweight scale, but don't really understand how to do this.

[Chieflongtee]

I would indeed like to have a set which is matched as to frequency and to MOI. I am indifferent to swing weight.

It seems that Dave Tutelman recommends making each longer club 1/2 swingweight less. I can get access to a swingweight scale, but don't really understand how to do this.

I believe it is 1/2 sw more. http://tutelman.com/golfclubs/MOImatch.php?ref= You can do this by either adding some sort of a weight(lead tape,tungsten powder or what have you) or by making the shaft a tad longer.

see this
http://www.freegolfinfo.com/forums/tm.aspx?m=1924805
That is one of the reasons the KE4 and other weight adjustable irons are great. You can find your ideal sw by using impact decals and lead tape.(start light and build up) Once you consistenly find the centre of the club face with the longest club in the bag you use this as a starting point and build up the progressive swingweight from there.
When you are done have your lies checked.

There are other methods but this is by far the simplest.

[Chieflongtee]

v.
. Mine are all matched at 301 cpm's and the MOI is 316643. .

316643. Explain the number . Is that from Jorgensen's formula? Or wishon's? Or someone else?

[jvincent]

Chief I think that is a Wishon number, in units of kg/m^2, but I'm not sure.

Now I have to be careful with the following since my math has been questionable of late, but if you look at the equation for the period of a pendulm, as shown in the following link, anyone can make a very simple MOI matcher. Important to note that it's a MATCHER and you'll have to do the math to calculate the numerical MOI.

http://online.cctt.org/physicslab/co...ums/period.asp

Assuming you want a constant MOI, then the two variables in the equation become T, the period of the pendulum (T) and the mass (m) and center of mass of the club (L).

So, if you create a simple pendulum rig and measure T for your clubs you can match their MOI by matching their periods. To do this you will need to adjust the m*L product for each club until T matches by adding (easy) or removing (harder) weight from the club and/or changing the length of the club.

[rhh7]

[quote=Chieflongtee;139374]I believe it is 1/2 sw more. http://tutelman.com/golfclubs/MOImatch.php?ref= You can do this by either adding some sort of a weight(lead tape,tungsten powder or what have you) or by making the shaft a tad longer


excerpted from the article you cite above:

"MOI Matching

trimming to length .4" between clubs

measured swingweight: 1/2 SW Point (longer lighter)"



Doesn't this mean, for example, that if your SandWedge has a swingweight of D5, your PitchingWedge would be D4.5, your 9-iron D4.0, etc.?

Thanks, Robert

[Chieflongtee]

It would. I am just thinking rearward i.e if you start at D1 for the 3 iron then your 4 iron will be D1.5. So we are on the same page. One thing you should keep in mind though is the chosen method for choosing the favourite club. It is one thing to MOI match but matching a favourite club is better well at least until now. Dave T's matched his set to a favourite 7 iron which used to be the trend. Things have changed a bit though. See Tom Wishon's reply below:

''
Since we started the MOI Matching system in the winter of 2003, we have
been communicating a lot with some of the clubmakers who began doing MOI
matching in their shops to keep up a dialog of how best to determine
WHAT MOI is best for each golfer.

Over the past three years, we have found that the "favorite club"
approach can work, but better if the favorite club happens to be a club
that is longer than what most golfers' 7-iron - wedges would be. Basing
the golfer's MOI on a short iron can lead to error because short irons
for some golfers simply become "favorite clubs" because they are so much
shorter in length and thus are much easier from the 'get-go' for the
majority of golfers to swing with more consistency.

What we find works a little better is to complete all aspects of the
fitting analysis so that the clubmaker knows the head, shaft, trim,
length, grip/size for the golfer. Then the clubmaker picks a "test
club" to build that is at least 38" in length or more from the set
makeup being recommended. This could be an iron, hybrid or fairway
wood. By going through a process of "trial and error" using lead tape
to add to the head until the golfer either starts hitting the ball more
consistently or gets to a point where they start to sense that the
clubhead is too heavy, it is thus possible to get the test club to a
point where the golfer likes it a lot and does show a higher % of on
center hits. The MOI of the test club is then measured and becomes the
benchmark for the MOI of all the other clubs in the set.

Whether to make the MOI the same for all woods and all hybrids/irons is
a point in MOI matching that we feel is still up for debate. We've
heard pros and cons in both ways from clubmakers who have been seriously
working on MOI matching in their fitting work. So we'll keep watching
and messing with this as time allows.

TOM

[Chieflongtee]

Chief I think that is a Wishon number, in units of kg/m^2, but I'm not sure.

Now I have to be careful with the following since my math has been questionable of late, but if you look at the equation for the period of a pendulm, as shown in the following link, anyone can make a very simple MOI matcher. Important to note that it's a MATCHER and you'll have to do the math to calculate the numerical MOI.

http://online.cctt.org/physicslab/co...ums/period.asp

Assuming you want a constant MOI, then the two variables in the equation become T, the period of the pendulum (T) and the mass (m) and center of mass of the club (L).

So, if you create a simple pendulum rig and measure T for your clubs you can match their MOI by matching their periods. To do this you will need to adjust the m*L product for each club until T matches by adding (easy) or removing (harder) weight from the club and/or changing the length of the club.

John. Thanks for the link. I am so bad at physics. I just wish I could go back in time.

[rhh7]

I have read and reread Tom Wishon's book, THE SEARCH FOR THE PERFECT GOLF CLUB. I learn something new each time.

My thinking is to build a set of 8 irons: from my favorite 5-iron, to 6,7,8,9,PW,GW,SW.

My 5-iron will be 38", which is the longest length which I hit well. I have not yet decided on the CPM, or the specific shaft to use.

I have always played stiffer, heavier shafts. In my younger days I never shot much better than 79. But I have always battled a hook, with a short, quick swing. I still have wrists of steel, but my neck, back and hips all hurt now. It is obvious that I need to go to more flex, and perhaps a lighter weight steel shaft.

I have never been able to get used to graphite, nor to the large head woods now in vogue.

[Chieflongtee]

Have you tried this?
http://www.shaftfit.com/shaftfit/shaftfit.swf
Prosoft inserts might also help

[rhh7]

just tried, it comes up with Dynamic Gold S300....my present irons are Rifle 7.0, but I think I want to go with more flex than this, was thinking of somewhere between 290-300 cpms.

[BC MIST]

316643. Explain the number . Is that from Jorgensen's formula? Or wishon's? Or someone else?

Explained above nicely by JV and is on the information sheet I sent to you a couple of years ago.

All of my clubs (Wishon 560's) are NOT this exact number(it's the average of the set) because you could add just 1 g to the head weight, for example and the number would change 1263. However, the difference between the highest and lowest is about .5% which is considered a good match.

My other set (Wishon 550M's) had a .25% MOI match. Interestingly, you guys have talked about having a .5 SW point difference and a .4" difference in length to get a match. My mathematically calculated swing weight results from this set are as follows:
4 - C8.0
5 - C9.6
6 - D0.4
7 - D1.2
8 - D2.3
9 - D3.1
PW - D3.9
AW - D3.9
The lengths were .4" apart except that the PW and AW were .35" from the 9.

This method that I use allows me to be reasonably precise, to .1 g head weight and I actually grind the butt end of the shaft to final playing length. While it is not necessary to be this exact, if I can, why not? The major problem is putting my imperfect swing on these perfect clubs.

[Chieflongtee]

BC. I believe your method yields different sw results because in your case weight is added to the butt end underneath the grip. Am I correct?

[jvincent]

As I recall from Dave T's articles the 0.4" and 1/2 SW point guidelines assumed "typical" length/weight steel shafts, grips, and clubheads.

If you were to use much lighter shafts I'm pretty sure the guidelines would be different and BC uses double XXL grips if I'm correct so that would change his numbers.

[BC MIST]

BC. I believe your method yields different sw results because in your case weight is added to the butt end underneath the grip. Am I correct?

No/Yes
No. My last three sets were done by adding weight to the head only, and I liked them all.

Yes. For my first set, I also matched the clubs by TOTAL WEIGHT, which necessitated adding weight under the butt, down the shaft AND in the head. I found these clubs way too heavy, mainly because of my 102 g grip.

[Started2k3]

... Mine are all matched at 301 cpm's ...

Are the frequency profiles matched also? Not just butt frequency, so the frequency measurement at 21" is the same for all your clubs (irons)?

[BC MIST]

Are the frequency profiles matched also? Not just butt frequency, so the frequency measurement at 21" is the same for all your clubs (irons)?

I just matched the butt frequencies. It would be a challenge to match the shafts at 21", but they could still be called Single Frequency Matched clubs?

[Started2k3]

I just matched the butt frequencies. It would be a challenge to match the shafts at 21", but they could still be called Single Frequency Matched clubs?

Is there anybody/company out there that does try to do full frequency profile matching? Or are there any theories on how this would be done (Wishon maybe)?

[jvincent]

Is there anybody/company out there that does try to do full frequency profile matching? Or are there any theories on how this would be done (Wishon maybe)?

I haven't heard of any doing that, but it would be a royal pain to do unless you build a single length set, in which case it would be easy.

For a graduated length set the problem you run into is that head weight changes. While theoretically you could trim a set of irons so that the tip frequency is the same at 21" but that would probably make matching the butt frequency at normal playing lengths problematic, assuming it's even possible. Adding MOI into the mix makes it that much harder.

Think of it as solving a system of equations. There may be a solution for a given set of variables, but then again there may not be if you constrain it in too many ways.

[Started2k3]

I haven't heard of any doing that, but it would be a royal pain to do unless you build a single length set, in which case it would be easy.

For a graduated length set the problem you run into is that head weight changes. While theoretically you could trim a set of irons so that the tip frequency is the same at 21" but that would probably make matching the butt frequency at normal playing lengths problematic, assuming it's even possible. Adding MOI into the mix makes it that much harder.

Think of it as solving a system of equations. There may be a solution for a given set of variables, but then again there may not be if you constrain it in too many ways.

Solving systems of equations doesn't scare me. Everyday I deal with a computer model of the Canadian economy that has a system of approximately 26,000 equations. So this should be child's play.

So the real question is: Do we know all the equations? I would guess not all the equations.

If we knew all the equations, wouldn't this be the ultimate solution? Where the entire shaft (BUTT, MID, TIP sections) reacts the same accross all clubs and they are MOI matched.

[jvincent]

So the real question is: Do we know all the equations? I would guess not all the equations.

No, we don't know all the equations, especially the ones for shaft stiffness as function of length.

More importantly, what's right for one person (MOI matching) may not be right for another person (SW matching).

[Started2k3]

No, we don't know all the equations, especially the ones for shaft stiffness as function of length.

I am working on it.

What are some of the functions/relationships?
stiffness and overall length (butt trimming)
stiffness and tip trimming
stiffness and head weight
Any others?

More importantly, what's right for one person (MOI matching) may not be right for another person (SW matching).

I would suspect that SW matching would be easier to full frequency profile a set, but I am not entirely sure.

[jvincent]

What are some of the functions/relationships?
stiffness and overall length (butt trimming)
stiffness and tip trimming
stiffness and head weight
Any others?

Your questions are an example of where it starts to get messy. Right now most people's measure of stiffness is frequency which is not really a measure of true "stiffness" in the sense of resistance to force. Also, frequency changes as a function of the weight used during the measurement and the length of the clamp used so unless you do the measurements yourself, it's hard to get consistency.

In order to properly profile a shafts stiffness you'd need to use a more static measure like deflection/unit of force. This is what the NF4 does if I'm not mistaken. Once you have that you could, in theory create a set of variable length shafts that had the same stiffness profile along it length.

I would suspect that SW matching would be easier to full frequency profile a set, but I am not entirely sure.

SW matching is tremendously easy. I've played both MOI and SW matched sets (equally well or badly I might add) and I just rebuilt my irons to a D2 matched set. Took me two evenings to remove all the heads, clean, dry-fit to the correct weight, and re-assemble. I could have done it in one evening but there was stuff on TV I wanted to watch.

I play ProjectX so I didn't bother matching the frequency.

[Started2k3]

Your questions are an example of where it starts to get messy. Right now most people's measure of stiffness is frequency which is not really a measure of true "stiffness" in the sense of resistance to force.

That is very worrysome.

Also, frequency changes as a function of the weight used during the measurement and the length of the clamp used so unless you do the measurements yourself, it's hard to get consistency.
...

These are physical interations so there should be a relationship between all the different testing methods. The guy at Kaufman Enterprises has done a lot of independent research on these topics. http://csfa.com/techframe.htm

[rhh7]

Thanks so much for the link to Kaufman Enterprises. I will enjoy reading every word at this site. The members of this forum are so generous, with knowledge, advice, and links to fascinating information!

[Started2k3]

Thanks so much for the link to Kaufman Enterprises. I will enjoy reading every word at this site. The members of this forum are so generous, with knowledge, advice, and links to fascinating information!

The guy at Kaufman really does a lot of great research. Note that he goes back and updates the technotes occasionally, which makes it great for a re-read after a little while.

[Chieflongtee]

Tutelman is pretty good too. You might also want to read Jorgensen's : The physics of Golf.