Question:
We are not discussing this/these subjects from the same perspective or experience. I have no idea of the meaning of MOI (think that was term) nor have I ever owned a Freq. Machine (almost after my time). Still read but have not touched another’s club since 1993. Immediately after the 1st. article re. a spline finder a buddy and I designed a home made one and experimented w/ it. Didn’t use it much although it worked fine. I also designed a Flex Board. I read everything Ralph Maltby wrote. He published a large repair book and another pertaining only to custom fitting. Also videos. Golfsmith was an embryo. I wore out a club bending machine. Graphite shafts and sets using graphite were all over the quality control charts. I once bought 6 sets of Yamaha G. shafted woods (most expensive of any sold at that time). Several of the "S" were the most flexible and several of the "R’ the stiffest. I made clubs thru the Featherweight era(Ray Floyd), B-8 swingweights, light flexible shafts. Lots of people liked them and actually hit them farther. (but wild) Even replaced a lot of screw out shafts. Most drivers weighed 13 or more ounces. I watched the birth of lightweight steel shafts( after TT lite), the Ping woods, Callaway, Taylormade and Founders , lots of caved in faces, especially w/ clones. I watched idiots design machines and measuring devices to custom fit clubs and charge enormous prices for crappy irons set at 5* upright. The progress made re. quality control of G. shafts, metal wood supports, stronger metals have allowed the significant reduction in overall weight and increase in CC size. Thus the rendering obsolete of many fine old courses. Swingweight has become almost a moot point. Just something to talk about. Every club will measure something, hopefully around D-0. I knew a lot of good players who lengthened their clubs and added lead tape under the grip to achieve the same feel, swingweight as before. The extra length and change in overall weight hindered most, helped few. Many golfers need at least 3* of torque. I repaired for 7 facilities and sold assembled clubs to 3 or 4 for at least 15 years. Replaced inserts (custom) even refinished for a while but shortly thereafter limited that to old persimmon ( most after the 60’s was not so great) for display. How many thousand, I have no idea but always bought iron heads by the cases and often sold 30 metal woods at a time. Bought Louisville wood heads 50 at a time. Most of my custom work was for single diget handicappers and most had a pretty good idea what they wanted.I did routinely cut shafts to make R, S and in between. .All this while playing 5 or 6 times a week! If you take several identical clubs and equip them w/ different size, O D, grips, maintain same swingweight and hand them to friends, customers, you’ll change your mind about telling difference in swingweight. They can’t tell the difference just as if you place 2 identical drivers on the floor, heel to face, shafts parallel, in front of you. The front one will appear 2 or more degrees closed than the rear one, switch. Golfers are nuts, many suffer I Q drops while on the course and illogically look for ways to improve their swings by improving their equipment. BTW. Would like to test your swingweight guesses w/o your knowing in advance or change a few shaftbands.
– Hide quoted text — Show quoted text – Overall weight of a club is much more important than swingweight. Most golfers, 99.9%, pros included, can’t tell the difference in 2 or 3 swingweights unless you get below C-9 or above D-4. Well, Wally, I would not agree with that. Swingweight allows you to feel the clubhead at the end of the shaft. Overall weight is important, but so is swingweight. It’s not an either-or proposition. I can feel 2 swingweight points. The conventional wisdom is that almost nobody can feel a 1 SW point difference but at 2 points that difference is apparent to many. Especially pros. Swingweight can influence the shaft flex considerably (also torque) but is over rated as a serious consideration when worrying about the characteristics of a club. I would disagree with that. Among other things, it can affect how the flex feels, and feel is a very important variable in fitting. But it’s not going to change the effective flex of a shaft all that much. Adding 2 grams of weight in a clubhead will increase the swingweight 1 point. That same weight will decrease the frequency by about 1cpm. It’s generally accepted that a 1-flex-grade difference between shafts is equivalent to about 10cpm, so you’d need a 5-point change in Swingweight to affect flex about 1/2 flex grade. I assume that to affect shaft flex "considerably" would mean something along the lines of 1/2 flex grade. Many golfers actually hit all their clubs, D-0’s included, farther and straighter when they choke down an inch. How many times have you choked down a P.W. for a shot requiring about 90% of the distance you normally hit your pitching wedge, then hit in over the green. I never have. I agree that for some people, their clubs are too long. Choking down never gets me more distance, however. Maybe my clubs are fit well to me? :) Mike Mike Dalecki I do not patronize spammers. Help keep RSG clean! GCA Accredited Clubmaker. Web Site: http://www.dalecki.net/clubdoctor/ RSG-Wisconsin 2002 Report/Pics: http://dalecki.net/rsgwis2002/part1.html RSG Roll Call: http://rec-sport-golf.com/members/?rollcall=daleckim
Response:
The progress made re. quality control of G. shafts, metal wood supports, stronger metals have allowed the significant reduction in overall weight and increase in CC size. Thus the rendering obsolete of many fine old courses.
I agree with your general sentiment, and I’m against these equipment and rule changes. But, I don’t think old courses are rendered obsolete for most amateur – just the pros. One of the worst aspects of these equipment changes with regard to length is that the pros tend to benefit more than amateurs, which is just the opposite effect intended. Swingweight has become almost a moot point. Just something to talk about. Every club will measure something, hopefully around D-0.
I don’t follow your logic here, if there is any. Of course every club will have a measurable swingweight. Why do you say "hopefully around D-0". If you want it to be there, then you just contradicted yourself – it’s not a moot point. I knew a lot of good players who lengthened their clubs and added lead tape under the grip to achieve the same feel, swingweight as before.
As we’ve said before, this is not a very good way to mess with swingweight.
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Sure is nice to hear from the Knowledge Police or are you just a NIGYYSOB player!?
Uh, yeah, whatever.
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Founders Club, the forerunner of Taylormade, I think, used brass cylinders(looked almost like a spent .22 cal) w/ a ridge at one end. It fit into the small end of shaft w/ a small hole to let air out during assembly, up the butt. Evidently there were many lengths and they dry weighted and picked out the disired wt. during assembly. Many club makers used powdered lead inserted into the butt end then sealed, kept there by a small cork rodded down butt end. Some manufacturers would change swingweights as much a 5 points this way. Really a heavy hosel! I think the 1st. graphite shaft was made by Aldila. can’t remember but I do remember the 1st. ones I hit. Of course they were in Persimmon heads and the manufacturer, can’t remember their name either, claimed to have 15 different flexes. We had about 8 of the flexes (1-15 I think) from maybe a 3 thru 13. Their beauty was outdone only by their unpredictability. You could tell if one was too limber but it ended there. I suspect some shafts may have had 12* of torque. One time you hit 25 yards farther than any drive you’d ever hit however it might be 2 fairways over, left or right. None were predictable but imagine they sold many.
– Hide quoted text — Show quoted text – Well after reading post and websites, I have made two test clubs. It has been a fun project to put together but now have a questions about swingwieghts. Before I built them I downloaded Kenny Stultz’s software from the rec.sport.golf and punched in the numbers to determine if i needed to add any weight. The numbers came up close to what i was looking for. After building them I balanced weighed them on my +-1gm kitchen scales and used the web site http://www.leaderboard.com/SWINGWEIGHT to see what the final swingweights were. The results were very different. My to test clubs are: Club #1, Acer XDS2 with Harrison Pro steel shaft and Kelmac grip. Target swingweight was D1 and the software said i was close to that. Final swingweight was D6.5. Club #2 Turbo Power Steel Plus III XL-6 with Harrison Lite steel shaft and Lampkin grip. Target SW was D2 and the software said I was close to that without adding weight. Final SW as D4. How accurate/inaccurate are my pre and post measuring methods? Is there any way to prevent this when I make my full set of clubs? Is there any way to correct the clubs I have built? Should I add weight to the butt? Any advice/suggestions/comments/reprimands would be great thanks. I am heading out to the range before they close to actually hit them. Todd.
Response:
Sure is nice to hear from the Knowledge Police or are you just a NIGYYSOB player!?
– Hide quoted text — Show quoted text – Overall weight of a club is much more important than swingweight. Most golfers, 99.9%, pros included, can’t tell the difference in 2 or 3 swingweights unless you get below C-9 or above D-4. That makes no sense at all. Swingweight can influence the shaft flex considerably (also torque)… Not necessarily. If you want the club to feel heavy reduce the O.D. of the grip. An oversize grip makes a club feel light. Ever notice how heavy some ladies clubs feel, yet they may be C-4’s! You know enough to be dangerous, but you’re missing a lot of fundamentals here. You can’t buy a golf swing but you can self fit your current clubs to greatly improve your scores. 1. Most people play with clubs that are too long, especially woods. 2. Mark the centers of your irons, place a piece of masking tape across the sole of each. What does this have to do with swingweight? No one is debating the value of proper club fitting. To be a player you must know exactly how far you carry each iron. Shocking.
Response:
Overall weight of a club is much more important than swingweight. Most golfers, 99.9%, pros included, can’t tell the difference in 2 or 3 swingweights unless you get below C-9 or above D-4.
That makes no sense at all. Swingweight can influence the shaft flex considerably (also torque)…
Not necessarily. If you want the club to feel heavy reduce the O.D. of the grip. An oversize grip makes a club feel light. Ever notice how heavy some ladies clubs feel, yet they may be C-4’s!
You know enough to be dangerous, but you’re missing a lot of fundamentals here. You can’t buy a golf swing but you can self fit your current clubs to greatly improve your scores. 1. Most people play with clubs that are too long, especially woods. 2. Mark the centers of your irons, place a piece of masking tape across the sole of each.
What does this have to do with swingweight? No one is debating the value of proper club fitting. To be a player you must know exactly how far you carry each iron.
Shocking.
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I have a digital scale for measuring food. It measures in the grams and is suppose to be accurate.
Todd, I used one of those the first time I tried this stuff, and later, when comparing weights on the food scale with what I got on my swingweight scale, found considerable difference. Then, Mike D. told me about stacks of quarters (I don’t recall right now, but a certain number of quarters weighs XX grams), and weighed those on the food scale, and … no weigh! Mike, please fill in the correct numbers/equivalents. Swingweight scales are not that expensive — check out Golfworks’ economy model. Peter
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Overall weight of a club is much more important than swingweight. Most golfers, 99.9%, pros included, can’t tell the difference in 2 or 3 swingweights unless you get below C-9 or above D-4.
Well, Wally, I would not agree with that. Swingweight allows you to feel the clubhead at the end of the shaft. Overall weight is important, but so is swingweight. It’s not an either-or proposition. I can feel 2 swingweight points. The conventional wisdom is that almost nobody can feel a 1 SW point difference but at 2 points that difference is apparent to many. Especially pros. Swingweight can influence the shaft flex considerably (also torque) but is over rated as a serious consideration when worrying about the characteristics of a club.
I would disagree with that. Among other things, it can affect how the flex feels, and feel is a very important variable in fitting. But it’s not going to change the effective flex of a shaft all that much. Adding 2 grams of weight in a clubhead will increase the swingweight 1 point. That same weight will decrease the frequency by about 1cpm. It’s generally accepted that a 1-flex-grade difference between shafts is equivalent to about 10cpm, so you’d need a 5-point change in Swingweight to affect flex about 1/2 flex grade. I assume that to affect shaft flex "considerably" would mean something along the lines of 1/2 flex grade. Many golfers actually hit all their clubs, D-0’s included, farther and straighter when they choke down an inch. How many times have you choked down a P.W. for a shot requiring about 90% of the distance you normally hit your pitching wedge, then hit in over the green.
I never have. I agree that for some people, their clubs are too long. Choking down never gets me more distance, however. Maybe my clubs are fit well to me? :) Mike Mike Dalecki I do not patronize spammers. Help keep RSG clean! GCA Accredited Clubmaker. Web Site: http://www.dalecki.net/clubdoctor/ RSG-Wisconsin 2002 Report/Pics: http://dalecki.net/rsgwis2002/part1.html RSG Roll Call: http://rec-sport-golf.com/members/?rollcall=daleckim
Response:
Overall weight of a club is much more important than swingweight. Most golfers, 99.9%, pros included, can’t tell the difference in 2 or 3 swingweights unless you get below C-9 or above D-4. Swingweight can influence the shaft flex considerably (also torque) but is over rated as a serious consideration when worrying about the characteristics of a club. Many golfers actually hit all their clubs, D-0’s included, farther and straighter when they choke down an inch. How many times have you choked down a P.W. for a shot requiring about 90% of the distance you normally hit your pitching wedge, then hit in over the green. If you want the club to feel heavy reduce the O.D. of the grip. An oversize grip makes a club feel light. Ever notice how heavy some ladies clubs feel, yet they may be C-4’s! You can’t buy a golf swing but you can self fit your current clubs to greatly improve your scores. 1. Most people play with clubs that are too long, especially woods. 2. Mark the centers of your irons, place a piece of masking tape across the sole of each. In street shoes hit several balls off a piece of plywood, until you know by the tear in the tape exactly where the sole meets the wood. Adjust 1* for each 1/4 inch to have clubs w/ the proper lie. You should have about 4* difference in loft of your irons however if you normally hit most of your irons 12 yards apart in distance except say the difference between the 8 and 9 (any others also), adjust accordingly. To be a player you must know exactly how far you carry each iron. Maybe even more important than anything you can do except sink all putts inside of 6 feet is know exactly what club to use and how hard to hit it from every 100 yard marker on you home course to the exact middle of the green. ( might as well go for the 150’s also). On a calm day , calm traffic, calm wx., take a cart, 15 balls, a P.W. and S.W. and spend a few hours . S.W. is good for 100 yards. At Houston Lake CC in Perry ,Ga. where I used to play, I could hit S.W. over a few greens from the 100 yd. marker and could not reach several greens from 100 w/ a S.W. Believe me this resolves a lot of frustration.
– Hide quoted text — Show quoted text – Well after reading post and websites, I have made two test clubs. It has been a fun project to put together but now have a questions about swingwieghts. Before I built them I downloaded Kenny Stultz’s software from the rec.sport.golf and punched in the numbers to determine if i needed to add any weight. The numbers came up close to what i was looking for. After building them I balanced weighed them on my +-1gm kitchen scales and used the web site http://www.leaderboard.com/SWINGWEIGHT to see what the final swingweights were. The results were very different. My to test clubs are: Club #1, Acer XDS2 with Harrison Pro steel shaft and Kelmac grip. Target swingweight was D1 and the software said i was close to that. Final swingweight was D6.5. Club #2 Turbo Power Steel Plus III XL-6 with Harrison Lite steel shaft and Lampkin grip. Target SW was D2 and the software said I was close to that without adding weight. Final SW as D4. How accurate/inaccurate are my pre and post measuring methods? Is there any way to prevent this when I make my full set of clubs? Is there any way to correct the clubs I have built? Should I add weight to the butt? Any advice/suggestions/comments/reprimands would be great thanks. I am heading out to the range before they close to actually hit them. Todd.
Response:
<snip From your second post of possible solutions would the most realistic options for me be to shorten the length down to 37.75 and drop to a lighter shaft? I bought an extra Harrison Lite shaft and will try it out.
Both are reasonable. You have the software which will allow you to play around with different options, which is the whole idea, actually. :) It’s easier to affect swingweight quickly by shortening the club. However, remember that one point to custom clubmaking is to fit someone, and part of that fitting equation is the length of the club. Length also relates to the effective lie angle; clubs that are too long will put the toe of the club too much into the air, giving it an effectively upright lie angle. [I say effectively because the actual measured lie angle doesn't change, but for every 1/2" in clublength increase, you create an effectively 1* more upright playing condition.] Next time I will also pay more attention to the lengths in the software and when I cut.
Everybody goofs up something when they start out. You’re asking the right questions, and if you’re at the level of modeling for swingweight, then you’re actually pretty far along. I won’t tell you the mistakes I made when starting out. :) If I were to MOI match as opposed to swingweight match would the process of just playing with the lengths and the weights be the same as with swing weighting?
It is, at least theoretically. However, you’ll find that it is very difficult to build a set of MOI-matched irons out of standard components because MOI-matching will result in an ascending swingweight as you move from long to short irons. You’re talking about, oh, 6 or 7 swingweight points. If you start your 3-iron at, say, D2, then your 9 iron will end up around D8. Too heavy for most people. To make mine–and keep them at standard lengths–I asked KZG to hand-pick the 3-4-5 iron heads, and get them at the light end of the tolerance range. I then also drilled out some weight from inside the hosel, to make them light enough. IIRC, I modelled my irons on a 7-iron w/ a swingweight of D2, because I like how that feels. My 3-iron is about a C8 (I don’t have my notes handy, but that’s about right), and they go up from there. You’ll see, if you use Kenny’s software, that you can’t get a 3-iron to SW at C8 if you use standard-weight components at standard lengths, without losing some weight in the clubhead. And BTW, I hit my 3 and 4 irons better than I ever have hit long irons before. They feel unbelievably good–and the act of swinging them feels just like swinging that 7-iron. The other method is to use components that give you a 7-gram progression in weights of the heads, weight-sorted shafts with the lightest in the long irons, and build a set with some sort of standard SW in mind–BUT, to vary the lengths not by 1/2", but by either .4" or .375". If you play w/ Kenny’s SW software, you’ll find that varying the lengths like this will produce very closely matched MOIs. And varying the lengths is far easier than how I built my irons. The way you do it is to pick out your favorite club–when I built an earlier set MOI-matched, I varied the lengths from the 7-iron. In other words, the 7-iron was standard length, and the others varied by .4" from that. The practical effect is to make your short irons a bit longer than normal, and the long irons a tad shorter than normal. W/ the 7-iron at, say, 36.5", the 8-iron would be 36.1", the nine iron at 35.7", the 6-iron at 36.9", and so on. Is there a target MOI?
It’s based on what club feels the best for you. Going to be different for different people. Or should I just stick to the simpler swingweight for my first project?
Stick w/ swingweight. I have mixed feelings about MOI-matching for people who aren’t adventurous, or don’t understand what, exactly, it’ll do for you. You need to play MOI-matched irons from pretty much the same place in the stance–the place you’d play your reference iron. They work very well for me, but normally people are used to using ball location that varies, with the ball forward for long irons, back toward the middle of the stance for short irons. There’s nothing wrong w/ Swingweight matching, so long as you find the right ball location to play each shot from–which everyone has to do anyway. [As a side note, something that is on my list of things to explore, is my nascent belief that the reason people don't like how some clubs feel is that the swingweight is wrong *for where they play the ball in their stance*. And if they simply moved the ball location to something more appropriate, they could hit most any club within the range of normal swingweights. I say this because different clubs w/ same swingweight in a set have different MOIs, and the name of the game w/ clubs that have the same MOI is to hit them from the same place in the stance. But this is something I'm exploring. Happy to hear from anyone who wants to offer opinions on this.] For starters, stay w/ swingweight, and then work toward other ways of building clubs. (Wow, this dark side is powerful, isn’t it? 
BTW the Acer XDS 2 is an Calloway X-14 look alike and the Steel Plus III is a Big Bertha look alike. Thank you for your help and for the help I will be asking for over the next days and weeks.
Good luck! Mike Mike Dalecki I do not patronize spammers. Help keep RSG clean! GCA Accredited Clubmaker. Web Site: http://www.dalecki.net/clubdoctor/ RSG-Wisconsin 2002 Report/Pics: http://dalecki.net/rsgwis2002/part1.html RSG Roll Call: http://rec-sport-golf.com/members/?rollcall=daleckim
Response:
First, thank you Mike and Jeff for responding so quickly and to Kenny for making the software availible. Ok here goes. First, the balance point of the shaft affects the swingweight. Did you include a balance point?
I balanced the club on the scale, took the reading, and then put a small mark at the balance point on the shaft to measure. Second, how are you weighing your parts? How accurate is your scale? If you’re off by just a couple grams here, or a couple there, you can miss by a couple of swingweight points (two grams in a clubhead is worth about a swingweight point). Do you have an accurate way to measure weight, such as a digital scale? Have you validated whatever scale you do have?
I have a digital scale for measuring food. It measures in the grams and is suppose to be accurate. So after reading your post, I took the 4, 6, 8gram lead tip weights that I had ordered from Golfsmith and put each one on the scale. The scale accurately weighed each lead weight in all three bags. Third, were the lie angles unusual? The flatter the lie angle, everything else being the same, the heavier the swingweight, as flattening the lie moves the head weight a bit further away from the grip end of the club.
I don’t think so, but I’ll try to compare specs on this head and others to see if it is unusual. Fourth, there’s always a little rounding error. If you have rounding errors that underestimate the true weights of the shaft and head, but overestimates the grip weight, that might get you a swingweight point.
I measured each component with the above mentioned scale in grams. Fifth, did you have the uncut lengths of the shafts correct?
Yes. Sixth, when the target software says you are "close" to D1, how close?
It was D0.9 Seventh, are you measuring length the same way Kenny is? There are about a half-dozen different ways to determine club length. If your measuring method produces a longer club than Kenny would produce, then that would account for some of the difference.
This is where the problem was/is. After looking back at the software for final club length I noticed that the final club length for a 5 iron was defaulted at 37.5in. I had failed to check this number because I assumed it as a standard number. I assembled the club referencing Golfsmith’s 5 iron of 38in. This put the SW up to D4.3. I rechecked the length of my club and depending on the angle it is .25 to .5in long. Putting those numbers into the software gives me SWs of D5.9 to D7.6. Which is right about where my numbers came out on the final product. It’s a good idea, usually, to "dry-fit" the components and see what your resulting swingweight is going to be. You can measure for length, cut the shaft to the target length, and then with a bit of patience balance the butt-end of the shaft together with the grip on the swingweight scale.
I will do that from now on. After I cut the grip off this shaft I will have old grip to dry fit with. From your second post of possible solutions would the most realistic options for me be to shorten the length down to 37.75 and drop to a lighter shaft? I bought an extra Harrison Lite shaft and will try it out. Next time I will also pay more attention to the lengths in the software and when I cut. I will take these lessons I have learned and apply them when I rebuild these clubs and then see how they work. If I were to MOI match as opposed to swingweight match would the process of just playing with the lengths and the weights be the same as with swing weighting? Is there a target MOI? Or should I just stick to the simpler swingweight for my first project? BTW the Acer XDS 2 is an Calloway X-14 look alike and the Steel Plus III is a Big Bertha look alike. Thank you for your help and for the help I will be asking for over the next days and weeks. Todd
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<snip Is there any way to correct the clubs I have built? Should I add weight to the butt?
As JeffC notes, don’t fool w/ adding weight to the butt end. All it does is fool the swingweight scale, but it doesn’t make the club less "head heavy." There are only 3 realistic ways to reduce the swingweight in a club: Lighter shaft, shorter length, and less weight in the head. You might, depending on the hosel design, be able to drill out 2-5 grams of weight from the hosel. That will allow you to reduce the swingweight in the most cosmetically-acceptable fashion. You can also try, if you’re feeling brave, to grind some from the back of the clubhead, in such a way as to retain the center of gravity/balance of the clubhead. This isn’t a particularly good approach, esp. if you’re trying to create a prototype for a set. I’ve thought about this some more and I think there’s a piece here we don’t know. When I used Kenny’s software to model my own clubs (MOI-matched them rather than swingweight matching them), the software tended to *over* predict the swingweight, not under-predict it as in your case. I concluded, after talking to Kenny about it, that the size and design of a clubhead is going to affect how much it "weighs" on the end of a shaft. Larger heads will have the center of gravity further away from the butt end of the shaft. Mine are somewhat smaller, a more traditional size. I am not familiar with the clubhead designs you’re using, but are they oversized heads? It’s possible that they simply "stick out" too far, and that’s where you’re getting the difference between predicted and actual. The lesson in this is that it’s best to check and see how good or bad your predictions are, by dry-fitting the components for one club and seeing how close they come. I have an old grip that I’ve split down the side, to which I’ve attached one layer of grip tape on the outside. I can slip this over the butt end of a shaft cut to length, stick the tip-trimmed tip into the head, and check to see what the swingweight is actually going to be. It’s the only way to be sure, esp. with the variety of weird designs that exist today. Mike Mike Dalecki I do not patronize spammers. Help keep RSG clean! GCA Accredited Clubmaker. Web Site: http://www.dalecki.net/clubdoctor/ RSG-Wisconsin 2002 Report/Pics: http://dalecki.net/rsgwis2002/part1.html RSG Roll Call: http://rec-sport-golf.com/members/?rollcall=daleckim
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Is there any way to correct the clubs I have built? Should I add weight to the butt?
I would never add weight to the butt to change swingweight. I don’t think swingweight was "designed" to do things that way. I’d keep the butt standard in all respects, unless you know in advance you need a certain grip, or you have to extend the butt end of the club, and you know what it will do to the end result. Otherwise, I’d mess with the head only.
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- Hide quoted text — Show quoted text – Well after reading post and websites, I have made two test clubs. It has been a fun project to put together but now have a questions about swingwieghts. Before I built them I downloaded Kenny Stultz’s software from the rec.sport.golf and punched in the numbers to determine if i needed to add any weight. The numbers came up close to what i was looking for. After building them I balanced weighed them on my +-1gm kitchen scales and used the web site http://www.leaderboard.com/SWINGWEIGHT to see what the final swingweights were. The results were very different. My to test clubs are: Club #1, Acer XDS2 with Harrison Pro steel shaft and Kelmac grip. Target swingweight was D1 and the software said i was close to that. Final swingweight was D6.5. Club #2 Turbo Power Steel Plus III XL-6 with Harrison Lite steel shaft and Lampkin grip. Target SW was D2 and the software said I was close to that without adding weight. Final SW as D4. How accurate/inaccurate are my pre and post measuring methods? Is there any way to prevent this when I make my full set of clubs? Is there any way to correct the clubs I have built? Should I add weight to the butt? Any advice/suggestions/comments/reprimands would be great thanks. I am heading out to the range before they close to actually hit them. Todd.
Todd, here are several things which might affect your results, in no particular order: First, the balance point of the shaft affects the swingweight. Did you include a balance point? Second, how are you weighing your parts? How accurate is your scale? If you’re off by just a couple grams here, or a couple there, you can miss by a couple of swingweight points (two grams in a clubhead is worth about a swingweight point). Do you have an accurate way to measure weight, such as a digital scale? Have you validated whatever scale you do have? Third, were the lie angles unusual? The flatter the lie angle, everything else being the same, the heavier the swingweight, as flattening the lie moves the head weight a bit further away from the grip end of the club. Fourth, there’s always a little rounding error. If you have rounding errors that underestimate the true weights of the shaft and head, but overestimates the grip weight, that might get you a swingweight point. Fifth, did you have the uncut lengths of the shafts correct? Sixth, when the target software says you are "close" to D1, how close? Seventh, are you measuring length the same way Kenny is? There are about a half-dozen different ways to determine club length. If your measuring method produces a longer club than Kenny would produce, then that would account for some of the difference. It’s a good idea, usually, to "dry-fit" the components and see what your resulting swingweight is going to be. You can measure for length, cut the shaft to the target length, and then with a bit of patience balance the butt-end of the shaft together with the grip on the swingweight scale. I think it’s an extreme miss to predict a "D1" and get a "D6.5". Something is wrong with that–as you already have figured out. You’ll have to double-check your weights and lengths to be sure you have it the same way Kenny’s program would expect it. Good luck! Mike Mike Dalecki I do not patronize spammers. Help keep RSG clean! GCA Accredited Clubmaker. Web Site: http://www.dalecki.net/clubdoctor/ RSG-Wisconsin 2002 Report/Pics: http://dalecki.net/rsgwis2002/part1.html RSG Roll Call: http://rec-sport-golf.com/members/?rollcall=daleckim
Response:
Well after reading post and websites, I have made two test clubs. It has been a fun project to put together but now have a questions about swingwieghts. Before I built them I downloaded Kenny Stultz’s software from the rec.sport.golf and punched in the numbers to determine if i needed to add any weight. The numbers came up close to what i was looking for. After building them I balanced weighed them on my +-1gm kitchen scales and used the web site http://www.leaderboard.com/SWINGWEIGHT to see what the final swingweights were. The results were very different. My to test clubs are: Club #1, Acer XDS2 with Harrison Pro steel shaft and Kelmac grip. Target swingweight was D1 and the software said i was close to that. Final swingweight was D6.5. Club #2 Turbo Power Steel Plus III XL-6 with Harrison Lite steel shaft and Lampkin grip. Target SW was D2 and the software said I was close to that without adding weight. Final SW as D4. How accurate/inaccurate are my pre and post measuring methods? Is there any way to prevent this when I make my full set of clubs? Is there any way to correct the clubs I have built? Should I add weight to the butt? Any advice/suggestions/comments/reprimands would be great thanks. I am heading out to the range before they close to actually hit them. Todd.