ShopTalk: SRVII 12*
I picked up a SRVII 12* and put it together on a Rifle 5.5 shaft, no tip-trimming, spined at 12oclock. Using the plug that came with the SRVII, shaft-insertion depth ended up around 1.5 or so (didn't measure). Will butt-trim to get the SW around D2-3. Hopefully will hit it tomorrow morning in comparison to my Integra 400 9* on a DGS300 and steel XDS2+ on a TTLite XL between R/S. I also hope my swing is consistent enough to make a meaningful comparison, but I'm confident that that SRVII will be significantly straighter and more consistent than the Integra 400 which is currently in the bag. -Dave
Re: ShopTalk: Swingspeed vs. trampoline effect
Dave and Tom: So it looks like we have a bit of differing opinions here. Dave, you would suggest that the COR, for a given clubhead/ball combo, is close to a constant for all clubhead speeds. Tom seems to indicate that the COR is non linear enough to make a significant difference. It seems a lot of the COR would depend on the construction of the ball, maybe to an extent that the flexing of the face is almost irrelavant. I don't know. Interesting discussion. Max... Tom Wishon wrote: Guys: Been reading your comments on spring face with interest. Lots and lots of things to comment on but don't want to make this too long, so I will try to hit the high points about which I think mine and my engineering consultant's knowledge is pretty solid. 1. Perhaps the worst piece of misinformation in all this is the actual term trampoline effect, for the reason it gives you the mental image of the face acting like a 'slingshot'. What happens to increase ball velocity off a so-called spring face is that when the head is allowed to lose more energy by the face deflecting more, then the ball loses less energy - and then can leave the face at a higher velocity relative to the head's velocity. If you have less face deflection for the speed of the head, then the ball is deforming (squashing) more, the ball then is losing more energy and it cannot leave the face as fast. 2. Remember - it is the BALL that is the source of almost all of the energy loss at impact. The greater the squashing of the ball, the more the ball energy loss. This matter of loss VS ball squashing is NOT linear. If it were, then twice the squashing of the ball would produce twice the energy loss. What happens is as the deformation of the ball doubles, the losses more than double. 3. Yes, it was me and my engineer who came up with the idea of different swing speed limits for the different head designs when I was with Golfsmith. Reasoning for this was based on #1 and 2 above. Higher swing speeds cause more face deflection for any particular face thickness. No matter what, a slower swing speed will deflect a face less. And the less the face deflection, the more the ball loses energy for that particular golfer. If you make ONE face thickness to fit all golfers, the more the golfer's swing speed decreases from the highest swing speed the face is built to withstand, the less ball velocity to swing speed improvement will be realized. To maximize the potential for the slower swinger, you have to reduce the face thickness to allow their slower swing to deflect the face more - but the downside is if that club is used by a golfer with a much higher swing speed, they will over-flex the face past its stress limit and cause permanent damage. Hence the reason for the WARNING stickers on the faces of those drivers we designed for GS. 4. If you plot a curve of the COR VS the Spring Rate of the face, the COR starts out at a low value with a face that is very flexible and increases as the face assumes a higher spring rate until the peak is reached at about a 0.86 COR value. Continued increase of the spring rate results in a LOWER COR until the idea levels out to a point where the face would be totally rigid, at a COR of about 0.76. 5. The keys to higher COR drivers that can maximize the ratio of swing speed to ball speed, are, a) larger faces that are more TALL than wide. Our studies indicate that face height is 3 times more influential on the ability of the face to deflect than face width. B) face materials with a high yield strength + low modulus of elasticity AT THE SAME TIME TOGETHER. This is why Beta Ti alloys are so good to use. But do not forget, super high strength steels that allow less face thickness than the beta ti alloys are good too - we were able to make an Aermet face driver that had the same 0.845 COR as the Beta Ti back in 2000. Their only drawback is their higher density - as the face area increases the weight does too - which puts limits on how large you can make a steel head and still have the desired headweight for swingweighting purposes. 6. It is possible for a slow swinger to get more ball velocity from a thin face big head than if that same slow swinger was using a much thicker faced driver. But do not even think they are getting close to what the faster swinger is getting in terms of face deflection/ball energy loss reduction. Use common sense - a 50 mph swing is still going to deflect a thin face more than it will a thick face. It won't get the MOST out of it like the 100mph swing will, but it will still get some improvement over what happens with the thicker face. TOM W
Re: ShopTalk: SRVII 12*
I think you'll like it, if the head is the only variable in the equation. But it isn't; you're also looking at different shafts. I have a Bang SRV-II 10* on an SK Fiber Pure Energy shaft. It was in my bag for the past month. I'd have to give it a very good grade, though I'm about to swap it out for the driver it replaced -- after a range session today. That driver is an Integra IV 10* on an SK Fiber Tour Trac 80. Here's my story on it: * The head itself is well-made, and sports a good finish. It also seems to hold its finish well. * Compared to the Integra IV and the UC Big Titanium (both similar in shape to the Ping TiSi), the SRV-II is taller in the face. I think this makes it a lot less sensitive to teeing height. I got the designed-in trajectory with just about any decent hit. * I got plenty of distance with the SRV. Even shots that felt a little like misses went further than I expected. I keep thinking back to a match I played in the first weekend I used it. On the last hole (#1 hcp, long par 4), it didn't feel quite solid, but it finished in the fairway, having airmailed the bunker that caught the other drives in my foursome. All this is consistent with Dan Neubecker's report of two months ago. The SRV is long and forgiving. So why will it not be in my bag tomorrow? Well, as TFlan is fond of reminding us, a good club doesn't make a good golfer. As the club gets longer, my swing tends to get more outside-in. A forgiving head may mask off-center hits, but there is no way it can mask a glancing blow. Too many of my drives with this club are long but in the trees on the right (face square to target line = slice) or the left (face square to path of clubhead = pull). The other driver is shorter in length. I don't think it hits the ball as far, but I'm seldom as far off-line either. (Penick - The woods are full of long hitters.) In this morning range session, I focused on clubhead path. I could manage it better with the shorter driver, so I'll see how it works on the course. The difference is not much: 44 vs 45-1/4. That's worth about a dozen grams of head weight. If the switch back to the shorter driver works, I may try to shorten the SRV and see what happens. I expect I'll like the result. Cheers! DaveT - Original Message - From: David Rees [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, July 02, 2002 6:07 PM Subject: ShopTalk: SRVII 12* I picked up a SRVII 12* and put it together on a Rifle 5.5 shaft, no tip-trimming, spined at 12oclock. Using the plug that came with the SRVII, shaft-insertion depth ended up around 1.5 or so (didn't measure). Will butt-trim to get the SW around D2-3. Hopefully will hit it tomorrow morning in comparison to my Integra 400 9* on a DGS300 and steel XDS2+ on a TTLite XL between R/S. I also hope my swing is consistent enough to make a meaningful comparison, but I'm confident that that SRVII will be significantly straighter and more consistent than the Integra 400 which is currently in the bag. -Dave
Re: ShopTalk: golf ball compression
Guys, there is a booklet that comes out every years called "Golf Balls". It compares every brand / compression of golf ball on the market at 80MPH / 90MPH / 100mph plus in the last issue thatI got they also compared drivers hitting just one type/style/name brand ball. The driver werea Titkest 975, a GBB, a Callaway ERC and a NIKE. The longest ball, @ a 90MPH Swing Speedby 6", was a Topflight. second was a Lady Precept @ 80MPH. The over all range of all balls at all swing speeds,ifI remember correctly, was about 25 yards. Of course this test did not use the newer lower compression balls. RK Manufacturer's of World Class Golf Club Repair Equipment [EMAIL PROTECTED] ---Original Message--- From: [EMAIL PROTECTED] Date: Tuesday, July 02, 2002 05:29:42 PM To: [EMAIL PROTECTED] Subject: Re: ShopTalk: golf ball compression Hi;Even longer ago than the GD study, perhaps in the mid-seventies, anAustralian University posted test results on golf balls. They tested 100,90, and 80 compression balls with a robot device much like the one USGAuses. The robot was set to make contact at something like 100 mph. Ballswere all brand new, all from different companies. The conclusion drawn,based upon several hundred hits, was that higher compression balls wentfarther than did lower compression balls when struck at the same swingspeed.A couple of years later, a university in the mid-west, it may have been Iowaor Ohio, did the same test and got the same results. Conclusion from both ofthem? 100's went farther than 90's which went farther than 80's. However,feel is a major factor in selection a ball. Here in Central CA, where thetemperature is hovering at about 100, hard balls don't feel too bad. TopRocks feel like Noodles, and Noodles feel like pancakes. In the wintermonths with temps in the high 30's/low 40's, the Precept Lady seems to feelbest.TFlan- Original Message -From: "Scott Bershing" [EMAIL PROTECTED]To: [EMAIL PROTECTED]Sent: Tuesday, July 02, 2002 1:27 PMSubject: ShopTalk: golf ball compression All this talk of compression and trampoline effect has me curious. A few years back, Golf Digest performed a study on golf ball compressions, and the effects on distance. I don't remember the exact findings, but ifI remember correctly, the gist was that the compression had more to do with feel than distance. I think there was less than a yard difference between the same brand balls of different compression. Another thing is the recent popularity of ultra-low compression balls like the Precept Lady and Laddie, and now the Noodle. These things are like 60 compression, and people claim they are hitting them longer than anythingelse. I'm not sure how modern trampoline faces compare with each extreme, but it sure would be neat to see how ultra-high COR heads and rigid heads compare in hitting balls that range from marshmallows to rocks. Scott.
Re: ShopTalk: SRVII 12*
On Tue, Jul 02, 2002 at 06:42:05PM -0400, Dave Tutelman wrote: I think you'll like it, if the head is the only variable in the equation. But it isn't; you're also looking at different shafts. The shafts should be fairly similar, the RSSR readings for the DGS300 and the Rifle 5.5 are almost the same. I will be building the clubs to the same length, the headweight of my Integra 400 and SRV-II are both right at 199.5gms. All this is consistent with Dan Neubecker's report of two months ago. The SRV is long and forgiving. So why will it not be in my bag tomorrow? Well, as TFlan is fond of reminding us, a good club doesn't make a good golfer. As the club gets longer, my swing tends to get more outside-in. A forgiving head may mask off-center hits, but there is no way it can mask a glancing blow. Too many of my drives with this club are long but in the trees on the right (face square to target line = slice) or the left (face square to path of clubhead = pull). The other driver is shorter in length. I don't think it hits the ball as far, but I'm seldom as far off-line either. (Penick - The woods are full of long hitters.) In this morning range session, I focused on clubhead path. I could manage it better with the shorter driver, so I'll see how it works on the course. The difference is not much: 44 vs 45-1/4. That's worth about a dozen grams of head weight. If the switch back to the shorter driver works, I may try to shorten the SRV and see what happens. I expect I'll like the result. Going to a 44 steel shaft over a 45 graphite made a world of difference in accuracy. I too fight the slice, and a 45 club almost always equaled OB-right except when I really slowed down my swing and concentrated on the swing plance or aimed at the rough on the left. Of course then I'd pull the shot and I'd be in trouble there, too. ;-) I hit the 44 farther than the 45 graphite on average, but surprisingly I've hit shots just as far on both setups, most likely because of the added confidence and the fact that I'm confortable swinging harder on the shorter shaft. I expect that you'll like the SRV-II more than the Integra IV after getting the overall length of the club down the same as the other. I bet you'll still hit it just as far but keep it in play as well, too. If I get the results anything close to what Dan got with his 12* SRV-II (consistent high, straight down the middle) I'll be very happy and I'll have one Integra 400 in the closet. -Dave
Re: ShopTalk: Swingspeed vs. trampoline effect
- Original Message - From: Max Dupilka [EMAIL PROTECTED] Sent: Tuesday, July 02, 2002 6:12 PM So it looks like we have a bit of differing opinions here. Dave, you would suggest that the COR, for a given clubhead/ball combo, is close to a constant for all clubhead speeds. Tom seems to indicate that the COR is non linear enough to make a significant difference. You're right about a difference of opinion. At least I think you are. You have correctly stated my position -- I said there's a little variation in COR, but not enough to matter. I also said that there is even less variation in the COR improvement due to a flexible face. I'll let Tom say for himself whether you correctly paraphrased him, but that is how I read his note. To highlight our difference, consider two of TW's statements: This matter of loss VS ball squashing is NOT linear. If it were, then twice the squashing of the ball would produce twice the energy loss. What happens is as the deformation of the ball doubles, the losses more than double. -- and -- If you make ONE face thickness to fit all golfers, the more the golfer's swing speed decreases from the highest swing speed the face is built to withstand, the less ball velocity to swing speed improvement will be realized. These don't necessarily follow. With the same face thickness, the higher swing speed will produce more deflection of BOTH face and ball. That means that the lower swing speed will experience a higher ball velocity to swing speed ratio. Now let's consider the IMPROVEMENT due to a flexible face, which I think is what TW was trying to get at. Certainly the higher clubhead speed NEEDS more improvement, because it squashes the ball more. But not only do the energy losses increase faster than proportional (that is, nonlinearly); so does the force required to do the squashing. So it's not obvious that the improvement is greater for the higher clubhead speed. I believe both TW and I believe most of the results of a paper by Alastair Cochran (Club Face Flexibility and Coefficient of Restitution, Science and Golf III, 1998). He uses a nonlinear spring for the ball, resulting in the sort of loss characteristics that Tom refers to. The reason I think Tom believes this paper is that its results agree precisely (for an undamped spring face) with his statement: 4. If you plot a curve of the COR VS the Spring Rate of the face, the COR starts out at a low value with a face that is very flexible and increases as the face assumes a higher spring rate until the peak is reached at about a 0.86 COR value. Continued increase of the spring rate results in a LOWER COR until the idea levels out to a point where the face would be totally rigid, at a COR of about 0.76. That paper is the only place I've ever seen that curve, so I suspect we're both working from that as the source. Let's see what the paper has to say about variation of clubhead speed -- because Cochran DOES look at that in his paper. It plots the curve for a lightly damped clubface, for two clubhead speeds: 30m/s and 50m/s. This corresponds to about 67mph and 112mph. * For a rigid clubface, the lower clubhead speed gives a COR of .773 and the higher a COR of .756. * For the optimum-flexibility clubface (it isn't exactly the same flexibility for the two speeds, but it's really close), the lower clubhead speed gives a COR of .828 and the higher a COR of .818. Hence my statement that the lower clubhead speed gets a somewhat better COR, because it doesn't squash the ball as much. This is true for both the rigid face and the optimum spring face. But let's look at the improvement, because I think that's what was really being asked, and what Tom answered. Going to an optimum spring-face (with the assumption of light damping) from a rigid spring face gives: * For the 112mph swinger, a COR improvement of 9.2%. * For the 67mph swinger, a COR improvement of 9.3%. Just a tiny bit better for the slow swinger, but not enough to make a difference in ANYBODY's golf game. I stand by my previous statements, unless somebody can show me an equally convincing work on the other side. Cochran's paper is out there for anybody to see and criticize. It seems a lot of the COR would depend on the construction of the ball, maybe to an extent that the flexing of the face is almost irrelavant. I don't know. It would seem. I really don't know, so I won't say anything. Cheers! DaveT Tom Wishon wrote: Guys: Been reading your comments on spring face with interest. Lots and lots of things to comment on but don't want to make this too long, so I will try to hit the high points about which I think mine and my engineering consultant's knowledge is pretty solid. 1. Perhaps the worst piece of misinformation in all this is the actual term trampoline effect, for the reason it gives you the mental image of the face acting like a 'slingshot'. What happens to increase ball velocity off a
ShopTalk: Re: [SpinetalkersForum] Not golf, computer probs
ROTFLMAO! Yeah, you're right. I'm not a computer maven but I have been running them for a long time . . . mostly PC's though. Mac'er's absolutely love them. PC'ers are mostly ambivalent, I think. The reasons I started all this, aside from the most recent crash, are that I recently purchased a digital camcorder. My PC won't run video unless I shell out more $$$ for a firewire card and software. I'd like to be able to edit and perhaps adjust my pitiful swing after reviewing movies of the lurch. Second, my eldest son, Sir Kevin of Silicon Valley, is a programmer. He's been writing code for 2 huge companies in the Bay Area for a long time. He owns 3 PC's including one of those multi-gigabyte HD/Memory/super-cooled speed burners that cost mega bucks. He just ordered the fastest Mac on the market. He says it won't even be available until the end of July. He says Pops, I'm putting my money where my mouth is. Windows is crap, DOS is crap, MS never got it right. I make my living writing code but I'm buying a $3500 Mac. So I said, what the hell do you know? I repair golf clubs. A brilliant riposte, if I do say so myself. I spent a lot of time yesterday at 3 computer stores talking with Mac guys including one who worked for Apple and another non-commission guy who simply answered questions. I also spent a lot of time using an iMac in 2 of the stores. The sales force must have been furious. All this talk about intuitivity, and so on is just so much bullshit, I think. I can run a computer whether it be a Mac or a PC. I can't approach this as would a neophyte so I asked JanFlan (She Who Must Be Obeyed) what she thought about buying a $2K computer. Her response? Go ahead but I'm keeping the PC. It took me 20 years to learn how to turn it on. I don't want to start all over. But . . . that iMac sure is cute. It looks like something from StarWars! So, based upon the couple of hours I spent with the iMac, and considering that its really cute, I guess I'm beginning to see Apple's point. I think the point is, We Can Design And Market A Really Cute, Easy To Run, Affordable Machine That Won't Crash Every Two Months. I'm getting closer. Enough of this though. We'll go back to our golf stuff. TFlan The feedback I got from users was that Mac users recommended them, PC users recommended PCs, and people who used both said they both suck. If you take the leap, please post your own experiences after a few months. -Don M
Re: ShopTalk: Not golf, computer probs - now perhaps *LINUX*
Tom, I agree with you son, Micro$oft has never gotten it right, and I suspect, never will. But he also needs to know that MAC is *not* the only alternative. Especially since he sounds like a bright individual. I would like to suggest he look into LINUX. Ignore the false lies circulated by M$ etc. about Linux. M$ is scared, *real* scared by Linux. My wife I have both switched *entirely* to Linux, and My son has too, except he is required by his school to work in M$ format. (He does this under Linux, and saves in M$ DOC or whatever is needed). Each time I introduce a family to Linux, they end up switching over, some using both, and others nearly, or completely using only Linux. This switch usually occurs after a lengthy session to remove numerous virii (viruses if you prefer), from their M$ system. Then they start by browsing, and e-mailing under Linux. Next is to simply trash Micro$oft altogether. Why use it, when pretty much anything you need, is available under Linux, - and it doesn't crash, or spy on you, - and is significantly more immune to the bugs going around these days. Linux is also affordable by anyone, - it can be downloaded free, or purchased, to get more software, and support Lots of options, plenty of support on line, - and if you buy one CD set, you can *legally* install it on as many computers as you want! (Note: there are some distributions trying to get greedy, and undermine this aspect of the GPL(General Public License). Those vendors are not likely to prevail. Many like Redhat, and Many like Mandrake. The *vastly* most popular version in our house is Mandrake Linux, currently at version 8.2. (It is essentially compatible with RedHat, so software for RedHat, will 99% of the time run in Mandrake just fine. Check it out at http://www.mandrakesoft.com Please feel free to email me off list, for any questions you might have, and I will answer them if I can, or direct you to somewhere you will get an answer. You just can't beat free.. (even though I like to purchase it once in a while, to support the company). Cheers, Jorgen [EMAIL PROTECTED] ps, - Linux also runs on MAC's :o) On Tuesday 02 July 2002 06:19 pm, you wrote: ROTFLMAO! Yeah, you're right. I'm not a computer maven but I have been running them for a long time . . . mostly PC's though. Mac'er's absolutely love them. PC'ers are mostly ambivalent, I think. The reasons I started all this, aside from the most recent crash, are that I recently purchased a digital camcorder. My PC won't run video unless I shell out more $$$ for a firewire card and software. I'd like to be able to edit and perhaps adjust my pitiful swing after reviewing movies of the lurch. Second, my eldest son, Sir Kevin of Silicon Valley, is a programmer. He's been writing code for 2 huge companies in the Bay Area for a long time. He owns 3 PC's including one of those multi-gigabyte HD/Memory/super-cooled speed burners that cost mega bucks. He just ordered the fastest Mac on the market. He says it won't even be available until the end of July. He says Pops, I'm putting my money where my mouth is. Windows is crap, DOS is crap, MS never got it right. I make my living writing code but I'm buying a $3500 Mac. So I said, what the hell do you know? I repair golf clubs. A brilliant riposte, if I do say so myself. I spent a lot of time yesterday at 3 computer stores talking with Mac guys including one who worked for Apple and another non-commission guy who simply answered questions. I also spent a lot of time using an iMac in 2 of the stores. The sales force must have been furious. All this talk about intuitivity, and so on is just so much bullshit, I think. I can run a computer whether it be a Mac or a PC. I can't approach this as would a neophyte so I asked JanFlan (She Who Must Be Obeyed) what she thought about buying a $2K computer. Her response? Go ahead but I'm keeping the PC. It took me 20 years to learn how to turn it on. I don't want to start all over. But . . . that iMac sure is cute. It looks like something from StarWars! So, based upon the couple of hours I spent with the iMac, and considering that its really cute, I guess I'm beginning to see Apple's point. I think the point is, We Can Design And Market A Really Cute, Easy To Run, Affordable Machine That Won't Crash Every Two Months. I'm getting closer. Enough of this though. We'll go back to our golf stuff. TFlan The feedback I got from users was that Mac users recommended them, PC users recommended PCs, and people who used both said they both suck. If you take the leap, please post your own experiences after a few months. -Don M
Re: ShopTalk: Time out and a new way to match shafts
Geez Bernie! We've not met but as fellow "Chicopee/Springfieldians," man . . . I hope things work out. I did the open heart thing a few years ago. It made me a better person( . . . I don't give a shit what people think ;-) Our email arguments, agreements, and discussions are most enjoyable, enlightening and ultimately pointless when compared withthis malady. Hang in pal. We're all with you. TFlan - Original Message - From: Bernie Baymiller To: Shoptalk Sent: Tuesday, July 02, 2002 6:19 PM Subject: ShopTalk: Time out and a new way to match shafts ST'ers, Won't be playing any golffor a while...had my catheter implant surgery for peritoneal dialysis last Friday...two sore holes in the abdomen and a 4" tube hanging out.Can use it in two weeks and get my strength back, I hope. Funny that the lasttwo weeks before the surgery, when I had almost no leg strength or endurance, Iplayed some ofmy bestgolf in a couple of years... a 69, 72and 73 in six rounds (with a couple of 80-somethings). But...in the meantime, I have a bunch of clubs to make for friends, so I'm certainly not bored. And...I have Dan's NF2 shaft matching machine to play with. What a neat device! So simple to use once I saw how it works. Set beam length, measure deflection per inch,figure target deflections, snap in a shaft, mark NBP, slide shaft to target deflection, mark tip and cut...viola! A perfectly matched set of shafts with your choice of alignment to boot. Did some fairway wood shafts with it today. Well, maybe that's simplified a bit, but no clamping and unclamping to find the exact frequency is needed. Just slide the shaft in the bearings until it hits the required target deflection on the dial. Much faster to useto match ashaft set than a frequency analyzer. Have two sets of iron shafts to match as soon as they arrive. Will report how they go. (There must beSOMETHING difficult about using this thing.) BernieWriteto: [EMAIL PROTECTED]
RE: ShopTalk: Time out and a new way to match shafts
Hope all goes well Bernie. Good Luck with getting your strength back. MikeWalker -Original Message-From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Bernie BaymillerSent: Tuesday, July 02, 2002 9:19 PMTo: ShoptalkSubject: ShopTalk: Time out and a new way to match shafts ST'ers, Won't be playing any golffor a while...had my catheter implant surgery for peritoneal dialysis last Friday...two sore holes in the abdomen and a 4" tube hanging out.Can use it in two weeks and get my strength back, I hope. Funny that the lasttwo weeks before the surgery, when I had almost no leg strength or endurance, Iplayed some ofmy bestgolf in a couple of years... a 69, 72and 73 in six rounds (with a couple of 80-somethings). But...in the meantime, I have a bunch of clubs to make for friends, so I'm certainly not bored. And...I have Dan's NF2 shaft matching machine to play with. What a neat device! So simple to use once I saw how it works. Set beam length, measure deflection per inch,figure target deflections, snap in a shaft, mark NBP, slide shaft to target deflection, mark tip and cut...viola! A perfectly matched set of shafts with your choice of alignment to boot. Did some fairway wood shafts with it today. Well, maybe that's simplified a bit, but no clamping and unclamping to find the exact frequency is needed. Just slide the shaft in the bearings until it hits the required target deflection on the dial. Much faster to useto match ashaft set than a frequency analyzer. Have two sets of iron shafts to match as soon as they arrive. Will report how they go. (There must beSOMETHING difficult about using this thing.) BernieWriteto: [EMAIL PROTECTED]
Re: ShopTalk: Time out and a new way to match shafts
Bernie, Take it easy; follow the doctor's orders; and heal fast. You're my inspiration on these over-length (correct-length) drivers! ;-) Fairways and Greens, Cub - Original Message - From: Bernie Baymiller To: Shoptalk Sent: Tuesday, July 02, 2002 3:19 PM Subject: ShopTalk: Time out and a new way to match shafts ST'ers, Won't be playing any golffor a while...had my catheter implant surgery for peritoneal dialysis last Friday...two sore holes in the abdomen and a 4" tube hanging out.Can use it in two weeks and get my strength back, I hope. Funny that the lasttwo weeks before the surgery, when I had almost no leg strength or endurance, Iplayed some ofmy bestgolf in a couple of years... a 69, 72and 73 in six rounds (with a couple of 80-somethings). But...in the meantime, I have a bunch of clubs to make for friends, so I'm certainly not bored. And...I have Dan's NF2 shaft matching machine to play with. What a neat device! So simple to use once I saw how it works. Set beam length, measure deflection per inch,figure target deflections, snap in a shaft, mark NBP, slide shaft to target deflection, mark tip and cut...viola! A perfectly matched set of shafts with your choice of alignment to boot. Did some fairway wood shafts with it today. Well, maybe that's simplified a bit, but no clamping and unclamping to find the exact frequency is needed. Just slide the shaft in the bearings until it hits the required target deflection on the dial. Much faster to useto match ashaft set than a frequency analyzer. Have two sets of iron shafts to match as soon as they arrive. Will report how they go. (There must beSOMETHING difficult about using this thing.) BernieWriteto: [EMAIL PROTECTED]
Re: ShopTalk: Swingspeed vs. trampoline effect
Dave: Your explanation sounds reasonable to me. I will have to have a look at that article. I haven't read the Part III book yet. My whole purpose of this question is this. If a company can make an at the legal limit COR club that can withstand a 130 mph swing speed, and the COR varies only a small amount with swing speed, then the COR for an 80 mph swing is pretty well the same as at that legal limit for that given club. So you get this club tested out by the USGA and confirm it is legal. Then you make a thinner faced club that deflects even more but is only good for low swing speeds, otherwise it breaks. This would suggest that the COR of that club is higher than the legal limit club. But you don't have to get this low swing speed club tested by the USGA. Make any sense?? Max... Dave Tutelman wrote: Followup to my previous note... - Original Message - From: Dave Tutelman [EMAIL PROTECTED] Sent: Tuesday, July 02, 2002 7:44 PM Going to an optimum spring-face (with the assumption of light damping) from a rigid spring face gives: * For the 112mph swinger, a COR improvement of 9.2%. * For the 67mph swinger, a COR improvement of 9.3%. Just a tiny bit better for the slow swinger, but not enough to make a difference in ANYBODY's golf game. Actually, it's arrogant to say there's any difference at all. I really can't read the graphs precisely enough to make that distinction. Let me just say the improvement is indistinguishable. Also... Tom Wishon wrote: 5. The keys to higher COR drivers that can maximize the ratio of swing speed to ball speed, are, a) larger faces that are more TALL than wide. Our studies indicate that face height is 3 times more influential on the ability of the face to deflect than face width. B) face materials with a high yield strength + low modulus of elasticity AT THE SAME TIME TOGETHER I'm in complete agreement. 6. It is possible for a slow swinger to get more ball velocity from a thin face big head than if that same slow swinger was using a much thicker faced driver. But do not even think they are getting close to what the faster swinger is getting in terms of face deflection/ball energy loss reduction. Use common sense - a 50 mph swing is still going to deflect a thin face more than it will a thick face. It won't get the MOST out of it like the 100mph swing will, but it will still get some improvement over what happens with the thicker face. I'm mostly in complete agreement with this statements. I certainly agree that the slow swinger will get more ball velocity from a properly flexible face than a more rigid face. Obviously, I disagree with the implication that the 100mph swing will get more out of a non-rigid face, and I think I supported that in my previous note. But, as for the parts I agree with in #5 and #6, they provide a good rationale for the Elasteel line of drivers. Cheers! DaveT
RE: ShopTalk: Putter Shaft Trimming
Hi Ted, David, Arnie: I build all my putters to Stiff XStiff range, otherwise Im afraid as Arnie pointed out you begin to run out of butt diameter at the throat of the putter grip. This we found out the expensive way with a brand-newLH Scotty Cameron Newport II Pro Platinum, which we bought for eldest son as a high school graduation gift. When we received the putter (as any good clubmaker would do) we took it apart in our attempt to make it better. Here is the data collected from this 35 inch long model (although now its 34 inches long): - Shaft wt = 103.4 grams at 32.05 inches long - Butt cpm 5 inch clamp (GS unit) = 449 cpm - Tip diameter 0.355 inch parallel (that measurement for several inches) - Distance to first step 10.5 inches - Grip weight = 71.0 grams - Head weight = 335.3 grams - Butt diameter = 0.580 inch I remember we wanted to install DG-SCX100 but didnt want to ream out hosel (see not below). This expensive putter had the cheapest looking shaft I have ever seen. Ive seen far nicer commercial iron shafts at $2.45 each. Since the distance to the first step was so long then the butt diameter needed 4 to 8 wraps of build-up tape before the GP Pro Score Cord grip was ready to be installed, otherwise the throat of the putter grip would resemble a regular grip installed on a junior shaft. Titleist in their wisdom cut most of the length off the butt and the factory Cameron grip was installed over all the shaft steps. Maybe the OEMcord grip had accounted for this since it is 71 grams in weight. The junk OEM shaft was aligned NBP down target with homemade sensicore added. Prior to reusing the OEM shaft, I took a True Temper X100 Dynamic Gold Sensicore shaft (330 cpm, 125.4 grams, 40 inches) and cut it to 32.05 inches with 5 inch tip trim (4 5/8inch to first step) it now has a weight of 100.6 grams, and 484 cpm with 5 inchbutt clamp. Since I started making clubs, I have always cut 5 inches off S300 or X100 shafts and 7 inches offof TT R/S combo shafts. At least I dont run out of butt diameter to put the grip on without a ton of masking tape, and nobody has complained about the feel being overly stiff. I didn't know this at the time but the Cameron putter had a non-standard tip diameter. Would of been nicer to throw out the junk shaft and rebuild with a better shaft. After this whole exercise, he still loves his Harvey Penick Riverside (Newport style) now discontinued. His old putter still favours his putting stroke. So much for progress. He will probably sell the left hand Newport II Pro Platinum on e-bay. His email is [EMAIL PROTECTED] He also tried out 4 new drivers and he loves the KZG RBT/325 (8*) that will stay in his bag for a long time. Slightly longer and extremely accurate. It's mated toa Alpha Platinum X graphite shaft, D5 at 45 inches,lasered for FLO, with Lamkin Xline Classic Sof-Cord grip. Thanks HarryS -Original Message-From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of [EMAIL PROTECTED]Sent: July 2, 2002 1:55 AMTo: [EMAIL PROTECTED]Subject: Re: ShopTalk: Putter Shaft Trimming In a message dated 7/1/2002 8:58:22 PM Pacific Daylight Time, [EMAIL PROTECTED] writes: This is such a basic question I'm almost afraid to ask it ... are there anyprotocols for tip trimming a steel putter shaft as a function of length?I've been buying the inexpensive steel shafts and installing them withoutthinking much about it until I made up an extra long putter (37") for a realtall fellow. The finished putter seemed much more flexible than any of the34 or 35 inch putters that I have put together. I've been conscious ofgetting swingweight into right ranges, but have not even thought about shafttip trimming, at least until now. If any of you have trimming guides, I'd really appreciate the info. Betteryet would be examples of how much to trim for various stiffness shafts.Thanks in advance, Ted WayHi Ted, Interesting question, I have always built putters by butt cutting only with whatever shafts are around unless I need a bent one of course.I have been told that over 90% of PGA pros have putters that swing weight to d-3, I wonder what they freq. to on average, I suspect all over the place.Just out of curiosity I "ll check a few, assuming I can clamp them.The graphite driver shafts that have done well over the last several year "s have something in common, the hm-series, pro-lights, and pf gold's are all about 3.5 torque when measured at about a 40" beam length, its possible that the best selling putters such as Answers, Odyseys's, Cameron's etc. may share common frequency's, maybe someone out there knows.David
