Tom, > Clubhead moment of intertia also has an effect on what the bulge should > be on a woodhead. The higher the MOI of the woodhead, the higher the > bulge radius should be (less curvature). This is because a high MOI > head will resist twisting more than a head with low MOI. So when you > have less twisting of the head from an off center hit, there will be > less of the gear effect to generate the hooking spin off the toe or > fading spin of the heel.
That makes sense. Since I was not an engineer by profession, how do you figure the MOI of a clubhead? Dad was certainly aware of MOI and advocated MOI matched iron sets (think I sent you the Wagglemeter patent for an MOI matching machine). But in his bulge patent, about line 10 right column, it states: "There have been some attempts to climinate the adverse dispersion causative factors. However, none have been completely or practically effective. Heretofore, there has been no appreciation that adverse dispersion due to off-center shots could be eliminated solely by means of positioning the center of gravity and/or accurately and meticulously curving the face relative to the center of gravity." Wonder why he (or the lawyer) made that statement? Is he leaving something unsaid about MOI? Has there been such a change in clubheads that the statement above would no longer be true? Bernie Writeto: [EMAIL PROTECTED] ----- Original Message ----- From: "Tom Wishon" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, August 06, 2003 12:33 PM Subject: RE: ShopTalk: Stirring the pot.... > Bernie: > > > Tom W > > -----Original Message----- > From: Bernie Baymiller [mailto:[EMAIL PROTECTED] > Sent: Wednesday, August 06, 2003 8:51 AM > To: [EMAIL PROTECTED] > Subject: Re: ShopTalk: Stirring the pot.... > > Bob, > > Gear effect is the result of a mis-hit off-center. It's always there > whether > there's a bulge or not. The bulge is meant to redirect the ball flight > so > that the gear effect spin brings the ball back to the target line on the > fairway, instead of the left or right rough. A hit toward the toe will > put > gear effect hooking spin on the ball, so the bulge aims the ball farther > right. A hit toward the heel will put gear effect slicing spin on the > ball, > so the bulge aims the ball farther to the left. The amount of mis-hit > from > center of the face and distance from the CG determines the amount of > bulge. > (There's a formula in dad's patent to figure the correct amount of > bulge.) > > In Tiger's case, the larger the radius and flatter the face, the farther > off > his target line he would be with a mis-hit...especially as hard and far > as > he hits the ball. Have to think that Pat is correct on this and Tiger > wouldn't mess with milling the bulge down. > > Bernie > Writeto: [EMAIL PROTECTED] > > > ----- Original Message ----- > From: "bob boone" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Wednesday, August 06, 2003 10:45 AM > Subject: RE: ShopTalk: Stirring the pot.... > > > > Bernie, > > Actually I think what the article said "was to reduce the bulge and > roll" > so > > I guess what they were doing was increasing the radius of bulge which > would > > only reduce the gear effect. I imagine Tiger is fairly consistent in > hitting > > in the center of the face except when he tries to really "jump" on > it!! I > > wish I had saved the write up but didn't!! The article didn't say > whether > > the milling process was being done on a "new" head or the head he was > > playing. > > > > -----Original Message----- > > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] > > Behalf Of Bernie Baymiller > > Sent: Wednesday, August 06, 2003 6:45 AM > > To: [EMAIL PROTECTED] > > Subject: Re: ShopTalk: Stirring the pot.... > > > > Took out the bulge? No wonder the guy is always in the trees. Mishit > off > > center just a bit with his swing speed and I can imagine there would > be > big > > time gear effect. The proper bulge is designed to correct for gear > > effect...assuming the head had the correct amount on it in the first > place. > > > > Bernie > > Writeto: [EMAIL PROTECTED] > > > > ----- Original Message ----- > > From: "bob boone" <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Sent: Tuesday, August 05, 2003 10:04 PM > > Subject: RE: ShopTalk: Stirring the pot.... > > > > > > > A couple of years ago there was an article in one of the Golf > publications > > > that said that Titleist has milled the face of Tigers driver to > remove > > bulge > > > and roll to get the proper spin and other things Tiger wanted. At > the > time > > I > > > wondered about that since taking an existing driver and removing > bulge > and > > > roll would thin out the face resulting in more COR most likely!! > Wonder > if > > > it was submitted for testing!!! > > > > > > -----Original Message----- > > > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] > > > Behalf Of The Kelley's > > > Sent: Tuesday, August 05, 2003 6:28 PM > > > To: [EMAIL PROTECTED] > > > Subject: RE: ShopTalk: Stirring the pot.... > > > > > > Tiger's driver (now) AFAIK is an 8.5 deg. Titleist 975D with a > 43.25" > > DGX100 > > > that's been tipped a significant amount. It looks like the first > step > is > > > about 4" from the top of the hosel. He was trying a lot of > different > > > configs with the Nike, including up to a 44" shaft. As an aside, he > > flirted > > > with graphite at one point last season, playing a fuji Pro95 for a > few > > > events. > > > > > > Pat K > > > > > > -----Original Message----- > > > From: [EMAIL PROTECTED] > > > [mailto:[EMAIL PROTECTED] Behalf Of Steve "Cub" > Culbreth > > > Sent: Tuesday, August 05, 2003 6:28 PM > > > To: [EMAIL PROTECTED] > > > Subject: Re: ShopTalk: Stirring the pot.... > > > > > > > > > Pat, > > > > > > I also understand that his Titleist is shorter (43") than the Nike > (?"). > > > > > > Cub > > > ----- Original Message ----- > > > From: <[EMAIL PROTECTED]> > > > To: <[EMAIL PROTECTED]> > > > Sent: Tuesday, August 05, 2003 4:17 AM > > > Subject: ShopTalk: Stirring the pot.... > > > > > > > > > > A little tidbit.... > > > > > > > > All who follow the PGA Tour will know that Tiger was whining about > > drivers > > > that exceed the legal COR limit being used. I figured I'd tap into > the > > > folks I know to see what specific drivers are at issue, and found > that > the > > > TM prototype 510 deep face driver is the suspected 'hot' driver. > (As an > > > aside, TM recently released this driver to the public as the '510 > Tour > > > Preferred' with an Edwin Watts price tag of $599 with a factory fuji > 757 > > > Speeder.) > > > > > > > > The driver is 390cc with a very deep face. I obtained a 9.5 > degree > > model > > > from the Van with a Harmon Tour GXX shaft. They said that the > 'identical' > > > head is now in stores (510 TP), no internal difference except the TP > > graphic > > > on it. I visually compared it to the retail 510 TP and it's the > same > > > visually, and the Edwin Watts cheapo swing speed/ballspeed device > data > > > indicates that the 2 clubs (van and retail) perform very close to > > identical > > > (757 vs Harmon notwithstanding) with respect to launch angle and > smash > > > factor. Both of these clubs have the USGA's blessing as legal, and > based > > on > > > the face design I'll offer that any grinding/milling on the face > would > > only > > > result on a paperweight for a clubhead rather than a longer driver. > > > > > > > > On the course, I understand what Tiger was whining about - this > club > > flat > > > out is over the top. I was using a TM 300 prototype that's 360cc. > > Although > > > both clubs are basically identical on perfect impact shots (both on > course > > > and on measured smash factor data), the 510 produces MUCH straighter > and > > > longer drives on less than perfect impact. Certainly this is > somewhat > due > > > to the larger size. > > > > > > > > Using the 750 yd bushnell yardage pro, we measured drives based on > > either > > > yardage pro measured distance from tee to flag (when possible) or > > scorecard > > > yardage. I hit the driver 9 times on a very level, slightly wet, > costal > > > South Carolina course. The longest was 343 yds, shortest 298, > average > > 316. > > > I missed 1 fairway by ~5yds where I didn't cut a corner enough (did > I > > > mention that this thing is LONG?). > > > > > > > > Interesting that Tiger went back to a driver that has less COR > than > the > > > Nike he was playing. It's also funny that the media has re-earthed > the > > > Tiger/Phil Mick. comments regarding Nike's technology. Tiger goes > back > to > > > an old-school, lower COR driver that he feels he controls better, > and > the > > > 'intelligent' media says Nike's technology with higher COR is behind > the > > > times. > > > > > > > > From what I've played, I can't understand why anyone playing for > their > > > dinner isn't hitting this TM. > > > > > > > > FWIW ($599 at your local Edwin :-0 ) > > > > > > > > Pat K > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >
