Road Trip !!!
San Diego '98

Copyright  Dave Tutelman  -  August 30, 1998
All rights reserved 

Last week (8/8/98 - 8/15/98) my wife Honey and I went to southern California to visit relatives.  But I did manage to slip in a few golf-related activities.  And they made for a much more exciting vacation than I was expecting.  The golf highlights were:

  • Eighteen holes at Torrey Pines.
  • A tour of the Taylor Made facility, and a visit with Dick Rugge.
  • A tour of the Callaway facility, and a visit with Dick Helmstetter and Alastair Cochran.

Torrey Pines

For years, I had corresponded with Dale Winstead, whom I knew from rec.sport.golf.  I had promised him I'd look him up when I got to San Diego, so I dropped him some Email the week before vacation.  Unfortunately, he was on vacation that week, and didn't discover my Email till he returned the week I was there -- and I was incommunicado from my own Email.  Fortunately, I had given him my sister's Email as a "reach" address; turns out she works for the same company as Dale in the next building, so we had no trouble contacting one another.

My schedule for the week was filling up fast, so Dale tried for some tee times hoping for something we both could make.  He came up with Miramar (his home course) or a mid-afternoon tee time at Torrey Pines.  No contest!  Given an opportunity to play San Diego's most famous course, I wasn't going home without taking it.  We were very lucky to pick up -- on very short notice -- the last tee time of the day with a chance to finish 18 holes.

Dale was the perfect host, meeting me at the appointed time with a second set of clubs parked on a pull-cart for me.  We got acquainted while putting on the practice green for about 20 minutes, until the starter called us.

Torrey is a wonderful course for scenery.  We played the North Course; it's not as hard as the South, but more scenic (more holes along the ocean) and more enjoyable for a mid-handicapper like me.  Both courses are used in the annual PGA event played there, but only the South on the weekend.

You're always concious of the Pacific Ocean just down the cliffs through the ice plant and pines.  You better be concious of it; as Dale warned me, every green breaks that way.  Forget where the ocean is, and you're guaranteed to miss the putt.  The signature sixth hole is breathtaking.  It's a par-3 from a seriously elevated tee, to a narrow green with a bunker on the right, and nothing on the left but ice-plant-covered canyon.  There's a big tree to stop your ball from going over the cliffs if you airmail the green.  And beyond the tree is the Pacific, with La Jolla in the left of this picture postcard.

And the kikuyu rough!  When Gary McCord describes kikuyu grass as "bermuda on steroids", you better believe it.  Early in the round, I tried to hit a ball that was "down" in the rough, with a 5-iron; it felt like I hit it well, and the divot said I hit it well, but it only went 6 feet.  The next time I tried a 7-iron, with a similar result.  By the back nine, I realized that anything but an "up" lie in this rough required a wedge.  And it wasn't all that deep; it must be murder when they let it grow for the pros.  (The third time I hit a shot less than ten yards, Dale consolingly explained, "Kikuyu."  I replied, "Kiku-yu, too!"  No?  Guess you hadda be there.)

As the afternoon waned, the wildlife came out onto the course from the canyons between the fairways and the ocean.  Loads of jackrabbits cluttered the teeing areas and the rough.  With that many bunnies, there must be some predators.  Sure enough, we saw a coyote near the twelfth tee.  He watched us carefully from a distance of maybe twenty feet, but didn't run away.  Once he was convinced we were not going to bother him, he turned his attention back to the long-eared snacks.

On the seventeenth tee, the highest point on the course, we watched a red sun sinking to the Pacific, meeting its reflection at the horizon.  Beautiful as it was, I guess I was more distracted than inspired.  I made a triple-bogey mess of the hole, including drowning a ball in the only water that's actually in play on the course.  (While it's easy to go over the cliffs on Torrey's ocean holes, there's enough slope and vegetation that the ocean isn't really in play.)  We played the eighteenth in darkness, depending mostly on feel to determine the direction of the ball.  Even so, I recovered to par the par-five.  A good way to finish!

I did have a "clubmaker moment" in all this.  The clubs Dale brought for me were a set he made for himself several years ago, and has since replaced.  They were Golfsmith Square-Toe Blades on Dynamic Stiffs.  I found that, while I was hitting the short irons fine, I was pull-hooking the middle and long irons.  Consistently.  Disastrously (remember that kikuyu rough).  On the fourth tee, Dale mentioned that he had built them moment-of-inertia matched.  I said, "Then I know how to hit them," and proceeded to hit a long 3-iron with a bit of fade.  From then on, I was fine with the irons.  The secret was that I knew MOI-matched clubs need to be played from the same point in the stance.  I was hitting the PW and 9i fine from the middle of my stance, so I started playing all the irons from there.  It worked!

Thanks for a great day, Dale.

Taylor Made

The visit

I had made plans to finally meet Dick Rugge, with whom I've corresponded by Email for several years.  Dick is the Director of R&D for Taylor Made, and I visited him in his office at TM's factory in Carlsbad.  Dick is originally from the area where I live, and he learned to play golf at a course where Honey and I frequently play.  Before we settled down to talking golf clubs, we had a good time reminiscing about Colonial Terrace Golf Course.

Actually, Dick had been trying to recruit me for his engineering staff for a few years. When the Bubble Shaft came out, it took me about three weeks to figure out what it really did. I sent him a computer printout of clubhead speed with the bubble in different places on the shaft, and he wrote back, "Do you want a job?" He continued to ply me with comparisons of NJ (his relatives still live only a few miles from me) and San Diego (where my relatives live). He even phoned me one January afternoon while I was out shoveling snow to tell me, "It's 80° here, and I have a tee time this afternoon." But I was working in the computer-communications field (think late 1990s), and would have had to take a 30% pay cut to work anywhere in the golf industry.

So it was about time that Dick and I met.

One  interesting thing I learned was the backgrounds of the engineering staff at Taylor Made.  The high-end golf club industry took off just about the same time that the defense and aerospace industries were being downsized by government spending cuts.  Southern California was particularly hard hit.  That put a lot of resumes into circulation for engineers with backgrounds in space-age composites (e.g.- graphite/epoxy) and space-age metals (e.g.- titanium).  So the current makeup of a modern, high performance golf club is as much a factor of political history as of technology.

In addition to the "rocket scientists", the other engineering background Taylor Made employs is design engineering, including automotive designers; how can Detroit compare with San Diego as a work location?  And Dick himself has a background in quality engineering and management.

We talked a little about the market trends in new clubs, which gave me an opportunity to ask him how to pronounce "maraging" -- which I've seen in print, but not heard spoken by anybody I trusted.  He explained that it's short for "martensite aging", a metallurgical process for imparting great hardness and strength to steel.  So it's actually two words: "mar-aging", which is the key to pronouncing it.  BTW, he pointed out that the clubheads currently on the market use a super-strong steel alloy, but not a martensite-aged steel; so while the properties are similar to "mar-aged" steel, it really isn't.

Tour of R&D and prototyping lab

Taylor Made's R&D is a modern CAD/CAM setup.  The engineering stations have high-powered workstations with full CAD (Computer-Aided Design) capability.  I saw one designer working with "wire frame" pictures on his screen, that could be converted to color "photos" of the head at the touch of a button.  While I'm in the computer field, it has been a while since I looked at a professional CAD station.  I'm amazed at the speed and responsiveness of the current technology.

The CAD programs look like conventional design stations.  But behind the design is a full analysis of mass and strength properties.  Tweak the shape of the sole, and you'll not only change the look, but get a report on the change of CG, moment of inertia, any strength implications, etc.

When a design in the computer is ready for prototyping, the file describing it goes to the next room, the CAM (Computer-Aided Manufacturing) lab.  The file can be used to control a CNC (Computer Numerically Controlled) milling machine, to create a look-alike head.  This is done in a softer material than stainless steel or titanium; the head is for shape impressions (yes, they do put a shaft on it and ask pros what they think), but not for hitting golf balls.

But they do have a way to make a prototype head that will hit balls.  Remember that their clubs, like most these days, are cast using the "lost wax" method.  They can make a wax version of the computer file using a CNC machine that deposits a three-dimensional wax figure.  They build up a wax positive, then use it as the input to a prototype foundry to cast the head in steel or titanium.

They have a shaft prototyping lab as well, where they can make full-scale, full-performance shafts.  The Bubble Shaft is Taylor Made's own design, and is built using their own process.  The difference is in how the graphite/epoxy mix is held in place during curing:

  • In the conventional process, the epoxy-impregnated sheet is wrapped around a mandrel, which is the "mold" for the inside diameter of the shaft.  Then heat-shrink tubing is placed over the assembly and shrunk, so it presses the graphite/epoxy into place around the mandrel.
  • In Taylor-Made's process, the mandrel is slipped into a flexible sheath (no wisecracks, guys) before the graphite/epoxy is wrapped on it.  Then the combination is put into a precision internal mold, and the flexible sheath is inflated to press it outward against the mold.

The advantages of the Taylor Made process are (1) a higher pressure can be obtained than from heat-shrink tubing, so a more uniform, predictable layup can be achieved, and (2) the precision mold is on the outside of the shaft (where you want it) so the outside dimensions and finish are controlled, not the inside.

Tour of assembly facility

The only components Taylor Made makes on premises are the prototypes.  The production components are subcontracted out, but to their design and specs -- and, in the case of shafts -- their process.  But they do assemble the components into finished clubs at the plant.

It isn't the classical assembly-line setup.  Each model has a short assembly line, and all the short lines operate in parallel.  Even though it isn't one big assembly line, they do things quite differently from what we know as custom clubmakers.  For instance:

  • The grip goes on the shaft before the head; more on that later.
  • Several stations (gripping, epoxying the head) have lasers projecting a red line on the club.  This is used to align a "target point" on the grip, so the finished club comes out with the grip, the shaft logo, and the clubface all in the desired alignment.
  • They pour epoxy into the hosel to assemble it, rather than smearing it sparingly on the shaft.  But there is method to their madness.  Before assembly, the shaft is plugged flush with the tip.  Then a pre-measured dose of epoxy and shafting beads is machine-injected into the hosel.  Then the shaft is jammed into the hosel, displacing the epoxy mixture up around the shaft.  It displaces because the tip is plugged, so there's noplace else for it to go.  The dose is just the right size so it fills the ferrule coning, but doesn't leak out between hosel and ferrule.
  • As soon as the shaft is inserted into the hosel, it is put in a stand, the shaft/grip combination is laser-aligned to the head, and the part of the stand that wraps around the hosel heats it to 230*F.  In two minutes of accelerated curing, the club is ready to hit balls.  While they do use a specially formulated epoxy for optimal cure at two minutes, Dick tells me that every epoxy will cure both stronger and faster at elevated temperatures.  In the case of the epoxy they use, it would cure in 24 hours at room temperature (just like the Golfsmith stuff); but the final shear strength would be much less than half the strength that the accelerated-cure stuff has after two minutes.
  • To my surprise, the last step is done exactly the same as we do.  The ferrule is taken down to meet the hosel by hand on a belt sander.  For all the discussions we indulge in about better ways to do this, Taylor Made hasn't found one.

Near the assembly line is the "PGA Shop", where they do special assembly or modifications for the clubs for the touring pros they sponsor.  Now here's the sort of stuff we'd be used to seeing: bending machines, grinders for altering toplines and soles, bins of grips of most of the usual models (yes, they had the corded green victories I prefer), etc.  The clubs in progress were on a rack, and the nameplate had a card in it marked "Lee Janzen".  Honey asked, "When they're done, you'll mail it to him?"  We were told, "When they're done, we'll deliver it to him!"

Callaway

The tour

Callaway has a standard tour of the plant, open to the general public.  Let me recommend it; I learned more than I expected to on the tour, and came away with more respect for Callaway's quality control than I had when I arrived.  Besides that, it was real fun for an amateur clubmaker to see how the big guys do it.

I asked for a Thursday tour, but they came back to me with a proposal for Friday if I could make it. I could, so we did. I thought it was because they were already full on Thursday, but it turned out to be more involved than that. See below.

The tour started in the incoming inspection department.  Callaway buys all its parts; they too are an assembly company, not a foundry or a shaft maker.  They use over half a dozen foundries and another half dozen shaft manufacturers as suppliers, who build components to Callaway's specs.  The shaft makers include several of "the usual suspects".

Incoming parts are inspected on a number of parameters.  Weight, for instance, is fully checked for all components.  (I noticed that the Great Big Bertha heads, being inspected when our group passed, weighed in the 187-190 gram range; that's 10 grams lighter than we component clubmakers would see on a driver head.)  Other parameters are measured either fully or on a sampled inspection basis.  For instance, flex is checked by statistical sampling, not full inspection.

They accelerate the curing process of the epoxy.  Instead of a 24-hour room-temperature cure, they give it one hour at 180*F.  They have a room-sized "oven", where they place an hour's worth of assembled clubs on wheeled curing racks.  At the end of an hour, they wheel out the racks of cured clubs and wheel in a new set of racks.  (I didn't see The Changing Of The Racks, so I'm not sure how it works.  I suspect it's largely automatic.  Certainly you couldn't send people in to do it manually unless you cooled the whole room, which would be a big waste of energy.  Or maybe people with full thermal suits and masks...)

There's an interesting step toward the end of the assembly; they adjust the swingweight remarkably precisely.  The heads are made with a hole in the sole.  At the swingweighting station, the club is put in a "cradle" which is a computer-input swingweight scale.  The computer measures the actual swingweight, and computes how much epoxy in the clubhead would bring the swingweight to the target for that model club.  It injects that amount of epoxy into the hole.  The the club is then oriented so the epoxy gravitates to the heel while it cures.  I asked our guide how accurately the process swingweights the clubs; she said to within a half a gram.  I suspect she meant a half swingweight point, which is plenty of precision even for a good custom clubmaker.  Half a gram would be a quarter of a swingweight point, overkill IMHO.

Callaway's design requires more manufacturing steps than most clubs.  The through-bore plug and the epoxy-swingweighting require an extra cure step and an extra trip to the "grinding room", where the plugs are cut flush with the sole.

You can order clubs to your own specs at no extra price.  But there must be an extra cost for Callaway, because it's handled on a separate, much-lower-volume assembly line in their "special order" assembly room.

I saw the new Steelhead club.  It's obviously Callaway's answer to low-profile fairway woods, as you already know if you've seen the commercials.  The premise is that low-CG is good, but low profile isn't. The new clubs promise a lower CG with a full-height face.  The principle is a very light crown and extra steel in the soleplate.  I agree completely with the design intent, but was skeptical about how well the club meets that intent.  I have since seen their numbers, and am impressed.  For instance, comparing the 13* strong-3 clubs, the Steelhead's CG is 14% (0.1") lower than the Orlimar, while the face is 20% deeper.  Just from the numbers, the Steelhead would appear to be a better club from the tee and the rough, and certainly no worse from the fairway.  Assuming the numbers really are representative of the clubs in question, they are probably pushing the envelope moving mass around while preserving strength.  Some interesting things to watch over the coming year:

  • Repair rates: did they leave enough safety margin?  If you remember, the early Big Berthas snapped graphite shafts.  In addition to pioneering the larger head, that model eventually pioneered the reinforced shaft tip.  Now we'll see how well reinforced the face, crown, and walls are, and still allow that much steel to be moved to the sole.
  • Clones: can't you just see the "Stealheads"?  These are likely to be, more than usual, a look-alike that can't deliver performance.  I suspect moving that much metal around will require more than the usual dimensional control in casting, and clone foundries are more interested in looks than specs.

While on the tour, I came to a possible speculative conclusion:
Callaway puts more control into heft feel than flex feel (complete incoming weighing of shafts and heads, and a post-assembly swingweight trim, vs a sampled inspection of flex).  Do they believe that heft feel is more important?  It would appear so.

Since returning, I got some data confirming this speculation.  Bob Schreiner measured two sets of Big Bertha irons, an X-12 and a Tungsten-Titanium, and sent me the swingweights and frequencies.  The data shows that:

  • Except for one tungsten-titanium, all the swingweights are in a 1-point band.  That's plus/minus a half swingweight point.  Very good, tight tolerances; I'm pleased when my sets come out that well matched. By the way, the one iron outside the band is only a half point off.
  • The frequencies of the X-12 are also remarkably tight (especially for graphite shafts).   All but one were within 3cpm of a best-fit Brunswick slope; the one outlier was 6cpm off.  Except for the outlier, that would be good even for steel shafts. The Tungsten-Titaniums weren't quite as good, with three of the clubs being 4cpm off, but nothing worse.  So the sampled inspection does let a few get through, but it's better than anything I've seen in other OEM graphite-shafted clubs, and almost as good as most companies' steel shafts.  But it's clear that the sampled inspection does let a few wild ones get through.

BTW, the swingweights were D-0.  The best-fit Brunswick slope for the data was a 4.0 for an "R" flex set, and 4.8 for a "Firm".

The meeting

After the tour, we tourists were milling around the reception area with snacks and Callaway brochures. A security guy worked his way through the crowd trying to find Dave Tutelman. So I identified myself, wondering, "What did I do now?" He told me, "Mr Helmstetter would like to see you in the Test Center, if you have time." Well, I knew that Dick Helmstetter was the design and engineering head for Callaway, and they told me that the Test Center was their R&D campus. They gave me directions and we were off.

The test center was about a mile from the plant. It's a three-story building bordering on a luxury high-tech driving range. We were met by Sam Nicolas (I believe he's the manager of R&D), and he took Honey and me to a conference room, where we were joined by:

  • Dick Helmstetter, designer of the Big Bertha clubs.  His title is Senior Executive VP and Chief of New Products; you've seen him in Callaway's ads on TV and in magazines.
  • Alastair Cochran, author of "The Search for the Perfect Swing", technical advisor to the R&A.  His book was my primer on golf club engineering when I started out, and there's still nothing around that's nearly as good.  He was apparently visiting California, and I just lucked into the thrill of meeting him.
  • Jeff Colton, Technical Advisor to Chief of New Products.
Apparently the change from Thursday to Friday was to allow me to attend this meeting, which hugely flatters me. Not just that I was invited, but that Helmstetter recognized my name from the Internet (probably R.S.G.) and connected it with the request for a tour. I gushed about meeting Cochran, the author of my favorite golf science book, and Dick decided I should be able to leave with a signed copy of it. They had to steal a copy from their engineering library (with margin notes from their engineering staff), Alastair signed it, and it is on my bookshelf today.

We talked for about an hour about the "hot topics" in club technology.  Among the topics we hit:

  • The "springy clubface" controversy.  This was -- obviously -- the biggest discussion because it's the current hottest topic.  Some of the things I carried away:
    • The energy-loss split between ball and clubhead is upwards of 95%-5%.  That's close to the assumptions in my "hardness" article.
    • There is a 2-3% increase in initial ball velocity for some "modern" clubs, compared with a perfectly rigid clubhead.  (I extrapolated this to a 5% distance increase;. Alastair thought it wasn't that much, so I went back and calculated it -- using, of course, the equations in Appendix I of his book. He was right; it was more like 4%.)
    • "Physics sets the limit."  This seems to have become the club industry's mantra.  They tend to ridicule the notion that there will be big distance gains in the future from clubhead technology.  Yes, physics does set a limit; but I think it's incumbent on everyone to make clear what that limit is.  I'll do that calculation; the limit set by physics (as opposed to current technology) can't be all that hard to calculate.  And if the limit is much beyond what we have already, I think legislation is called for.
    • Surveys of golfers (including an R&A survey cited by Alastair) say that the game's constituency wants to have a single rule.  So a "baseball solution" (remember that professional baseball players play with wooden bats, and everyone else aluminum) is not an acceptable solution for golf clubs.
  • We've all been making a lot of fun of Top-Flite's concept of a ball that "matches" a club.  But if the face flexes, it begins to make some sense.  You want the ball's vibrational frequency to match the clubface's.  (No, not the CPM of the whole club, but the vibration of the clubface in the clubhead.)  You want both to be rebounding at the same time, not one rebounding while the other is absorbing.  So the idea of "impedance matching" a clubhead to a ball isn't all that wild any more.
  • Golf club technology seems to be outstripping the ability of the patent office to police it.  Dick cited a 1991 Japanese patent (issued in the USA in 1997) that clearly has no merit.  Not only is the analysis flawed, but there were clubheads in the 1980s and earlier that "violated" the patent.  Even so, there are already some companies paying big bucks in royalties.  (What makes me think that Callaway would rather fight than pay? :-)
  • Measurement is becoming one of the big things in advancing the art of club design.  Callaway can now measure duration of impact to less than a microsecond, closer than anybody else.  (They had some unusual and impressive-looking instruments that they hurried me past as we walked to the conference room.)  And of course, the coming battle over springy faces will turn in large part on the precision of the test to measure the effect of the clubface on ball velocity -- both the actual precision and the precision that is generally believed by the public and the clubmakers.

At the end of an hour, Dick said that he had work yet to be done today, and excused himself.  On our way out, we saw him hitting balls at the range.  (Range?  No, sorry, that's the Test Center.  How about a job where the system test lab is a driving range?)  And I walked away with a signed copy of my favorite book on golf science.  Thanks for inviting me, Sam; I'm still pinching myself.

TM/Callaway Comparison

How about comparing the way Callaway and Taylor Made build their clubs:

  • Functional vs product organization:  Callaway uses a functionally-oriented "assembly line".  Except for special orders, they have just two lines (one for irons and one for metalwoods).  Taylor Made has a bunch of very small "lines", one per model, with no more than one "functional" person per "line".  A couple of reasons for the difference:
    • Callaway makes a lot more clubs per day.
    • Callaway has more steps in the process.  The through-bore and the swingweight adjustment require an additional trip to the grinding room and an additional cure step.
  • Accelerated curing:  Both elevate temperature for accelerated curing.  Taylor Made uses more elevation and faster cure (230*F @ 2 minutes, vs 180*F @ 60 minutes).
  • Head suppliers:  Both use outside foundries, but primarily or exclusively domestic US companies.  Taylor Made's foundries are a subset of Callaway's.