SPINE FINDING AND WHAT TO DO WITH THEM AFTER YOU FIND THEM

by Bill Day
Golf Equipment Professional
PCS "Class A" Clubmaker
GCA Advanced Professional Clubmaker

WHAT ARE SPINES?

Spines exist in all golf shafts regardless of material (steel, titanium, graphite, etc.) and regardless

of manufacturing process (extruded, welded, sheet wrapped, filament wound, etc.) A Spine can

be visualized as a longitudinal line or plane on a golf shaft that is more resistant to bending than

any other line or plane. In the extreme case, the shaft can be considered as unsymmetrical as a

yardstick with the narrow width representing the spine and the wide width representing a more

flexible plane. In one direction the yardstick bends easily; in the other it is difficult to bend and

may break.

In February 1999 the USGA Implements and Ball Committee modified its rule on golf shafts

which required that they "bend symmetrically in all directions". The reason for the change is

that it was proven to them that today's technology would not support manufacturing of a shaft

with these "symmetrical properties" without raising prices to unrealistic levels. The USGA

concluded that it would "not be against the rule" for club (and shaft) manufacturers to "orient

the shaft in the clubhead such that the shaft appeared to bend symmetrically in all directions".

Thanks to Dick Weiss, the patent owner for spine finding and orientation, the golf club industry

now has a new method for golf club improvement that, in conjunction with frequency matching,

can provide the most consistent golf clubs ever built.

HOW DO YOU FIND A SPINE?

The butt of the golf shaft is placed in a "holder" of some type (Spine Finder) which allows the

golf shaft to be "loaded" or bent, and at the same time allows the shaft to rotate freely. When

the shaft is rotated, the resistance to the force bending the shaft varies throughout 360 degrees

rotation. When a "strong point" or "spine" is approached, the shaft becomes unstable and wants

to rotate "away" from the spine. Where does it go? It rotates to the nearest "valley" which is a

position of stability (also called the "Neutral Bending Position" or NBP). There are simple

instruments called "spinefinders" that are used hold the shaft in position, while loading the shaft

and rotating it to to locate the spines and NBPs. (Spinefinding devices range in price from under

$50.00 to $2500.00 or more. The lower priced model I have does the job well, and detects all

spines and valleys (NBPs).

Golfsmith International Inc., under license from Dick Weiss, the patent holder, provides a spine

finding and shaft orientation marking service. Their machine for doing this is a much more

expensive, computer controlled machine designed for accurate identification marking and high

volume use compared to the simple manually operated "spinefinders".

COMMON TYPES OF SHAFT SPINES

There are two major types of shafts identifiable by their spine complement. Note that a

"perfect" shaft would bend equally in all directions and have no detectable spines or NBPs.

Type 1: S-180-N This is a very common type shaft and is usually one made of steel,

Titanium, or some other alloy or metal matrix. Some graphite shafts also exhibit this

characteristic. The terminology "S-180-N" indicates that there is a Spine located 180 degrees in

circumference from a NBP.

Type 2: S1-180-S2, N1-180-N2 This type of shaft and spine pattern is almost always

some type of graphite shaft, either sheet wrapped or filament wound. The spine pattern

indicated is that the prominent spine (S1) is located 180 degrees from (S2) which is a spine of

lesser magnitude. The NBPs are also noted as (N1) more prominent than (N2) and also 180

degrees away from each other. In addition the spines are located 90 degrees from the NBPs, so

that a complete spine description could read "S1-90-N1-90-S2-90-N2-90" for a full 360 degree

circumference notation.

Type 3: Other This is a "catch-all" category that includes anything other than Type 1 or

Type 2 shafts. There are some shafts that may have three sets of spines and NBPs. Others may

have a noticeable NBP but no real prominent spine. This includes some new patterns S1-120-

N1-120-S2 and N1-120-S1-120-N2 (these are really strange).

SHAFT ORIENTATION IN A CLUB HEAD

By properly orienting the shaft in a clubhead, the maximum performance of the golf club can be

obtained. This statement assumes that the golf club assembly has been designed by the

Clubmaker to obtain the proper swingweight, length, and frequency (stiffness) at the specific

shaft orientation prior to final assembly of the golf club. In essence, the club will perform as if

the shaft had symmetrical bending properties in all directions.

When specific orientations are discussed, a clock face is used for descriptive purposes with the

"toe" of the club at the 12 o'clock position for a right handed golfer. The swing plane will be

from 3 o'clock to 9 o'clock, with the ball setting at the 9 o'clock position.

Type 1 shaft: There are two optional orientations available. S - 9 o'clock, N - 3-o'clock

and the opposite with S at 3 o'clock and N at 9 o'clock. Testing information to date indicates

that the S - 9 o'clock position offers slightly more accuracy while S - 3 o'clock offers slightly

more distance.

Type 2 shaft: There are again two optional orientations available. N1 - 9 o'clock and

the opposite N2 - 3 o'clock. The important thing about this shaft type is that the more stable

"N" locations are in line with the swing plane, offering maximum stability along the swing plane

line. In addition the stronger S1-S2 spines are aligned in the 6 -12 o'clock plane and help to

minimize "toe droop" as the clubhead approaches the ball during the swing. This appears to be

an ideal type of shaft since it offers the best swing plane stability while minimizing toe droop.

Whether this is truly better than a so-called "perfect shaft" is unknown, since a perfect shaft

which meets the USGA rules can't be built in an economic manner.

TWEAKING THE FINAL ASSEMBLY CONFIGURATION

Prior to Frequency Matching/Shaft Tipping and epoxying the golf club assembly in its final

configuration, it is necessary to do a final bit of "tweaking" to achieve the best spine orientation

performance. With the clubhead in the final orientation, the shaft must be "twanged" or

oscillated in the 3 -9 o'clock swing plane of the club with the clubhead held firmly in position.

The object is to achieve Flat Line Oscillation (FLO) of the assembly - that is, the club should

move only in the swing plane, with no movement at right angles to this plane. If there is any

tendency for the clubhead/shaft to move in directions (oval or circular pattern) away from the

swing plane, the clubhead/shaft orientation should be changed in 1-2 degree increments until

FLO is achieved. The final shaft-head orientation should be marked in order to regain this

position after epoxy had been applied and the assembly positioned for drying.

CAUTION FOR RE-WORKING EXISTING CLUBS

There are many pitfalls to be avoided in re-working existing clubs to orient their spines. For

instance, thru-bore clubs such as Callaway and Titleist create problems since the shaft tip has to

be cut off and finished smoothly to the club head. Tipping the shaft will increase the stiffness

and some swingweight will be lost.

For any club, especially Type 2 graphite, the frequency or stiffness of the club will vary as the

shaft is rotated to the new alignment. Some of the shafts may vary 15-20 cpm (two flexes)

around the circumference, and will be stiffer in the S1-S2 plane than in the N1-N2 plane. Its

difficult to tell a customer that his club is now two flexes weaker than it started out! But it's a

fact of life, and the customer should be forewarned that he may need a new shaft.

Wilson Fat Shaft clubs are real nasty because of their size and construction. Replacement

ferrules are not available to the clubmaker at this time.

Oversize shaft tips require different size ferrules also - be sure you have the right size on hand

before re-orienting the shaft for a customer.

WHAT CLUBS SHOULD BE SPINED?

In my shop, I swingweight match, frequency match and orient the shaft properly on all new

clubs. In this way I can assure myself and the customer that they have the best product

available.

When I am re-working existing clubs, I think that all woods and the long irons (through 5 iron)

should have the shafts properly oriented. I don't think that much benefit is achieved for the

average golfer to have the shorter irons re-worked for shaft orientation. For the better golfers

who have a good sense of feel, they my want them all re-worked - because lets face it the re-

worked clubs do feel better than the random spine placement that exists in nearly all golf clubs

today.

WHERE ARE WE AND WHERE ARE WE GOING

To the best of my knowledge, none of the OEM manufacturers of golf clubs or shafts have an

agreement with Dick Weiss, the owner of the patent on shaft spining. The only license

agreement in existence to date is the one wherein Golfsmith sells a shaft spining service to their

customers for $6.95 per shaft. Also at the current time, there are very few clubmakers equipped

to provide shaft orientation services because of lack of tools, lack of knowledge or both.

Licensing under the patent for independent clubmakers will be addressed in the future.

Some clubmakers (like fishing rod makers) have been working with spines for years. What

effect this will have on the Weiss-owned patent is hard to say. I do know that Weiss has spent at

least a million dollars to date in acquiring and preparing to defend the patent, so you can see he

doesn't take this lightly. Dick continues development of spine-related technology and tools,

some of which will be revealed at the 1999 Golf Clubmakers Association Conference at

Golfsmith in mid-October.

How effective is shaft orientation in clubs? Tom Wishon, Chief Technical Officer of Golfsmith

has said that this is the next step beyond frequency matching of golf clubs, but to do it properly

the set of clubs must be frequency matched in conjunction with spine orientation to achieve the

effect desired. If a set of clubs is just shaft-oriented, with no attempt to frequency match, they

may be worse than a set of clubs without shaft orientation.

>From personal experience, I have found that frequency matching and spine orienting my woods

has resulted in better feeling, longer and more accurate clubs. "Longer" is 5-10 yards, not 25-50

yards. Feel is that of being "real solid" when the ball is hit. Perhaps the "feel" gives me a sense

of better accuracy since I cannot express that in meaningful numbers. For the irons, I know that

the long irons are definitely better. A question still exists on the short irons since I am not a

good judge of this at this point in time - we'll see. In the meantime, I even orient the shaft in

putters that I am building new or re-shafting since I believe in the theory and technique.

Bill Day owns and operates Bill's Custom Golf in St .George, UT. For questions, comments and

help, contact Bill at (435) 674-3544; Fax at (435) 688-2110; or E-Mail at billday@infowest.com.