Swingweight:  
What It Is; Why It Is and How To Do It
By Jeff Jackson, Dynacraft Golf

            How heavy are your clubs?  Do they seem too heavy, too light or just right?  How can you determine the weight of the clubs that you have, and how can a clubmaker pre-calculate what the swingweight of your finished clubs may turn out to be?  The concept of swingweighting is a fairly simple one to understand provided certain parameters are followed.  A look at swingweighting and how it relates to clubmaking will take the guesswork out of making a club that will fit a given player properly and one that will be the correct swingweight.

            Beginning with a definition of swingweight, we find it to simply be the relationship of the weight distribution between the head and grip ends of the club.  That is, the more weight that is in the head end relative to the grip end, the higher the resulting swingweight of the club.  The opposite is true as well.  A club with a heavier grip will typically have a lower swingweight than will one with a lighter grip and/or heavier head.   Swingweight is expressed in arbitrary alpha-numeric units.  These units are expressed as C-9, D-0, D-1 and so on, with C-9 being the lightest swingweight and D-1 being the heaviest, for example. 

            Swingweight is measured by using a swingweight scale.  Just about all modern scales are based on a 14" fulcrum.  All of the weight to the grip end of the fulcrum is considered to be "grip weight."  All of the remaining weight of the club to the head end of the 14" balance point is considered to be "head weight."  Obviously, related to all adult length clubs, there will be more weight in the head end than the grip end of the club.  Any change in the weight of either the head, shaft or grip will cause a swingweight change.  A change in club length or the installation of a shaft with a different balance point will also cause a swingweight difference. 

            Just how much weight are we talking about when we talk about swingweight?  It will depend on where the weight is placed.  Looking at the club head itself, an addition of two grams to the head is the equivalent of one swingweight point.  Most players, regardless of their abilities, cannot discern between single swingweight points.  That is, it is nearly impossible to determine which club is heavier when comparing a D-2 club with one that weighs D-3.  To test this yourself, tape a dime on the back of the club.  A dime weighs very close to 2 grams.  Most likely you will not be able to tell to which club the dime was affixed.  Most players however, can tell 3-swingweight differences.  If two clubs, one weighing D-0 and one weighing D-4, are handed to a player, he or she will most likely be able to tell the D-4 club is heavier. 

            If a new grip is installed on a player's club, it could have some effect on the club's swingweight.  Let's say a jumbo grip weighing 66 grams is installed in place of a Victory grip weighing 50 grams.  Each 5 grams of weight change in a grip equates to a 1 swingweight change.  The heavier grip places more weight in the grip end of the club, making that end of the club heavier in relation to the rest of the club.  The heavier jumbo grip will yield a 3-swingweight - lighter - change in the club.  In an example of a 39-gram Winn type grip being installed in place of the 50-gram Victory, the swingweight would increase by approximately 2 points as this new grip weighs 11 grams less than the previous grip.  Any time a clubmaker replaces a grip with one of a different weight, the player should be made aware of the potential swingweight (and feel) change in the club.  It's a good idea to install the heavier or lighter grip on just one club and allow the player to take it to the course to test hit it.  This will tell if the new grip is acceptable to the player or not.

            A shaft replacement will change swingweight noticeably, especially if the change is one from steel to graphite or vice-versa.  For each 9 grams difference there is between shafts, there will be a 1-swingweight change in the club, provided no change in its length is made.  If a True Temper Dynamic shaft weighing 125 grams (raw weight) is replaced in a driver with a ProLite graphite weighing 66 grams, a weight decrease of 59 grams will occur.  This will yield a swingweight change of between 6 and 7 points.  Most graphite shafts are assembled at least 1" longer than steel versions.  A 1" change in length equates to a 6-swingweight change in weight.  Thus, the ProLite reshaft will weigh virtually the same as the steel-shafted club if it is assembled to a length 1" longer.  A clubmaker must be aware of the great changes in weight that are possible when changing clubs from one shaft to another. 

            The balance point of the shaft also influences a club's swingweight.  The lower the balance point of the shaft, the higher the swingweight, assuming all other factors are constant.  There is no hard and fast rule related to balance point and swingweight as there are literally thousands of balance point possibilities due to the shear number of graphite shafts available.  To determine if the shaft you are using has a low balance point or a higher one, simply balance it on a piece of angle iron or on your finger. The closer to the shaft tip that it balances, the more weight in located in the tip.  More tip weight indicates a low balance point shaft.  A hint here:  most shafts with oversize butts are low balance shafts since most of the weight has been removed form the butts of these clubs.

            OK, now that you know the effect of head weight, grip weight, shaft weight, club length and shaft balance point on swingweight, how can we calculate what the swingweight of a club will be prior to it being built?  In all honesty, the process, which seems daunting at first, is very simple.  If you know a baseline weight for each component along with a baseline weight for each club length, calculating finished swingweight is quite easy.  The following chart is useful in any and all club swingweighting calculations.  Study the chart and place a copy on the wall near your workbench - refer to it whenever you need to determine a swingweight prior to assembly.  It's simple, straightforward and requires no detailed equations to make it effective:

Swingweight and Component Weight
Head, Shaft, Grip & Length Related to Final Swingweight

NOTES

1.   All Swingweights are based on the raw weights of the components.  The shaft is not to be cut to length in order to pre-calculate swingweight.

2.   The balance point of the shaft, particularly certain graphite models, may change the final swingweight by several points.  A lower balance point will increase the swingweight; higher balance points lower it. 

3.   A change in the head weight by 2grams will yield a 1-swingweight change in the club.  Heavier heads increase swingweight; lighter ones decrease it.

4.   A change in shaft weight of 9 grams will yield a 1-swingweight change in the club.  Lighter shafts decrease swingweight. 

5.   A change in grip weight of 5 grams will change swingweight by 1 point.  Lighter grips increase swingweight; heavier ones decrease it.

6.   A 1/2" change in the length of a club causes a 3-swingweight point change.  Lengthening a club increases swingweight; making it shorter lowers it.

By using the weights in the above chart, swingweight can be determined prior to assembly.  Any deviations in component weight from the above can be calculated by adding or subtracting swingweight points for the final swingweight determination as explained in the Notes.

Procedural Examples:

EXAMPLE #1

      A clubmaker is using a 263 gram 6 iron head, a True Temper Dynamic Gold S300 shaft weighing 127 grams and a Lamkin Crossline Midsize grip that weighs 67 grams when assembling the club to a length of 37.5".  What is the resulting swingweight using these assembly parameters?

The head we are using is 2 grams lighter than the chart indicates .  This lighter head will contribute to a lighter swingweight - by 1 point.  The Dynamic Gold shaft weighs just 2 grams over the standard in our chart.  9 grams of shaft weight will cause a 1-swingweight change.  The Dynamic Gold shaft will cause a heavier swingweight - approximately 2-tenths of a point.  This is, for all practical purposes, inconsequential.  The Lamkin grip weighs 67 grams - 15 points higher than our 52-grams standard.  Each 5 grams in the grip is 1 point. The heavier grip yields a 3 swingweight point change - lighter - in the club.  Our example length is 1/2" longer than the chart length for a #6 iron.  Each 1/2" increase in length causes a 3-point increase in swingweight.

The net results:

       Head weight (2 grams lighter than in chart):  -1 swingweight

      Shaft weight (2 grams heavier than in chart):  +.2 swingweights

      Grip weight (15 grams heavier than in chart):  -3 swingweights

      Club length (1/2" longer than in chart):  +3 swingweights

      TOTAL: -.8 swingweights

As our chart indicates a swingweight of D-0, the is club will be approximately 1 swingweight less than that, or C-9.  Precisely, the weight would be C-9.2; as two-tenths of a swingweight point cannot be felt by a player, we round off the change to a full point, or C-9.

EXAMPLE #2

A clubmaker is asked to assemble a driver to a swingweight of D-2 at 45".  The components are as follows:  driver head weighing 200 grams, Tour Wrap grip weighing 52 grams, ProForce shaft weighing 58 grams.  Can the assembly be accomplished?

Beginning with the head weight, our driver is two grams heavier than the chart driver.  This will add 1 swingweight point. The Tour Wrap grip is the same as the weight in our chart; no change will occur through the use of this grip.  The ProForce shaft weighs 67 grams less than the specification in our swingweighting chart.  That difference equates to a swingweight change of approximately 7.5 points lower.  (9 X 8 = 72 & 9 x 7=63; each 9 grams of shaft weight is 1 swingweight.)  The added length of 2" over our standard will add 12 points to the club's weight.  (Each 1/2" is 3 points.)

The net results:

Head weight (2 grams heavier than our chart):  +1 swingweight

Grip weight (same as our chart):  no change

Shaft weight (70 grams lighter than our chart):  -8 points

Club length (2" longer than our chart):  + 12 points

TOTAL:  +5 swingweights

As the driver was to be assembled to a D-2 swingweight, the assembly cannot accommodate this weight.  The addition of 4.5 swingweight points to our chart baseline of D-0 will produce an assembled weight of D-4.5.  This is just over 3 points heavier than desired.  To achieve a D-2 weight, we could shorten the club 1/2", which will provide a reduction of the 3 points.  We could also find a heavier grip, provided the player would accept this.  A 67-gram model (Golf Pride's Jumbo Victory weighs 69 grams) will get us to the desired weight.  But, for all practical purposes, it is doubtful the player will go from a standard size and weight grip to a jumbo model just for the sake of swingweight.  We could use an even lighter shaft - by 27 grams.  This leaves two practical solutions to this assembly dilemma:  1) Build the club as is at D-4.5 or 2) Build it 1/2" short to obtain the D-2 weight.

EXAMPLE #3

A clubmaker is provided with 218 gram #3 wood head. He is also given a Microtaper shaft from Royal Precision that weighs 119 grams.  The grip is an Avon Chamois weighing 53 grams.  The specified length of the club is 42".  What will the final swingweight be?

This #3 wood head is substantially heavier than most.  It's 10-gram difference in weight will add 5 swingweights to the club.  The Microtaper shaft is 6 grams lighter than our 125-gram specification.  This will be a net lowering of the swingweight by 2/3 of point, or .7 swingweights.  The Chamois grip is only 1 gram different from our baseline; no change will result.  The length of the club also matches our chart; no difference will be caused by this length.

The net results:

Head weight (10 grams higher than our chart):  +5 swingweights

Grip weight (virtually the same as our chart):  no change

Shaft weight (6 grams lower than our chart):  -.7 swingweight

Club length (same as our chart):  no change

TOTAL:  +4.3 swingweights

The final swingweight of this club will be 4.3 swingweights more than our baseline of D-0, or D-4.3.