| Design advances in woods have everybody | | | | redistribute to lower the center of gravity |
| talking. From larger clubheads to the use of | | | | (COG) or improve moment of inertia (MOI). |
| exotic materials, today's woods are not only | | | | |
| designed better, they're also manufactured | | | | Re-positioning the COG, as I've explained in |
| better. Add to these changes the advances | | | | my golf tips, creates a more forgiving iron, |
| made in shaft technology, and you have | | | | with a larger sweet spot along the blade. |
| well-crafted metal woods engineered | | | | Thus, a mis-hit with an iron whose COG has |
| specifically to help you chop strokes off | | | | been re-distributed is more likely to stay on |
| your golf handicap. | | | | target than a similar shot with an iron whose |
| | | | COG has not been redistributed. Why? Because |
| But advances in iron design are helping | | | | a redistributed iron twists less in a |
| players as well. Golfers don't talk as much | | | | player's hand when the ball is mis-hit. The |
| about these advances as they do about those | | | | ball is also likely to travel farther on a |
| in woods, but they're just as significant for | | | | mis-hit as well. |
| improving your game. Iron advances, like | | | | |
| those made in woods, help you hit the ball | | | | MOI is a property of physics that indicates |
| longer and straighter, and shave strokes from | | | | the relative difference in how easy or |
| your golf handicap. Let's take a closer look | | | | difficult it will be to set any object in |
| as some of these design advances. | | | | motion about a defined axis of rotation. The |
| | | | higher the MOI of an object, the more force |
| Perimeter Weighting and Investment Casting | | | | will have to be applied to set that object in |
| | | | a rotational motion. Conversely, the lower |
| The revolution began forty years ago when | | | | the MOI, the less force needed to make the |
| Karsten Solheim turned traditional iron | | | | object rotate about an axis. |
| design on its head by introducing the | | | | |
| concepts of perimeter weighting and | | | | Shaft Lean and Swingweight |
| investment cast manufacturing. Since then the | | | | |
| advances have continued apace. | | | | Shaft lean is another new design concept that |
| | | | has found its way into club design. Shaft |
| Perimeter weighting (PW) creates a large | | | | lean is the angle at which the club must be |
| sweet spot on the club. PW repositions the | | | | delivered to the ball at impact to create |
| weight of the clubhead around the perimeter | | | | optimal pressure. Keep in mind that a ball |
| of the clubface instead of at its center. If | | | | compresses when hit, which causes it to |
| a player always hit the ball dead center, he | | | | spring off the face at maximum velocity, |
| or she would want a small sweet spot and no | | | | which leads to maximum distance. A |
| perimeter weighting. That way the club would | | | | forward-leaning shaft at impact, particularly |
| have as much physical mass directly behind | | | | when hitting the short- and mid irons is |
| the impact point as possible. However, if the | | | | critical to solid ball striking. |
| player is off even a millimeter, his or her | | | | |
| shot goes astray. By perimeter weighting golf | | | | Swing weight is also a key iron design |
| clubs, manufacturers' create maximum | | | | feature that affects performance. In |
| forgiveness in the club. | | | | non-technical terms, swingweight is a measure |
| | | | of how the weight of the club feels when it's |
| Investment casting is another key advancement | | | | swung. Why is it important? If your clubs do |
| in iron production. Many manufacturers | | | | not match in swingweight, they may not all |
| produce irons by pouring molten metal in a | | | | feel the same to you during your swing. That |
| pre-shaped cast. Cast irons provide the user | | | | slight change in feel could affect your |
| with less feel, but are less difficult to hit | | | | performance with those clubs. |
| consistently, and are therefore better suite | | | | |
| for players with high golf handicaps. Forged | | | | Philosophy and Intent Remain Key |
| irons have a softer feel and are less | | | | |
| forgiving to a user, but they cause the ball | | | | The introduction of concepts in club design, |
| to turn more off line when mis-hit. | | | | like swingweight and perimeter weighting, is |
| | | | not new in itself. Club manufacturers have |
| Thinner Designs | | | | always sought new ways to improve an iron's |
| | | | performance. What's new is their approach. |
| Solheim's advances were followed by the | | | | They are now trying to think of ways to |
| introduction of new materials, like scandium | | | | improve one area of the club while keeping |
| alloys, and of improved manufacturing | | | | the other areas consistent. |
| techniques, like computer-milled faces, in | | | | |
| iron design. These advances also took iron | | | | What's this mean for you? It means that you |
| design and construction in new directions. | | | | must decide which design ideas are worthwhile |
| | | | and which are just marketing hype. Next time |
| Club engineers were gaining a better | | | | you buy irons, don't just buy something |
| understanding of how each characteristic of a | | | | that's on sale. Study the philosophy behind |
| clubhead, like moment of inertia (MOI) and | | | | the model's design and construction and what |
| center of gravity), impacts club performance, | | | | the manufacturer is trying to achieve with |
| and were beginning to take advantage of this | | | | the club. If you do that, you'll get your |
| knowledge. Today's clubfaces, for example, | | | | money's worth and you'll get a set of irons |
| are thinner than their predecessors. Thin | | | | that will help you lower your golf handicap. |
| design frees up more mass that designers can | | | | |