Iron (golf)

[3] Historically all irons were forged from a flat piece of metal, which produced a thin clubhead that resembled a blade.

Modern investment casting processes enabled manufacturers to easily mass-produce clubs with consistent properties.

The resulting club is also generally thought to have an improved "feel" due to the softer consistency of the forged metal as opposed to cast.

Manufacturers sometimes try to combine the characteristics of both muscle and cavity backed irons, which has resulted in terminology such as "cut-muscle", or "split-cavity" to describe these designs.

A muscle back is the more traditional design and consists of a solid metal head, typically made of forged iron.

As such, these clubs are said to have a smaller "sweet spot", requiring greater skill and a more consistent swing to make accurate, straight shots.

Novice golfers with less consistent swing fundamentals can easily mis-hit these clubs, causing shots to launch or curve off of the intended line of play (such as "pushing", "pulling", "slicing" or "hooking").

This has the general effect of lowering the clubhead's center of mass, placing it underneath that of the ball allowing for a higher launch angle for a given loft.

Club sets with more extreme perimeter weighting, giving the clubhead a very wide sole, are typically known as "game improvement irons", because they allow novice and casual amateur players to get the ball up in the air more consistently, and make straighter and more accurate shots despite their less consistent ball-striking skill.

This generally improves their final score as compared to a round played with harder-to-hit muscle-back designs causing more errant shots and thus more penalty strokes.

The tendency of the clubs to correct mis-hits will frustrate a golfer's attempts to intentionally hit a curved shot (a "fade" or "draw"), for instance to avoid an obstacle lying along a straight flight path, or to counter a rightward or leftward slope to the fairway that would make a straight shot roll into the rough.

This allows the golfer to "work the ball" while still giving some advantage based on the lower center of mass as compared to older designs.

Investment casting, while allowing for a greater range of design options, produces a very stiff and inflexible head that can be difficult to adjust for a player's desired lie and loft.

By forcing manufacturers to lessen the depth and cut on the grooves, the new rules will penalize shots from longer grass slightly more and put a premium on hitting the fairway.

Many modern irons have a more offset hosel, integrated into the clubhead at a lower point and further from the hitting area of the club.

Modern grips are generally made from rubber, sometimes inlaid with cord, but some players still prefer a traditional leather wrap.

Even though materials advances have resulted in more durable, longer-lasting soft grips, they still require frequent replacement as they wear, dry out or harden.

[citation needed] Often called a butter knife because of how it looks, the 1 iron has the least surface area on its face and so is commonly regarded as the most difficult club in the bag to hit.

[citation needed] The driving iron is virtually obsolete as its nominal range easily falls into that of the easier-to-hit fairway woods, although some sets still include one and it can be purchased separately as a custom club.

As such, they are less commonly seen in players' bags, usually replaced with higher-lofted fairway woods like the 5 and 7, or with hybrid clubs that have similar overall performance but are easier to hit.

If the long irons are used, they are often seen with graphite shafts to add additional clubhead speed to the average golfer's swing by storing energy from the downswing and releasing it at impact.

They have the highest-mass clubheads and the shortest shafts of the numbered irons, and are used for shots requiring high loft or moderate to short distance (typically between 130 and 150 yards with a full swing).

The short irons are traditionally regarded as the easiest to hit; however they are typically used in situations requiring very high accuracy, and so it becomes critical to minimize any effect of mis-hits.

This wide sole was added to other high-lofted irons to add mass to the clubhead (compensating for the shorter shafts) and gives wedges their name, alluding to the clubs' appearances in profile.

This in turn requires more attention paid to the selection of fairway woods or hybrids to produce more evenly-distributed average distances between the driver and the long to mid irons.

The lie angle of an iron is often adjusted to fit a golfer's swing so that the head of the club is in the right position at impact.