Bending Golf Clubs: Facts & Fallacies

Technology - Apr 23rd, 2009

An Industry Professional’s Guide To Angle Adjustments

As an industry professional you know that angle bending is among the fastest ways to improve a player’s ball flight. Whether changing the lie to improve accuracy or changing loft to make certain that the player’s clubs are progressively consistent, angle bending is a major factor in club performance. When it comes to loft and lie, many players have incorrect ideas about what can be done and what effect changes may have on playability. Being an industry professional, it is important to become knowledgeable to all facets of club bending. When you do so, you become the equipment expert and your golfers will rely on you as their source of equipment alteration. Here are some facts and fallacies for you to be aware of so you can better serve the needs of your golfers.

Can cast clubs be bent?

Most irons can be bent, but the question of being able to bend cast clubs is still asked. The simple answer to that question is “yes”. 17-4 stainless steel cast irons will be more difficult to bend since they are harder (C34-38 on the Rockwell Scale) than 431 (HRC18-25) or carbon steel (high B’s on the scale) heads. Keep in mind that we are assuming the iron has the proper heat treatment and annealing that will permit bending. Annealing ensures a more consistent grain structure in the metal. Heat treatment makes the head hard enough to withstand constant golf ball impacts. Also, the club must have a hosel design that will allow bending. Special bars may be required for certain hosel designs such as those with a shorter hosel. With proper equipment nearly all hosel designs can be bent accurately and consistently ensuring properly fitted clubs for your golfers.

There is also a misconception that clubs that have been bent have “memory” that makes them naturally return to the original specification. This is simply not true. Once a club is bent to a given specification it will stay there until changed by an outside force of either bending again or striking a hard object. Loft and lie changes are more or less permanent.

Can today’s metal woods be bent?

Even though a lot of people will immediately say no, the correct answer is “yes” with certain requirements. While there are limitations, many of today’s metal woods are indeed bendable, especially stainless steel heads. Forged titanium models are bendable as well. Their softer titanium structure allows bending. Provided the hosel of the wood is long enough to allow the bending bar to fit over its length, metal woods can be bent to custom fit a player. This applies to both face angle and lie.

What about bending the loft of a metal wood? When you bend the hosel toward or away from the face plane you open or close the club’s face angle. This will change the playing loft of the club by changing the trajectory of the ball but it will potentially cause misdirected shots. Don’t be misled that tour professionals de-loft their drivers and get more distance.

Do club companies manufacture progressively consistent clubs?

In short the answer is “no”. While they certainly try to make consistent product, they do not necessarily do so. It would be nice to believe that every set comes from the factory with precise specifications, but this is just not the case. There are often inconsistencies in the lofts and lies of the clubs. Clubs are mass-produced with certain +/- manufacturing tolerances in every factory. However, you can easily bend the lofts and lies to be progressively consistent from one club to the next with zero tolerance. Plus you can bend the angles to a consistent specification precisely fit for any golfer.

Are there standards for loft and lie angles?

One of the most overused words in the golf industry is “Standard.” Instead of the word standard, perhaps the word average should be used. Or maybe no word should be used.

A quick look on the internet at specifications for the best selling #5 irons from four major manufacturers shows lie angles of 60.5, 60.8, 61 & 61.3 degrees. Not surprisingly there is no stated tolerance on any site, making one wonder just how close that 61.3-degree specification is. A look at standard lofts of #5 irons from these same manufacturers shows that two use 27 degrees while one is at 28 and one at 29.

As an industry professional you should use the manufacturer’s specifications as a reference only. When adjusting loft ask the player if they have any distance gaps between clubs that a loft change of a degree or two will correct.

The word standard really doesn’t come into play with club performance fitting. Each player should be matched to his or her own individual specifications. If you want to call those specifications standard for that player, fine. But make sure you record the details for future reference, thereby setting their “standard” for improved individual performance.

It is vital to know the exact specification of the club’s angles when checking for a proper fit using a lie board test. The lie board test could show the need for the club to be more upright or flatter. The performance is the key element during the lie test, which determines a specific angle in degrees. The test club must be measured and adjusted to the new angle. Remember the set is not necessarily progressively consistent and therefore each club should be bent to a predetermined angle in relation to the test club. Do not bend every club in the set by the proverbial “2 degrees up or flat” thinking you adjusted the entire set consistently.

How does bending influence bounce?

Any change in a club’s loft will correspondingly change the club’s bounce. The relationship is one-to-one. As you decrease the loft of a club by one degree, you reduce its bounce a degree at the same time. The bounce angle increases equal to the amount of any loft increase. A one or two degree change in loft will not cause a bounce or dig sole with today’s clubs. But if you are changing lofts on older more flatter-soled irons, bounce should be taken into account.

If you do change the loft more than two degrees on a club, sole grinding may be necessary to restore the sole angle to a more playable position. Changes in lie do not affect the bounce of a club in any manner.

Can you be sure that a club will not break during bending?

Even the most skilled repair professionals can occasionally break a club. Generally breakage is a result of some type of inconsistency in the metallurgy of the club. Cast clubs may have voids in their internal structure. These voids are effectively weak spots that when subjected to pressure from bending will often cause hosel breakage. In addition the club may not have been heat-treated properly and can be very brittle. The hosel of the iron may have been bored off-center resulting in inconsistent hosel wall thicknesses. Breakage can occur when bending pressure is applied to the thinner hosel area. None of these manufacturing inconsistencies can be identified prior to bending.

A properly manufactured club may be bent many times without breaking. There is no worry about bending a club that was bent last year or last week. It can be re-bent without any negative effect on it.

Are all bending machines accurate in their readings?

No, in fact all machines with fixed measuring gauges will not be accurate when measuring clubs with offset, progressive offset or face progression hosel positions. Machines that adjust for all hosel positions, such as Mitchell® Angle Machines are accurate regardless of the offset or hosel design of the golf club. Mitchell® machines are capable of bending and measuring clubs simultaneously.

What is Proper Club Head Registration?

Club head registration is the key element when bending or measuring clubs. Proper registration requires the club to be clamped securely in the bending machine with the face square and horizontal by positioning the club’s score lines parallel to a horizontal reference point. Score lines are manufactured into the club’s face parallel to the face attitude. The face attitude at impact is what directs the ball’s flight.

The club’s sole and its imaginary ground line have nothing to do with the attitude of the club’s face at impact. Measuring the club’s lie off the center of the club’s sole in a specification gauge is impossible to do accurately and it is impossible to repeat the measurement. Loft and lie angles are accurately measured from the club’s face attitude (horizontal score lines) to the shaft plane and are repeatable.

How much can a club be bent?

The common industry answer is “2 degrees.” This limit is only recommended when changing the lofts on irons due to the potential effect such bends will have on the sole angle of the club. If the hosel design and manufacturing processes allow, the lie of an iron can be bent 3-4 degrees or more with no compromise to the integrity of the head. This is especially true of clubs made with long hosels.

Practice on a few old irons in order to become comfortable in bending lie more than 2 degrees. It is easy to do in a machine that securely holds the club. Machines without adjustable sole clamps will often allow the iron to slip during bending, making the repair professional think the club bent when it didn’t.