Appendix II, 1d states that:
| When the club is in its normal address position the shaft must be so aligned that:
(i) the projection of the straight part of the shaft on to the vertical plane through the toe and heel must diverge from the vertical by at least ten degrees. If the overall design of the club is such that the player can effectively use the club in a vertical or close-to-vertical position, the shaft may be required to diverge from the vertical in this plane by as much as 25 degrees;
(ii) the projection of the straight part of the shaft on to the vertical plane along the intended line of play must not diverge from the vertical by more than 20 degrees forwards or 10 degrees backwards.
This Rule is particularly relevant to putters and it exists mainly as a means for disallowing croquet style putters (with vertical shafts) and shuffle-board style strokes (see Figure 4). It also seeks to limit the potential for more standard putters from being used effectively in a vertical or near-vertical position using a pendulum-style motion.
For most putters, the “normal address position” is determined by the geometry of the head. The head would be placed on a horizontal flat surface, with the sole touching that surface at a point directly below the centre of the face. The shaft angle would then be measured with the head in this position (see Figure 5).
Fig. 5 - Measuring the angle of a putter shaft
If the putter head shape or weight distribution is very asymmetric, it may be necessary to make a subjective judgement as to where the effective centre of the face is and then to sole the club directly below that point. The position of the head in this instance might not always be the position that was intended when the club was designed, but in some cases a judgement has to be made based on how the club could feasibly and effectively be used (see Figure 6).
Fig. 6 - Club with asymmetric sole
The same subjectivity may also be needed when confronted with a putter which has a very curved sole (see Figure 7). As before, the conformance evaluation would take into account not only the manner in which the putter is designed to be used, but also the way it could feasibly and effectively be used, given the geometry of the head as well as other unique characteristics of the overall design. This interpretation is particularly relevant to long-shafted putters with very curved or multi-planed soles – but standard length putters of 34-38 inches can also be subjected to this assessment.
Fig. 7 - Putter with very curved sole
It should be remembered that all putters can usually be positioned in such a way that the shaft diverges from the vertical by less than 10° or even to a position where the shaft itself is vertical. Also, it is unusual for the sole of a putter to be completely flat all the way from heel to toe. When faced with a ruling of this kind, the decision should not be based on whether a player uses the putter with the shaft in a position less than 10° – but whether the putter design facilitates this (see Figure 8).
Fig. 8 - Putter with curved sole
If the overall design of a putter is such that the player can putt effectively with the shaft in a vertical or near-vertical position, it would be ruled contrary to Appendix II, 1d, even if the shaft angle does satisfy the 10 degree Rule when the putter is in its “normal address position”. The shaft on such a putter would be required to be increased up to as much as 25 degrees. In assessing whether a putter can be used effectively in such a position and in order to determine what the shaft angle should be increased to, the combination of all of the following features must be considered:
length of shaft;
position of shaft attachment to head;
angle of shaft in toe to heel plane and front to back plane;
shape and weight distribution of head;
curvature and shape of sole; and
intent of the design.
This means that a long putter which has the shaft attached to the toe, a 10 degree lie angle in the toe to heel plane and a curved sole could potentially be ruled non-conforming. Even though each of these features, when taken in isolation, might conform to the Rules, it is the combination of these features which could lead to a non-conforming decision.
This is a good example of an area where Tournament Officials should take care not to make decisions unless they are completely certain that it is correct. If, after examining the club and carrying out all of the appropriate consultations, it is still not possible to give a definitive ruling, a Duration of Competition or Duration of Round Answer should be given (see Supplementary Paper A – Advice to Rules Officials Concerning Queries on the Conformity of Clubs at Competitions).
The determination of a putter’s “normal address position” or whether it can be used in a vertical or close-to-vertical position can be highly subjective and in terms of those putters which are actually submitted to The R&A, the job of making rulings on them is only made easier because it is possible to compare them with previous submissions and rulings.
Appendix II, 1d goes on to state that:
| Except for putters, all of the heel portion of the club must lie within 0.625 inches (15.88mm) of the plane containing the axis of the straight part of the shaft and the intended (horizontal) line of play.
The intent of the Rule is to prevent centre shafted clubs (see Section 5-"Attachment to the Clubhead"), and the measurement of an iron club is illustrated in Figure 9.
It is worth highlighting that the heel portion of the club extends from the face all the way to the back of the head. Therefore, for unusually shaped heads (e.g. flared or square shaped), where the outermost part of the heel may be further back from the face than for more traditionally shaped heads, the measurement will be completed at that point.
Fig. 9 - Shaft axis/heel measurement
It is also worth stressing that, in most cases, the shaft of a putter may be attached at any point on the clubhead (see Section 6 - Attachment to Clubhead).