The R&A
St Andrews, Fife
Scotland KY16 9JD
Tel: +44 (0) 1334 460000
Fax: +44 (0) 1334 460152
www.randa.org
www.opengolf.com

28 May 2008
NOTICE TO MANUFACTURERS

PROPOSED REVISION OF INTERPRETATION AND EVALUATION OF SPRING FEATURES WITHIN
CLUBHEADSIn November 2004, The R&A issued a Notice to all manufacturers clarifying its interpretation
and application of Appendix II, 5a of the Rules of Golf in respect of ‘spring-like effect’. This
Notice stated that, whilst the conformance of a club to the Pendulum test was necessary,
this test was not sufficient to assess every design with regard to the intent of the Rule.
Therefore, designs which include features that are intended to act like a spring,independent of the level of flexibility achieved by the design, would be ruled nonconforming.
Since that time, a number of clubheads have been found to have features which arecontrary to the intent of this Rule and, whilst some of these clubs may not have exceeded
the limit for ‘spring-like’ effect as measured by the Pendulum Test, they were deemed topossess features which have the characteristics of springs and as such were determined to
be non-conforming.
Since January 2008, the language contained within the Rules of Golf has been revised toreflect more accurately our interpretation of ‘spring effect’. Appendix II, 4c now statesthat:
Spring Effect and Dynamic Properties
The design, material and/or construction of, or any treatment to, the clubhead(which includes the club face) must not:
(i)
(ii)
(iii)

have the effect of a spring which exceeds the limit set forth in the Pendulum
Test Protocol on file with The R&A; orincorporate features or technology including, but not limited to, separate
springs or spring features, that have the intent of, or the effect of, unduly
influencing the clubhead’s spring effect; orunduly influence the movement of the ball.

Having now expanded the wording of this Rule to ensure that its intent is not circumvented,
the purpose of this Notice is to propose a new test method which will provide clarity andcertainty to both the Governing Bodies and manufacturers in evaluating theThe R&A
St Andrews, Fife
Scotland KY16 9JD
Tel: +44 (0) 1334 460000
Fax: +44 (0) 1334 460152
www.randa.org
www.opengolf.com

conformance of future clubhead designs to all aspects of the revised rule. If adopted, this
proposal would mean that a submitted club would be evaluated solely based on its
performance on the Pendulum (as described below) rather than by evaluating the designand construction of the club in other ways.
Currently, the Pendulum test is used to determine the conformance status of a club toclause (i) of the Rule – that is, to measure the flexibility or characteristic time (CT) of theclub at the centre of the clubface against the limit of 239 microseconds, plus tolerance of
18 microseconds. It is proposed that the use of the Pendulum is extended to determine
also whether a design unduly influences the clubhead’s spring effect (clause (ii) of theRule) by requiring that the CT of a club does not exceed the same limit for the centre of
the clubface at any place on the clubface.
Exact locations for any additional measurements on the clubface will not be specified,rather, The R&A will reserve the right to test the clubface at any location.
At this time, it is intended that this proposed new test will apply to driving clubs only.
However, if other clubs are developed with similar spring features, this evaluation method
may be applied to them as well.
A clubhead whose design includes obvious springs, such as coiled springs or other similarfeatures, will continue to be considered non-conforming due to plain in shaperequirements and/or the requirement that all parts must be firmly fixed. As with all new
design concepts, manufacturers are strongly encouraged to communicate with The R&A
as early in the development process as possible.
If adopted, it is proposed that The R&A will implement this new measurement method
shortly after the conclusion of the Notice period. The R&A does not intend to re-evaluate
any previous submissions based on this proposed new measurement method. Any
manufacturer wishing to have a previous ruling re-appraised should contact The R&A in
writing, quoting the original decision reference number.
Written comments on this proposal should be sent to The R&A, marked for the attention of
Dr Steve Otto, Director – Research & Testing, The R&A, St Andrews, Fife, KY16 9JD, Scotlandor by email to steveotto@randa.org. These comments should arrive in St Andrews before 1
July 2008.