Herstellung / Engl.

Manufacturing a Miura forged iron
By: Julian So

The process of manufacturing a Miura iron head begins with the selection of the finest soft steel suitable for the Miura forging process. Do not be fooled into thinking that the soft steel used for all golf clubs currently available in the market are the same. There are many grades of soft steel. This careful selection of raw material contributes significantly to the sense of feel and control a player experiences when he or she uses a Miura forged iron.

Each cylindrical stick of soft steel is first heated and struck with a forging hammer to mould it into the shape of an iron head. Thereafter, the excess metal is removed and the “raw iron head” is delivered to the Miura factory. While this rough “first forging” process is carried out at a another factory appointed by Miura, the type of soft steel used in the process is specially selected by Miura.

After the initial forging, the "raw iron heads" are brought to the Miura factory, where they undergo the Miura forging process. Each “raw iron head” is heated again and re-forged to further refine the iron head. At this stage, the molecular structure of the soft steel begins to re-align into a certain uniform lattice arrangement. This would refine the iron head fairly close to the finished product. In fact, many forged irons available in the market would follow-up with the finishing process here to produce the final product. However, for Miura, this is not sufficient.

At Miura's factory, the refined iron heads are re-heated again to red-hot temperatures using a special Miura heating technique. This technique not only heats up the irons heads to the desired temperature in seconds, but also ensures that carbon will not accumulate on the surface which would contaminate the soft steel composition. Each glowing red iron head is then forged for the third and final time using the unique Miura forging process. This process not only further refines the iron head but also further aligns the steel molecules into an extremely packed and uniformed fashion throughout the impact area, a complete transformation of the molecular structure of the initial raw material. This is why only selected grades of soft steel could be used. In fact, under 400 times magnification (using destructive testing methods), the difference between an iron head that has been through the third Miura forging
process and one that has not becomes undeniably clear. While not visible to the naked eye, golfers will still be able to tell the difference when they use a Miura forged iron.

This fine iron head will go on to allow a player to experience both a sense of softness and solidness when hitting the ball, which is unique to Miura forged irons. Through this incredible Miura precision forging process, it is possible to ensure that each finished Miura iron head has a weight error of not more than 0.5 grams, a reflection of Miura’s personal quest for perfection in quality control.

The number, name and score lines are then engraved onto each iron head and the hosel is welded onto each iron head using a special Miura spin welding process. This unique spin welding process allows precise adjustments to the angle of attachment, resulting in incredible precision in both the loft and lie characteristics of a Miura forged iron. Again a reflection of the extremely high standards and quality control implemented at the Miura factory.

Thereafter, expert grinders will make minute final adjustments of weight, finish and design to each iron head through precision grinding and polishing techniques. It should be noted here that all fundamental weight adjustments have already been completed during the forging process as described above (which is unique to the Miura precision forging process).

Miura is also very particular about aesthetics. Each finished iron head is polished by rotating it through a polishing barrel. Three different techniques, namely vibration, centrifugal and dry barrel polishing, allow three different looks to be achieved in the Miura iron heads. To complete the iron head, nickel chrome or W nickel (satin) plating is used on the face, while nickel plating, with copper additive, is used on the rest of the iron head. Through a unique Miura plating technique, the face of each iron head can be made to look "raw" and unpolished while the rest of the iron head plated, if desired.

Finally, grit is blasted onto the face of each iron head to provide additional grip on golf balls and colour is added to the stamping on each iron head prior to final inspection. During the Miura forging process, each iron head undergoes 11 separate inspections to ensure that each Miura forged iron is of nothing less than exceptional quality.

Knowing the exceptional quality of the Miura forged irons and the expense, effort and commitment put into manufacturing these excellent golf clubs, the Miura forged irons have become my most desired golf equipment. What about you?