The story on Development of MG701 3 Going for the Ideal Face Thickness
Three years ago, someone in charge of materials at a U.S. steel company visited the Sakata Plant. He introduced a newly developed, high-strength stainless steel to Suwa and his team. However, the prevailing view at Honma at the time was that iron clubs should be made of highly flexible iron materials that produce a good feel when the ball is struck. So the new material was put on the shelf.
Then, down the road, the day came when Suwa contacted steel company. Three years later, they had come with an even stronger material. He then requested that a prototype be made with this new material, marking Honma’s first real shift to stainless steel after many years of remaining loyal to soft iron.
But the question remained: Why the change from soft iron to stainless steel for irons anyway?
Stainless steel is a material made by mixing nickel or chrome with iron. It is less prone to rust than iron, and it is heat and cold-resistant. In addition, it can be created thinner than iron due to its strength. And the thinner the material, the higher the restitution.
The harder the head, the more excess power is placed on the ball at impact, which can keep the ball from flying at its optimal best. This creates loss of energy, giving rise to spin and hindering carry.
If the head has flexure, on the other hand, it absorbs the power placed on the ball, energy is distributed, and there is a synergistic effect which packs the ball flying. This is the same principle utilized by smash hitters in tennis, who intentionally keep the gut on their rackets loose. It is also the same principle as the urethane-wrapped bats used in softball to engender distance.
Soft iron is difficult to render thin compared to stainless steel. In addition to the resultant limitations on flexure, this means that a certain strength level is required to send the ball flying. However, there are many golfers who prefer the unique feel of the soft irons. For these individuals, the Beres line includes the BERES TW901 iron, which is designed for pro athletes.
Working together with steel company, Sakata Plant introduced a number of improvements to create prototypes that we hoped would pass the strike tests. We came up with 1.8, 1.9, 2.0, 2.1, and 2.2 mm iron heads. Tested at a head speed of 40 m/second, the 1.8 exhibited the best carry, but tended to be inconsistent. The next best carry was produced by the 1.9 mm, and this face was more consistent. The 2.0 models and up did not perform as well carry-wise.
The development team concluded that the 1.9 mm was the ideal face for the average golfer.