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Mizuno MP-18 line offers a new take on forging and iron set makeup

August 07, 2017

The new Mizuno MP-18 might be seen as one new iron from one of the leading forged iron companies in the history of golf. Or it might be seen as three new irons, maybe even four.

Or quite simply it could be seen as any number of new iron sets because the Mizuno MP-18 blade, its split cavity brother the MP-18 SC, the fraternal twin, titanium-and-tungsten-infused MP-18 MMC, as well as the hollow, fast-faced MP-18 FLI HI, are all so many linked pieces of one offering.

“We want you to see this not as three different irons sets but one iron set with three different versions and all one big family,” said Chris Voshall, golf club engineer at Mizuno. “All were designed to mix and match.

“How you put your set together is becoming a huge thing now for players at this level and really any level.”

The company, by way of its Performance Fitting System software, literally is automatically recommending mixed sets more and more often these days, and that will be especially the case with the Mizuno MP-18 line.


At the foundation is the MP-18, a forged blade conceived through Mizuno’s unique collaboration between high-tech, three-dimensional digital design and precise input of the old school craftsman in Yoro, Japan, a process that adds about a month and a half to the normal iron development cycle.

“What that allows us to do is get the shaping perfect, as smooth as we need it to be and have the proper flow,” Voshall said. “It’s not something that you can dial in as freely when everything is hard dimensions like it is in the 3D world.”

What the craftsman and the engineers have produced is ultimately a new kind of forged iron that still embodies Mizuno’s classic, time-proven shapes. What’s new about is the forging process, what the company has called for nearly two decades “grain-flow” forging. In that process, a billet of 1025E carbon steel is stretched into an angle that matches up with the hosel and clubhead shape. The new process reduces the excess material outside the perimeter of the forged clubhead, concentrating more density in the hitting area to improve feel. The company is calling the new process “grain flow forging HD,” for “high density.”

“By having this very uniform flash material around it, that shows we’re capturing long uniform grains in the middle, grains aren’t being cut off,” said Mizuno’s David Llewellyn, manager of research and development. “The material is actually flowing out of the mold very uniformly. So that’s the grain continuity that leads to longer vibration and better feel.”

The MP-18, a traditional muscleback blade, will feature a microscopically wider sole compared to the MP-4 and a smaller head size than the MP-5, especially in the short irons (“It’s the smallest pitching wedge, 9-iron, 8-iron, 7-iron we’ve ever done,” Voshall said.)

While Voshall calls the MP-18 more forgiving than past Mizuno blades, he happily points to three other more forgiving choices in the MP-18 family as options for mid and long irons. Those include the two full sets of their own (MP-18SC and MP-18MMC), as well as a collection of hollow utility irons (MP-18 FLI HI).


The MP-18 SC is a similarly manufactured forging that features a low-muscleback with an upper cavity through the set, but is made to match up nearly identically to the MP-18 blade. Only slightly wider in the sole, the offsets and trailing and leading edge radii are the same for similar action through the turf.

The most technologically sophisticated member of the family is the MP-18 MMC, which combines titanium forged into the carbon steel (no welding) with tungsten weighting in the toe section of the mid- and long irons for expanded forgiveness. The 20-gram tungsten plug fits in an internal cavity that allows it to rest deeper as lofts get lower (and soles get wider) to increase forgiveness progressively. The use of a lightweight titanium bar fills a centralized cavity like a muscleback, saving weight while maintaining feel.


The final piece of the MP-18 line, the MP-18 FLI HI, mixes a bendable X-30 cast steel body framing a high-strength HT1770 steel face insert. The combination aims to produce a more flexible face with a lower center of gravity for higher flight and more distance. The MP-18 FLI HI is available in 2- through 6-iron lofts.

The MP-18 and MP-18 SC are offered in 3-iron through pitching wedge, while the MP-18 MMC comes in slightly stronger lofts (4-iron through pitching wedge). Each MP-18 iron is $150 per club. The MP-18 FLI HI (16.5, 19, 22, 25 and 28 degrees) will retail at $150 per club. The full MP-18 line will be in stores in September.