At the launch of Mizuno latest range of products including the MP-18 irons, S18 wedges and CLK hybrids, I caught up with Director of R&D, David Llewellyn, to find out about the technology behind the new clubs.
Hi David. You’re launching the MP-18 irons today, so what is unique about this range?
Well the MP-18 is really a family of irons. We have the MP-18 Muscleback, the MP-18 Split Cavity and the MP-18 Multi-Material Construction iron. The way the family was designed is that each one is a great stand-alone iron set, but also we encourage people to mix and match, whether you want the muscle back scoring irons, split cavity middle irons or multi-material long irons, you can build whatever level of playability you require into your set and have a very consistent look, a very consistent feel, a very consistent performance from long irons through scoring irons.
So you’ve got four sets here. Is there any reason you have four separate sets rather than one or two sets that are blended?
That’s a fair question. I actually consider it to be three and a half sets because we have the three full iron sets and then we have what is called the MP-18 Multi Material Fli-Hi which is a hollow, long iron type hybrid which has speed of the face and ease of launch, but it is still in a small, thin top line, less offset package, so it really speaks to that better player, that MP player, and those are just long iron replacements.
So if you want to build even more playability, launch and speed at the long side of the set, maybe adding a 2 iron, or replacing a 3 or a 4 iron, you can really add a lot of playability and maintain those distance gaps on the long side of the set.
So when you are going from the blade to the SC and then up to the MMC, what are the main differences between them? Is it launch or is it forgiveness or is it something else?
Within the MP-18 family we have three different levels of head size and MOI starting with the Muscleback which is the smallest head and is going to be the most workable and least forgiving. At the other end of the spectrum we that the Multi-Material Construction (MMC) head that is a little bit bigger, a little bit more offset, still a very compact head but it has a surprising level of playability because of the 20g of tungsten that has been embedded low and on the toe side which expands the sweet area in a smaller package.
The MMC also has the titanium and this is unique to Mizuno where we take a forged piece of titanium and forge it into the forged head, so everything is forged but that titanium behind impact allows us to expand out the sweet area even further whilst still maintaining the thickness behind impact so you get that really solid feel with a surprising amount of playability. And of course we have the Split Cavity irons in the middle so they offer three different levels of playability.
How would you suggest golfers go about mixing and matching the irons into a set if they wanted to do that?
I think it really comes down to the personal preference in terms of mid irons and short irons. Some people really like the look of a muscle back, some people like to have that little bit of comfort level with a shallow cavity design, or the multi-material design so really that comes down to preference.
On the long iron side, every player has a threshold where they have enough club head speed and the right angle of attack to generate the appropriate launch angle to maintain distance gaps. So for somebody like myself, I need help somewhere around the 4 or the 5 iron. Even though I prefer the look of a muscle-back by the time I get to the 5 iron I might want to do a SC in the 5 and 6 iron and then the 4 iron I need a little more help with launch which is where the MP-18 MMC and MMC Fli-Hi’s come in.
They are very MP, they are nice and compact, they have a hollow body construction with a thin maraging face, they also have 20g of tungsten to expand out the sweet area but still with the thin top line and a minimal offset so I would probably put those in the bag for the 3 and the 4 irons. That means I have the launch and speed on the long iron side, the mid-irons have that little bit of forgiveness built in and then 7-PW I am looking at what I love which is a classic muscle-back.
In terms of material I know you have been using the Boron Steel lately, but with the MP-18 irons you have a slightly different kind of steel. Can you explain what that is and why perhaps you haven’t gone down the Boron route?
Sure. What we did was take a couple of years off from launching an MP iron for a couple of reasons. Number one, we were working on an improved version of the Grain Flow Forging process. Also we are kind of resetting MP, getting back to the roots of MP in terms of who it appeals to, head size, how it looks, building timeless classics in terms of the aesthetics. One of the keys behind all of that was the new forging process which we call Grain Flow Forged HD and the HD stand for High Density.
At the heart of it is still Grain Flow Forging but what we have been able to do working with our exclusive forging vendor in Hiroshima, Japan, is we have changed the mould design ever so slightly where we are able to actually capture more grains of the metal behind impact, and they are very tightly compacted high density grains behind impact.
So with Grain Flow Forging we already had some of the most recognised irons in terms of feel in the market and we have now added this on top of it and what that does is it actually offers more feel, more feedback and the sensation that the ball is on the face longer. Sometimes you hear with a really good forged iron that players can feel the ball compress on the face and that sensation is accentuated in these irons.
So does the denser material give a more solid feel or is it to do with sound and how does it benefit the golfer?
Good question and there a couple of answers to that. We call it High Density but it is still the same density of steel it is more the higher density in terms of the number of grains of the metal. So just like wood has a grain structure to it, so does metal. The goal with the forged iron is you want the long continuous grains which are tightly compacted.
It is very similar to if you are choosing a nice piece of wood to build a baseball bat or a cricket bat where you want the tight grains – so it is more the density of the grains rather than the density of the material itself. That is where the feel comes from. If you can have those long dense tightly compacted grains the head actually vibrates longer and that is the sound we are talking about. The sound of impact you actually hear that moment a fraction of a second longer which gives the sensation of feeling softer or feeling the ball compress.
In terms of the looks of the MP-18 irons I know you have gone back to the original designers of earlier MP irons. How much do aesthetics play a part in getting the club off the shelf and sold?
Well we think it is a huge part and we also appreciate the fact that there is all different kinds of golfers out there. We have the wonderful JPX900 line and the design philosophy behind that is aggressive, speed, futuristic and a lot of people really love that.
Then there is the MP which is more timeless and sophisticated and clean and minimalistic. We actually made the MP-18 what we call a “white out” so the logo is very subtle, we only used white paint, a very light satin brushed chrome finish to keep everything very sophisticated and clean.
We have also got the S18 wedge here that is replacing the S5. What are the differences between this and the previous model?
One of the first things we worked on was the shaping of the head and the T7, T meaning “tear-drop”, had a lot of straight lines to it, a very classical tear-drop shape. The S5 wedge we called “silhouette” with a more rounded shape, so with the S18 we really wanted something that was right in the middle.
So it has a little bit of a round aspect to it, a little bit of a tear-drop aspect to it, but even within that, for each loft we have dialled in a precise head shape so your gap-wedge or your specialist pitching wedge is going to have the straighter lines because it is more built for a full swing where you want to square it up a bit better. As you transition down to the lob wedge it is getting a more rounded profile as we wanted to design the head shape specific to the function of that wedge or what it is primarily used for.
I noticed compared to the S5 wedge that there is more grind around the heel and the toe area. Is that through the whole range or is that just for certain lofts?
That’s a good observation. What we did on the higher lofts, starting at the 56 and through to the 60 is to include a bounce specific grind. So your higher bounce wedges actually have a little bit less taken off the toe and the heel as the player who needs the higher bounce might be a little bit steep coming in and needs the bounce to get the club in and out of the turf. With the lower bounce wedges we put a more aggressive grind on to make those clubs even more versatile.
In the S18 we have also built in a loft specific centre of gravity location. So with the higher lofts we have put quite a bit of weight at the top of the blade and what that does is move the centre of gravity up the face so as you are getting more loft the centre of gravity is getting higher.
That is doing a couple of things for you. It firstly increases spin and secondly it increases vertical MOI which is necessary as when you are in fluffy grass you tend to hit the ball higher up the face. By adding this extra mass higher up the face it increases the consistency of speed of the face for all shots.
Have you achieved that just with weight at the top of the head or have you adjusted hosel length as well?
No it is a pretty standard hosel length. Ours tends to be a little longer than industry standard and the hosel also helps bring the centre of gravity up as well.
Finally we go to the other end of the bag where we have the new CLK Hybrids which are replacing quite a range of hybrids.
Yes. We made a strategic decision to take the hybrids out of the metal woods world and make them more stand alone. We did this for a couple of reasons. Firstly we think the hybrid is a natural add on to an iron set, so it is something we can really get behind in terms of custom fitting and integrate into our software.
Secondly we were talking about thresholds in terms of speed and launch where you might want to use the Fli-Hi’s and it is very similar for the hybrid. Players will reach this threshold where you start to need help in terms of launch and ball speed to maintain distance gaps and that is what the CLK hybrid does extremely well.
We have a couple of technologies going on in the CLK. We have a maraging face that we are able to get very thin for high ball speeds but to add to that we have the new Shockwave technology. This has a very aggressive high amplitude first wave giving the club an accordion effect with even more ball speed, particularly centre to low on the face which is a typical impact area when players are hitting there hybrids from the turf.
We also did a lot of work on the head shape as well to give it very clean lines, very sophisticated looking and make it very easy to square up. We have also continued using the quick switch hosel in the CLK.
The club comes in 16, 19, 22 and 25 degree models but the quick switch means from there they can all be adjusted plus or minus 2 degrees meaning that we can hit any loft from 14 degrees all the way up to 27 degrees and that really helps when you are adding these to a set of irons to fit the distance gaps between your longest iron and your fairway wood.
So with the new Shockwave sole channel how much extra ball speed are you getting say compared to the JPX900?
We are seeing a couple of miles per hour actually and we designed it not only for the higher ball speed but it also knocks the spin off by about 500 to 600 rpm. So 19 degree to 19 degree compared to the JPX900 we are seeing about a half a club gain with the CLK.
How have you managed the turf interaction with the deeper channel as this has been an issue on other hybrids that have done this?
We did extensive player testing to make sure we didn’t have a problem and I think the key for us is the shape of the front edge, making sure it is blunted off and making sure that the wave feature is completely recessed so it is almost like it is not there as it goes across the turf.
One thing I did notice that surprised me was the 16 degree had the deepest head and the 25 degree had the narrowest head front to back when I would maybe have expected it the other way around. Can you explain why that is?
Well if you make the head deep on the 16 degree that is going to pull the centre of gravity back more and that is going to provide launch. So as you get higher in loft up to the 22 and 25 degree models you don’t quite need that deep centre of gravity to provide the launch so we can make the head a little bit narrower it helps to flight the ball down a little bit.
Thank you for taking us through the new products David.
Mizuno MP-18 irons review
Mizuno S5 wedge review
Mizuno CLK hybrid review
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