The age-old question: should you buy forged or cast irons?
Is one somehow better than the other?
Here’s a great example of a myth being perpetuated as a fact. How does the elemental composition, on a molecular level, of an inanimate object affect its performance?
Let’s start off by looking at each type.
The Forged Iron
A forged iron is one made of carbon steel. Usually, a metal “billet” in the shape of a cylinder is placed into a die press and hammered into shape. Depending on the manufacturer, the head is formed separate from the hosel. In those instances, the hosel is later welded to the head. Like these:
To get it out of the way, no method is superior to the other.
It’s just a means to an end. Most of the “we’re better than so-and-so because we do <insert method here>” is purely marketing. Nothing more, nothing less.
The Cast Club
Manufacturers use what’s called the “Lost Wax” casting method. Here’s a non-golf video to explain how it works:
For those of you not interested in a little enlightening education (unfortunately, I’m not in the mood for education-shaming today), the stripped-down bullet-point definition is:
- a model is made of wax. In our case, a golf club head.
- A mixture (called a “slurry”) is applied to the model and allowed to harden.
- The unit is then heated up, so the wax melts out (lost wax… get it?), leaving a “negative” of the model.
- Molten metal (as it applies to us, stainless steel) is poured into the mold to form the clubhead. Check these out:
What’s the Diff Between Forged and Cast Irons?
Besides the obvious, what are the differences between the two types?
Why are forged irons more expensive than cast irons?
Are there any playability differences?
For starters, one is made of carbon steel and the other from stainless steel, but we’ll discuss that later.
Forged irons are more expensive than cast irons because it’s more expensive to make a finished head.
- The tooling is expensive to make and needs a high level of (costly) maintenance.
- There are many hand operations. The finished shape needs to be hand-ground, and the lofts/lies need to be manually adjusted, just to name a few.
- Because raw carbon steel is rust-prone, each head needs to be chrome-plated. In and of itself, a very costly process.
I worked in an automotive factory for a time that had a chrome-plating department. The headaches with that one part of the facility were many:
- Cost of the plating
- Regulations on usage and disposal (a real killer)
- Rejection/scrap rates
And more… it was a real nightmare.
This differentiates from cast clubs because the casting mold created can make many more heads compared to the forging dies before needing maintenance. There are the loft and lie adjustments and some polishing, but far fewer hand operations than the forging process mean a lower cost to the manufacturer to make.
Definitely no high-cost chrome-plating, either. The plating process is expensive as-is, and that’s not including the regulations, waste removal standards, and all the other rigamarole that goes into it.
Waitaminit… That Can’t Be All the Differences Between Forged or Cast Irons, Can It?
More or less.
It’s safe to assume everyone noticed I didn’t mention any playability differences. The reason for that is, there is none.
Keep in mind that no one is going to sell you clubs you can’t theoretically hit.
Doesn’t matter if it’s blades, cavity-backs, or whatever. If you’d have asked this 20+ years ago, the answer would be much different. Back then, blades were made very thin, much thinner than today’s blades (where the term “butterknife” as it refers to golf clubs comes from).
Not only that, they had much longer hosels. That extra weight in that area meant the Center of Gravity (CG) was pulled closer to the heel. A lot of people, assuming it should be in the center of the face, struggled with that kind of design.
That’s not the case anymore. Especially not with today’s more advanced methods of adjusting weight around the head to increase MOI. Weight plugs, the strategic use of heavier metals (like tungsten), thickening the topline and sole, and other ideas have brought these clubs a long way in the “easier to hit” department.
Get your clubs fitted, and the differences become even more minute. While you’re at it, get lessons, too.
But, Forged Irons are “Softer” Than Cast Irons!
Carbon steel is a little softer than stainless steel. While that’s true in a metallurgical sense, does it matter? Take a look at this, from Dave Tutelman:
During impact, both the ball and the clubhead compress. Consider the compression stiffness of each of the two materials:
- Force/deflection for the clubhead material is Kh.
- Force/deflection for the ball is Kb.
In an “elastic collision” like that of the ball and clubhead, the overall stiffness of the collision is:
1 Force/deflection overall =
1/Kb + 1/Kh
Of course, steel — any kind of steel — is much stiffer in compression than a golf ball. That is, Kh is greater than Kb, by a factor somewhere between a hundred and a thousand. Let’s assume it’s 100, just to give the greatest possible chance to show that clubhead material does matter. Even with this assumption, a few examples will show us that the stiffness of the collision is dominated by the ball’s construction, not the clubhead’s.
From the softest steel to the hardest, the range of Kh is only a 10% range. Suppose forged carbon steel were a full 10% softer than cast stainless. Then wouldn’t the collision feel 10% softer? No, it wouldn’t. From the equation, a 10% reduction in Kh results in only a 0.2% reduction in overall stiffness of the collision.
Well then, let’s choose a really soft metal like copper, and use it as an insert. (As I write this, such a set of irons has appeared on the market.) Even copper, at only half the stiffness of steel, results in only a 1.0% reduction in the overall stiffness of the collision. Not even the most practiced pro could feel this; even if he/she could, ball-to-ball variation is considerably greater than this.
Finally, suppose we reduced the ball’s compression by 10%. This time, the collision is in fact 10% softer. So the compressibility of the ball dominates the feel of the collision.
I mean, are we for real? If we were talking about a five iron made of plastic and another made of metal, the differences would be painfully obvious. But we’re talking about two different forms of steel. Steel!
Would a crescent wrench made of carbon steel turn a nut “better” than one made of stainless steel? If you weren’t told the difference, would you even notice?
I don’t know if people like these “real world” comparisons, but they hold water. Think about it: golf clubs aren’t some magical device that somehow defies the laws of physics (or common sense)… they’re tools used to play a game. That’s it, but it doesn’t stop there.
Now you might be thinking: “What the hell, man, when I strike a forged club poorly it doesn’t go as far and flies sideways!”. Hold your horses and keep reading…
My Forged Iron Has <insert country of origin here> Carbon Steel, So It’s Better Than Those “Other” Carbon Steels
Not even close! Check this out, from Tom Wishon (via GolfWRX):
Chemical Composition of 1020 Carbon Steel
Chemical Composition of 1030 Carbon Steel
Not much of a difference, is it? Regardless of where the metal originated, they all have standards they have to abide by… and they’re all pretty close together in amounts. Definitely not enough for us to really notice.
My forged blade plays differently (better) than those hacker cavity-backs… right?
Not really, no.
There was an iron model, well, two models, released in 2007 that were different from the normal kinds of releases.
You see, most forged models are intentionally made and marketed to cater to the “players”.
These were released simultaneously; one was forged, one was cast. There were some slight cosmetic differences and a whopping 2* difference in loft angles. It should be noted that it takes a 4* difference to be able to perceive a distance change (one reason why most irons are 4* apart from one another).
Needless to say, one didn’t perform better than the other… and we’ve never seen an iron release similar to that as of this writing.
Don’t get me wrong; if you have a blade style with a thin sole and even thinner topline, it’ll perform differently from a CB model that has a thick topline and even thicker sole (assuming all other specs are the same). Misses away from the “sweet spot” would be noticeably different. However, if you made the blade’s topline and sole super thick and the CB had the razor-thin sole and topline, the blade would be noticeably better on miss-hits.
In essence, if you made the exact same club but cast one and forged the other, you’d never notice which is which unless you were told.
So How Does All This Explain The “Feel Effect”?
If you were to test a forged model and a totally different cast model against one another, of course there’d be differences, even in “feel”. They’re two totally different clubs!
Where the differences are biggest in the shape of the club. Many forged irons are made in the “blade” style, while pretty much all cast irons are made in the “cavity back” style. There’s more metal behind the “sweet spot” in a blade than in a CB.
In his book The Complete Golf Club Fitting Plan, Ralph Maltby discusses the “forged v. cast” myth (p. 42):
“(T)here have been a number of tests conducted where identical twin sets of forged and cast irons have been made up and compared by golf professionals, low handicap amateurs, and others. They hit shots with each type and were asked if they could feel or notice any differences. The results showed conclusively that in identically designed heads not even the finest players in the world could tell any differences”.
As club builders, we can do things to affect the “feel”, regardless whether it’s a forged or cast iron:
- Changes to the swing weight (or MOI),
- A change in shaft weight (which will also affect swing weight in many cases),
- Adding “ProSoft”/Sensicore inserts in the grip end, or wooden dowels in the tip end,
- Change the shaft flex and/or torque (for those with a late release),
- Switching to a softer-covered ball (usually, going from a Surlyn-covered ball to a urethane model)
What Am I Supposed To Do NOW?!
Simple. Get what pleases you.
If you want a forged, blade-style iron, get it.
If you’re happier with a cast, cavity back-style iron, get it.
In the grand scheme of things, it only matters to the one spending their hard-earned money. Yes, I mean you. Just remember that whatever you decide on, get fitted for your new sticks!