Understanding Putters: Head Weights, Swingweights, and Correlation to Green Speed

November 19, 2012

Today we’re going to talk about weight. No, I won’t be telling you how unhealthy you are and how you need to work out. Rather, we’ll talk about weight as it relates to putters and how different weights affect the putting stroke.

In golf, there are two types of “weight”–actual weight (which is usually measured in grams) and swingweight (which is not really a weight but more-so a balance of weight). Both are important to putting, although personal theories vary about how much importance should be placed on one over the other.

Swingweight is simply a measure of balance of weight from the grip, shaft, and head of a putter–or any golf club for that matter. If a club has a light total weight, but 70% of its weight is in the head, then the club will feel relatively heavy and have a high swing weight. However, if a club is relatively heavy but has only 30% of its weight in the head, it will feel relatively light and have a low swing weight. As such, swingweight really tells you only about the balance of weight in the club, not the total weight. For putting, some commenters believe that swingweight is an important aspect. While it does play some role in how a putter feels, I have always felt that it is of relatively little importance because the hands do not hing in a putting stroke. If you have trouble preventing your hands from hinging, you may seek out a putter with a higher swingweight to try and make it more difficult for you to force the putter forward. However, it is unlikely that simply balancing the weight differently (i.e., by getting a lighter shaft and grip) will result in any material change.

The far more important feature is head weight. Head weight is exactly what it sounds–how much the putter head weighs without the shaft or grip attached. Putter head weight is typically measured in grams, and most technical spec sheets will say to the gram how much the head weight might be. Most production model putters are 330 or 335 grams. I say “most” because some recent models, such as the Odyssey Black series and some newer Scotty Cameron putters, actually have varying weights for varying lengths. This is an attempt by the putter maker to keep a consistent swingweight regardless of the putter length. Because one inch of shaft length is about the same (for swingweighting) as adding 10 grams of head weight, you will see that many putters now have a 10 gram relationship per inch of shaft length. Scotty Cameron’s 2010 models include interchangeable weights. 35 inch putters are 330g; 34 inch putters are 340g; 33 inch putters are 350g. Obviously, some putter manufacturers believe that swingweight is important, and they try to keep this consistent among the series.

However, how Scotty Cameron believes a putter should feel should not dictate what you like. Many players today are opting for heavier putter heads in general, realizing some of the benefits that “heavy” provides. What is “heavier?” Well, that’s up to you.

For starters, the standard for smaller, custom-made putter heads has risen to 350g. Most players using Sunset Beach, Kari Lajosi, Byron Morgan, Tom Slighter, and a host of other “custom” putter manufacturer’s models are opting for 350g as stock weight. In addition, many putter makers are going even heavier. Piretti offers putters heads at 370g stock weight, and LaMont Mann customs go upwards of 400g on occasion.

The trend in increased head weight can be attributed to a number of factors. Most notably, better greens mean faster greens, and faster greens need higher head weight.

wait…what did he say?

You read that right. Fast greens need heavier putters.

Many people don’t understand this. They inherently think that if a putter is heavier, it will automatically force a ball harder because of “conservation of momentum.” Well, first, there’s not really such a thing as conservation of momentum. But, even if you have a hard time following that, here’s how it works–there are two explanations; one is scientific, one is not. Either way, I think you can understand. But since I have an engineering degree, I’ll start with the science.

First, force is equal to mass times acceleration. Look up Sir Isaac Newton for more reading.

F=m * A

Next, kinetic energy of any object in motion is equal to one-half of the object’s mass multiplied by the square speed the object is traveling. See Newton, again, for reference.

E= 1/2 m * V^2

Energy must be conserved at all times, so the amount of kinetic energy the putter head travels with will be very important for determining how hard you hit the ball at impact.

so here’s how it works. Most people, mistakenly thinking that higher weight leads to a harder hit on a putter, believe that they will accelerate the putter with the same acceleration regardless of how heavy the putter is. Well, let’s try this out. Take a wiffle ball bat and try to swing it. Now take a cinder block and try to swing it the same speed. The amount of force you have to put in to accelerate the objects the same way is so great that it’s virtually impossible to do. Of course, this is an exaggeration to show the point, but it works the same with smaller differences in weight as well. Simply put, it is very difficult to change your force input on a putter to achieve consistent acceleration regardless of the weight.

So if acceleration isn’t constant, then what is? If we assume that force the user imparts on the club is the same from one stroke to another (which is much easier to accomplish), then a heavier putter head will lead to less acceleration (see F=m*a). If there’s less acceleration–and we’re starting from a still position, which we are in golf–then there is less velocity. Because velocity goes down, energy goes down (see E=0.5*m*V^2), but the energy goes down at a proportion squared to the decrease in velocity. Now, because we have higher mass, the energy will go up per the increased mass, but it only goes up directly with the increase in mass. In other words, velocity is much more important since any change in velocity will have a squared result on the energy. Thus, the increase in mass is easily negated by the decrease in velocity. This leads to less energy at impact, resulting in a slower ball speed coming off of the putter face.

science explanation over

For those who skipped below, the second (easier to understand) answer is that a heavier putter head is simply more difficult to move, which is what you want with a fast green. Fast greens require very small putting strokes to keep the ball from getting away from you. It is much easier to make small movements accurately with heavy weight, as lighter weight tends to float around and get jerky.

As such, the trend toward heavier weight has a lot to do with modern greenskeeping making even the local muni course run at speeds that would be tour-caliber just two decades ago.

As with all other sections we’ve described, it is very important that you don’t lock yourself into thinking that one weight is good and another is bad just because someone else says so. You must play with the equipment that gives you the best chance to play good golf. Mark O’Meara recently had a putter made that was 315 grams, an absurdly light weight by today’s standards. Why? His old PING Anser putter that he grew up with was right around that weight, and he felt most confident that he could make putts with that weight. That’s a full 35 grams difference (3.5 swingweight points for those that were paying attention) away from what I play, but if it helps him make putts, it’s the right move.

What this section is meant to show you is twofold. First, you must know that there are other options out there besides what you might see in a big box store. Take some time to test out different options. You might really like that new Scotty Cameron, but it might be that the only reason it feels so good is that it’s so much heavier than everything else on the rack (some new 2012 Scotty Camerons are as much as 360g head weight!). Even with your own putter, you can experiment by adding lead tape to increase the head weight. If the other specs of your putter are properly fit (as we’ve been discussing throughout this series), then you should be able to dial in the head weight without much fanfare.

However, the second point is that you should find weights that work for you, but be willing to mix it up if the green speed is dramatically different. I recently played on greens that ran upwards of 15 on the stimpmeter. I wish I had had a little extra lead tape in my bag to help me slow down the putter head for those greens. Similarly, when I play a particular muni down the street from my house, I always bring a back-up putter that’s a good 15 grams lighter than my current putter so that I can properly hit through the shaggy greens on the course.

Now, you may find you play better on slow greens with a heavier putter and vice versa for fast greens. If that’s the case, go with it, and understand that that is your game. This post, however, shows you the reason for the common knowledge as it stands today.


13 Responses to “Understanding Putters: Head Weights, Swingweights, and Correlation to Green Speed”

  1. AJ Says:

    Great article!

    Thank you.

  2. Essarr Says:

    A most sensible and thought provoking article I’ve read in years on any golf equipment..! Thank you.

  3. Koz Says:

    Excellent article

  4. Ted McClain Says:

    What happens when you put more weight in toe of your putter, 20 grams and say 10 grams in the heel or vice/versa.

    • JK Says:

      you may move the center of gravity, but it’s unlikely to have a serious impact one way or another. for a 350 gram putter head, 10 grams represents 2.85% of the weight of the putter. So, the imbalanced weight would have 1/35th of the impact on the CG of the putter head. If you were to put the 10 grams a full 2 inches away from the sweet spot of the putter, the 10 grams would move the center of gravity about 1/20th of an inch–or about 1 mm. While it would affect toe hang and balance, the misbalancing would not be significant in my opinion.

  5. Rehan ashraf Says:

    Great article. I recently put super stroke 17 inches grip on my 34 inch scotty cameron putter. Since i put this grip my putter head feels lighter coz of heavier grip. So some one says to me change putter head weights . Before i had two 10g weights in my putter head , i replaced them with two 35g weights. Since then my putter feels as good as before putting then heavier grips.
    Thanks this article helps alot.

  6. Allen Says:

    To follow the line of thought, that a heavier club takes more force to move, And take it to the next step by taking in account the power of the machine moving the putter. In my oversized v8 hemi truck I often pull a light 1940 trailer, I can put a half ton without noticing the weight is back there. Yes it takes more power to move the extra weight but the truck has so much surplus Horsepower the trailer is inconsequential.
    Now, Putters are pretty light objects in comparison to what us humans can carry, i can move one around with great ease. Even though i can feel the higher weight in the putter head i don’t really notice the additional power it takes to move the extra 30 GRAMS! So the physics may support the heavier head on faster greens, but the laws of physics may be irrelevant in this case. Or at least take a second place to the psychology of the equation. If the putter head FEELS heavier then i should up the effort slightly. That would lead to the opposite conclusion, use the lighter head on faster greens.

    • JK Says:

      this is certainly fine. notice how the post goes to great lengths to ensure that no one is misled–this is how physics says it should be and the common understanding. But physics doesn’t take into account the effect of human psychology. if lighter on faster works better for you, then go with it.

  7. Daniel Says:

    Ok so I am imagining the tip of the putter handle being tied to a string and the other end of the string to a hook in the ceiling where the putter is swinging like a pendulum as to be able to hit a ball without arms. If 2 different putter weights are pulled back the same height, the heavier head will have more kinetic energy due to gravitational potential energy(GPE=mgh) and will make ball go further. The force needed to pull the heavier putter back is greater but there is no need to use force after take back because gravity takes over in this scenario. Now, I don’t know how comparable a putt is to the string scenario, but I think gravity and momentum have something to do with this. My question is, how much does gravity actually affect the energy of a putter head?

  8. Gay Alford Says:

    Adding a 15g weight to the toe of my Dianna Yes putter to a 10g in the heel it now feels more balanced as it did feel like the heel was leading, is this because the shaft goes in closer to the heel than the centre of the putter head ?

  9. I like my putter better since the weight fell out. Is it still legal to use it?

  10. foreputter Says:

    helpful explanation. thanks!

  11. Charles J. Stokes Says:

    Your article has validated why when I put on the heavier weights on my putter, it felt more controlled. I actually did find that the heavier putter head gave me a better sense of control both for the roll and distance but I did not know why. You have given me the insight to that “feeling”. Thank you for the scientific explanation. I have always viewed Golf scientifically although I found as an Engineer the complexity of the scientific method is vast. Again….Thank you.
    C.J. Stokes

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