“It’s got great balance and it’s really forgiving. Actually I really putted well with that putter.”
– Jack Nicklaus
The quote above is from one of the greatest golfers of all time, in reference to the putter he used to win the 86’ Masters. He didn’t know it at the time, because the term hadn’t been coined yet, but he was talking about Moment of Inertia, or MOI. What does that mean? Well, in the simplest terms possible, MOI is the clubface’s resistance to twisting though impact. The higher the MOI, the less the face will twist upon striking the ball. This is clearly extremely important in putting because the fact is the ball is compressing less than a full swing and therefore staying on the face fractionally longer. So why don’t we talk more about it? The simple fact is this: all standard putters manufactured are essentially the same in this category. Think about a Ping Anser or a Scotty Newport 2. What is the difference? They both have basically the same dimensions (length and width) and weight, so therefore the same MOI.
Let’s take a look at a newer model of Jack’s putter from 86’ in this picture. In case you couldn’t tell, it’s the one on the left! There is a DRAMATIC difference in size and a small but noticeable difference in depth than its more traditional counterpart to its right. This putter started what is now a new and improved putter design that everyone should consider.
I talked above about putters needing to change something in order to improve performance. What is it that needs to change? As you can tell from the picture above, it is the geometry itself that needs changing, and here is the science to back it up:
MOI = (Distance from Center of Gravity)2 x Mass
A little “mathy” for your taste? If so, worry not! I am going to put it in more practical terms. Let’s go back to the traditional putter. The face of nearly every single one is 4” across. As we look at this picture, imagine the red square is the face of a traditional putter. You can see that 1. The total length of the face is 4”, and 2. That the distance from the center of gravity (or the heel to the middle of the face) is 2”. So now that we have that understanding, we use our formula. MOI in this case will equal (2)2 x Mass. If we know that the mass of nearly every putter of this design is within a certain range (say 300-350 grams) then logically EVERY putter has almost the same MOI. We are always multiplying 4 x 300-350, in each case.
Now that we understand our limitations with our current geometry, let’s CHANGE it. Take a look at this example:
The putter on the bottom is our new putter. You can see by changing the length of the face we have moved that distance from the center of gravity to 3”. Now our formula is (3)2 x Mass. So we are multiplying Mass by 9 now, not 4. As you can see this will have a tremendous effect on our putters MOI, or resistance to twist.
So changing the geometry of the face length is clearly something that is necessary for putting technology to take a leap forward. What about the top of the putter/distribution of the mass? In recent years the advent of the mallet putter has been a popular thing among amateurs, largely because in increasing the mass the putters MOI also increases. But are mallets the best way to do this? Take a look:
Let’s picture that red square is the top of a mallet putter. The black dot on the bottom line, or the face, is the center of gravity. By increasing the overall mass we ARE increasing the MOI. But in adding mass to the back of the putter we are also shifting the center of gravity backwards, thereby decreasing the MOI again (and affecting other things like launch conditions, etc.). How could this design be improved?
Here is an excellent design improvement. Unlike our mallet putter, the putter on the bottom has weights on both the heel and the toe. This allows an increase in the mass of the putter while keeping the center of gravity in the same place.
So, in going forward and deciding on a putter to use, why not go with one with a higher MOI? That means a bigger face, more weight, and weight distributed to the outside of the club. Hopefully this article has helped to lean you in the right direction. Now get out there and make some putts!
Drill of the Week:
Ending my article the way I did, the “drill” this week is a mental one. Get online, do some research. This is the putter I use:
There are obviously lots of putters out there, and looking into a more balanced putter that keeps the face square longer through impact can only help your speed and line consistency, and therefore results. Happy reading!