Moment of Inertia Made Easy

The best way to understand and explain moment of inertia (MOI) is to demonstrate it. I have taken a series of photos which explain how to do this. First, keep in mind that MOI is a measurement that determines the resistance of clubhead rotation on off center (off horizontal center of gravity) hits. MOI has very little effect on exact horizontal center of gravity hits.

Demonstrating MOI is easy. Give it a try!

Photo 1 MOI Made Easy

This is a very sophisticated MOI machine made by Inertia Dynamics which is a division of Rockwell International. This is the same unit that Nike and the USGA use plus a number of other major golf club manufacturers. It is interesting to note that The GolfWorks was one of the very first companies to buy and use this machine. We have had it since 1995.

It works by mounting any object on the spindle making sure that the centerline of the spindle projects through the objects center of gravity. In this photo we are measuring moment of inertia through the horizontal center of gravity plane, thus the clubhead is mounted on the horizontal center of gravity.

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Fitting Wedges

A Few Important Tips

It is very important to have any wedge fitted to the golfer. The lie angle is very important and needs to be properly set so that on ¾ to full shots the clubhead comes into impact with the face plane square to the intended target. If the lie angle is not set properly and the toe is up at impact (lie angle too upright) the ball will be pulled to the left of the target. Conversely, if the toe is down at impact (lie angle too flat) the ball will be pushed to the right of the target.

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Moment of Inertia: What Is It?

How Does It Relate to Clubhead Playability?

There is no question that the buzzword today for all golf clubs, metals, irons and putters is moment of inertia (MOI). Problem is most golfers do not understand what it is and probably a number really don’t care. Well, you need to care because an understanding of MOI can really help you play better and also help you to select equipment where increased MOI can be a big help.

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Determining The Playability of Wedges

Wedges can make or break a golfer’s game. Use wedge playability to improve your score.

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Face Grooves on Irons And Wedges

There are two basic types of groove designs, “V” grooves and “U” grooves. Learn which grooves maximize playability.

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A simple tool to help you find your shaft MPF.

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