What is Waggle Factor

By Frank ThomasFebruary 25, 2010, 7:10 pm

Hi Frank,

You recently talked about wearing a glove and how it can affect the swing weight of a club, and I imagine wearing a watch might do the same? But my real questions are: What is swing weight? How does it affect the quality of the swing or the results? And how do I know/figure out what is the proper swing weight for me?

Thank you very much

– Brian


To your first question; What is swing weight?

A great amateur golfer, Francis Ouimet, won various events which included the U.S. Open in 1913. He selected his clubs based on feel – an undefined term but most of us seem to have a general idea what it means. If you waggle the clubs in your set, they should all feel the same, i.e. have the same waggle factor.

Because Francis Ouimet was such a good golfer, his clubs – matched by feel-- were used to develop a balance system. This was done by hanging a weight (approximately 16 ounces) on the grip end of each club and finding a common balance point (fulcrum) from the butt end for each club. This balance point was 14 inches from the butt. Thus, the swing weight system was born in about 1920 and still used today. The swing weight is not described as the amount of weight needed to balance a club but by an alpha-numeric table such as D2 or C9 etc.

Swing weight is a questionable system for several reasons. First, it implies a dynamic measurement which it is not. Second, it can be abused by back weighting or adding weight down the shaft purely to get the same or desired number. Third, it is not very well understood.

Having said this, it must be noted that pure swing weight – variations in shaft length and head weight only – is a good first step in matching clubs, as this is closely related to the waggle factor a term I coined because it is so descriptive.

This waggle factor should be called matching by moment of inertia (MOI). This is a much better method of matching clubs as it takes into account the weight, length and is a true dynamic measurement. If you hold a club at the grip end and waggle it, you will experience a specific resistance every time you change direction back and forth. This relates directly to the MOI of the club about the axis you are waggling it i.e. the grip.

Now turn the club around, holding its head and waggle it. You will find the resistance to changing direction is reduced significantly. The MOI has changed and it feels different. Francis Ouimet, unbeknownst to him, was matching his clubs by the MOI method –  the waggle factor.

Most of us know, having mentioned it several  times in Q&As over the last year, that wearing a glove will alter (decrease) the swing weight of the club by about five points, but will not noticeably affect the feel of the club.
The glove will not change the waggle factor (MOI) measurably.

Brian, now that we are over that explanation, let me say that in general terms the higher the swing weight (pure swing weight), the heavier the head and the more resistance you will feel to swinging the club to generating the same head speed.

After about 400 years of trial and error we have found that a swing weight in the range of about D0 to D3 is a good number for most male golfers. Females generally migrate to about C6 to C9. This, in most cases, is because the shaft length is about 1-inch shorter than men but the head weight is about the same.

So Brian a good starting point for you – as for most men -- is about a D0 or D2.

I am sure we will soon be matching clubs by MOI, which uses a relatively simple scale and takes into account all those variables used in swing weight, but is a dynamic measurement and more meaningful.

Waggle your way around this one, Brian.

– Frank


Frank Thomas, inventor of the graphite shaft, is founder of Frankly Golf. Thomas is chief technical advisor to GolfChannel.com. He served as technical director of the USGA for 26 years and directed the development of the GHIN system and introduced the Stimpmeter. To email a question for possible use in an upcoming Let's Be Frank column, please email letsbefrank@franklygolf.com

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Ortiz takes Web.com Tour clubhouse lead in Bahamas

By Golf Channel DigitalJanuary 16, 2018, 2:19 am

Former Web.com Tour Player of the Year Carlos Ortiz shot a bogey-free, 4-under-par 68 Monday to take the clubhouse lead in The Bahamas Great Exuma Classic at Sandals Emerald Bay.

Four other players - Lee McCoy, Brandon Matthews, Sung Jae Im and Mark Anderson - were still on the course and tied with Ortiz at 6-under 210 when third-round play was suspended by darkness at 5:32 p.m. local time. It is scheduled to resume at 7:15 a.m. Tuesday.

Ortiz, a 26-year-old from Guadalajara, Mexico, is in search of his fourth Web.com Tour victory. In 2014, the former University of North Texas standout earned a three-win promotion on his way to being voted Web.com Tour Player of the Year.

McCoy, a 23-year-old from Dunedin, Fla., is looking to become the first player to earn medalist honors at Q-School and then win the opening event of the season.

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Randall's Rant: Can we please have some rivalries?

By Randall MellJanuary 16, 2018, 12:00 am

Memo to the golf gods:

If you haven’t finalized the fates of today’s stars for the new year, could we get you to deliver what the game has lacked for so long?

Can we get a real, honest-to-goodness rivalry?

It’s been more than two decades since the sport has been witness to one.

With world No. 1 Dustin Johnson and former world No. 1 Rory McIlroy at the Abu Dhabi HSBC Championship this week, an early-season showdown would percolate hope that this year might be all about rivalries.

It seems as if the stars are finally aligned to make up for our long drought of rivalries, of the recurring clashes you have so sparingly granted through the game’s history.

We’re blessed in a new era of plenty, with so many young stars blossoming, and with Tiger Woods offering hope he may be poised for a comeback. With Johnson, McIlroy, Jordan Spieth, Jason Day, Justin Thomas, Jon Rahm, Hideki Matsuyama, Brooks Koepka and Rickie Fowler among today’s dynamic cast, the possibility these titans will time their runs together on the back nine of Sundays in majors excites.

We haven’t seen a real rivalry since Greg Norman and Nick Faldo sparred in the late '80s and early '90s.

Woods vs. Phil Mickelson didn’t really count. While Lefty will be remembered for carving out a Hall of Fame career in the Tiger era, with 33 victories, 16 of them with Tiger in the field, five of them major championships, we get that Tiger had no rival, not in the most historic sense.

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Phil never reached No. 1, was never named PGA Tour Player of the Year, never won a money title and never dueled with Woods on Sunday on the back nine of a major with the title on the line.  Still, it doesn’t diminish his standing as the best player not named Tiger Woods over the last 20 years. It’s a feat so noteworthy it makes him one of the game’s all-time greats.

We’ve been waiting for an honest-to-goodness rivalry since Faldo and Norman took turns ruling at world No. 1 and dueling in big events, including the back nine of multiple majors. 

In the '70s, we had Nicklaus-Watson. In the '60s, it was Nicklaus-Palmer. In the '40s and '50s, it was Hogan, Snead and Nelson in a triumvirate mix, and in the '20s and '30s we had Hagen and Sarazen.

While dominance is the magic ingredient that can break a sport out of its niche, a dynamic rivalry is the next best elixir.

Dustin Johnson looks capable of dominating today’s game, but there’s so much proven major championship talent on his heels. It’s hard to imagine him consistently fending off all these challengers, but it’s the fending that would captivate us.

Johnson vs. McIlroy would be a fireworks show. So would Johnson vs. Thomas, or Thomas vs. Day or McIlroy vs. Rahm or Fowler vs. Koepka ... or any of those combinations.

Spieth is a wild card that intrigues.

While he’s not a short hitter, he isn’t the power player these other guys are, but his iron game, short game, putter and moxie combine to make him the most compelling challenger of all. His resolve, resilience and resourcefulness in the final round of his British Open victory at Royal Birkdale make him the most interesting amalgam of skill since Lee Trevino.

Woods vs. any of them? Well, if we get that, we promise never to ask for anything more.

So, if that cosmic calendar up there isn’t filled, how about it? How about a year of rivalries to remember?

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McIlroy: 2018 may be my busiest season ever

By Will GrayJanuary 15, 2018, 6:28 pm

With his return to competition just days away, Rory McIlroy believes that the 2018 season may be the most action packed of his pro career.

The 28-year-old has not teed it up since the Alfred Dunhill Links Championship in early October, a hiatus he will end at this week's Abu Dhabi HSBC Championship. It will be the start of a busy spring for the Ulsterman, who will also play next week in Dubai before a run of six PGA Tour events leading up to the Masters.

Speaking to the U.K.'s Telegraph, McIlroy confirmed that he will also make a return trip to the British Masters in October and plans to remain busy over the next 12 months.

"I might play more times this year than any before. I played 28 times in 2008 and I'm on track to beat that," McIlroy said. "I could get to 30 (events), depending on where I'm placed in the Race to Dubai. But I'll see."

McIlroy's ambitious plan comes in the wake of a frustrating 2017 campaign, when he injured his ribs in his first start and twice missed chunks of time in an effort to recover. He failed to win a worldwide event and finished the year ranked outside the top 10, both of which had not happened since 2008.

But having had more than three months to get his body and swing in shape, McIlroy is optimistic heading into the first of what he hopes will be eight starts in the 12 weeks before he drives down Magnolia Lane.

"I've worked hard on my short game and I'm probably feeling better with the putter than I ever have," McIlroy said. "I've had a lot of time to concentrate on everything and it all feels very good and a long way down the road."

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What's in the Bag: Sony Open winner Kizzire

By Golf Channel DigitalJanuary 15, 2018, 6:05 pm

Patton Kizzire earned his second PGA Tour victory by winning a six-hole playoff at the Sony Open in Hawaii. Take a look inside his bag.

Driver: Titleist 917D3 (10.5 degrees), with Fujikura Atmos Black 6 X shaft

Fairway Wood: Titleist 917F2 (16.5 degrees), with Aldila Tour Blue 95 TX shaft

Hybrid: Titleist 913H (19 degrees), with UST Mamiya AXIV Core 100 Hybrid shaft

Irons: Titleist 718 T-MB (4), 718 CB (5-6), 718 MB (7-9), with True Temper Dynamic Gold X100 shafts

Wedges: Titleist SM7 prototype (47, 52, 56, 60 degrees), with True Temper Dynamic Gold X100 shafts

Putter: Scotty Cameron GoLo Tour prototype

Ball: Titleist Pro V1x