BMT - No Longer Just For Drivers....

For the past few years I have been using a driver shaft fitting system called BMT - Butt Mid Tip - to choose the best driver shafts for players. It was developed by Jerry Hoefling, Master AGCP Clubfitter.

The basics of this system are to measure a player's swing speed, overall swing tempo (time from start to finish of swing) and release point - where he/she releases his/her wrist cock. From these data, the system develops an estimated butt-mid-tip flex appropriate for the measured parameters. Then - using a data base of hundreds of shafts where measurements of shaft butt, mid, and tip stiffness have been made - it is possible to identify a shaft or shafts that are good fits for the way players swing their drivers.

The premise of using this fitting system is that it leads to using a shaft that best fits the player's swing characteristics, and so will significantly reduce the dispersion of driver results. Some prominent fitters have had 100% success rates using this system.

Over the past year I have been learning more of how other fitters have been applying this system to also fit fairway wood shafts. The way most have done this is to measure 3 wood swing speed, tempo, and release and use the same shaft BMT data - adding 10 grams of shaft weight to the shaft weight used for the driver - to find a good shaft for a player's 3 wood.

There are a lot of companies now that are developing fairway wood shafts that are meant to be put into 3 woods without any tipping. ACCRA shafts are a great example of this approach, and a number of PGA tour players are using ACCRA shafts with great results. The value of doing this is to promote a higher launch for 3 woods - or simply for your longest fairway wood.

I tested this on my fairway woods recently. A good BMT shaft fit for my fairway woods is an SK Fiber TT 80 A flex shaft. So I put this shaft into my Wishon 949 MC 3 wood without any tipping, and built my 5, 7, and 9 fairway woods with the same shaft but with enough tipping so the butt flex of all of the clubs would be the same. So far I have been very pleased with the performance results of these reshafted woods, and believe this is a great approach for fairway wood shaft fitting.

Tony

Tiger's Driver Shaft.......BMT Driver Shaft Fitting?

I did not watch a lot of the tournament this weekend, but did hear on Thursday or Friday that Tiger was playing a new shaft in his driver, and then on Sunday (and today also) that he is going back to the shaft he was using previously.


I highly suspect that Tiger has intimate knowledge of the shaft flex profile in his driver shaft.....at least I hope so. I know from my relationships with AGCP clubfitters that shaft flex profile is a key variable in finding the right shaft for a player. Jerry Hoefling Sr., one of the AGCP Master clubfitters, developed an excellent system for fitting driver shafts based on their shaft flex profile in the butt, mid, and tip end of shafts - called the BMT fitting system.


This system is based on the theory - proven to work pretty well by experience of a number of clubfitters - that a player's swing speed, swing tempo, and release point - where he releases his wrist cock in the downswing - can be used to determine an appropriate shaft for that player. We have a database of measured shaft flex profiles based on 7 flex measurements along the length of a shaft. Jerry developed a system to correlate this profile to butt, mid, and tip shaft stiffnesses - and then relating these stiffnesses to a player's swing characteristics. Particularly for late releasers - players who hold their wrist cock until JUST before the ball - shaft tip stiffness is a key to identifying a shaft that will produce a minimum dispersion of drives for a player.


Measurement of the three key parameters is not too difficult - a launch monitor or swing speed meter can be used to measure swing speed, tempo timer to measure swing tempo, and review of video of a swing to determine where the player releases the club. The most difficult measurement to determine well, in my view, is the release point.....and with the right camera this is not too difficult to get either.


So Tiger.....all the best at the Players Championship this week. I suspect that going back to his normal shaft will produce better driving results for him.......but I have to admit I would LOVE to know the exact specs on the driver shaft he is using!! And I also know that there is no way these specs will be common knowledge.......


REMINDER........I will be at Centenial Golf Course on Wednesday from 3 to 7 pm - along with Bridgestone Golf and some OEM companies - and if you are I will provide you with some Launch Monitor measurements of your driving characteristics. And if there is time, I will interpret some of this data in terms of what could help you improve your driving distance. Perhaps I will see you then (assuming no rain!!).


Tony