Adventures in putter-building: Frankenstein III

If you have been following my posts here for long enough you will have read (I hope…) several columns on the subject of putting, from why putting is hard, to how counterweighting your putter can help you make more putts, and how a graphite putter shaft can help (but not for the reasons generally touted by the folks who sell them.)

Like most golfers with something of an equipment addiction I own several putters, and consistent with my education and experience as a mechanical design engineer, I like to tinker with them. The five putters which I actually play (I have two or three more which are essentially antiques, of value only as curiosities) have all been bent more upright (within USGA limits, of course), tweaked as to loft (I prefer minimal to slightly negative loft – here’s why) and counterweighted for better balance and therefore better speed control.

The most recent addition to my stable is a self-built putter based on a Ben Hogan Golf BHB-01 plumber’s neck blade putter head. I installed the shaft that came with my Odyssey Golf Tank Cruiser 1 putter—which was re-shafted, for a while, with an early version of the BGT Stability Shaft (about which more here)—and my preferred Odyssey White Hot pistol-style grip. I drilled out the threaded fitting in the butt end of the Odyssey shaft to allow me more options for counterweighting than just the 15- and 30-gram counterweights that came in the Odyssey’s weight kit, and opened up a hole in the end of the Odyssey grip to allow the fitting of one of the range of Super Stroke Counter Core counterweights (25-gram, 50-gram, or 75-gram). I also filed an alignment mark on the top line and filled it with white paint.

The Odyssey Tank Cruiser, meanwhile, had the BGT Stability Shaft replaced with a $15 standard steel shaft. To reduce toe hang I removed the weight from the toe port in the sole, replacing it with cork, and installed a 20-gram weight in the heel port. I installed an Odyssey White Hot pistol-style grip, and opened up the hole in the butt end to take a Super Stroke counterweight. 

While the Ben Hogan-based putter is a “bitsa” build—put together from “bits of this and bits of that”—the real Frankenstein’s monster in my putter stable is the continuously evolving build that started out as a $17 new-old-stock Tight Lies blade putter that I purchased online. This putter, in one of its several modified iterations, was the one that I had in my bag in May 2019 when I played Pebble Beach during the USGA’s media day for the U.S. Open. It was a day that had its ups and downs, but one in which I had a great round on the greens, with eleven two-putt greens, and four one-putts.

Aside from a bit of tweaking for lie and loft, the first big change for this putter was the installation of the stock Odyssey shaft (with the 30-gram counterweight) when my Odyssey Tank Cruiser was getting fitted with the BGT Stability Shaft. From there I went to a more radical change, cutting down and transplanting a graphite shaft into the Tight Lies head—the shaft, an Aldila 350, came from a donor club: the driver that was part of my first set of garage-sale used clubs. As I explain in my column about the benefits of a graphite putter shaft, removing mass from the middle of the length of the club increases stability and improves speed control; “Frankenstein”, as I have dubbed the Tight Lies putter, was my first test bed for the benefits of this concept.

This putter went through several subsequent iterations that involved increasing amounts of lead tape on the head, with corresponding increases in counterweighting, all intended to bring it up to the same overall mass and swing weight as the modified Odyssey Tank. Damage to the shaft that occurred during a bout of loft/lie adjustment spelled the end of that particular experiment, so I decided to take it a step further.

Enter the latest iteration of the Tight Lies putter, dubbed Frankenstein III. It now incorporates a brand new graphite shaft, this time a Mitsubishi Rayon KURO KAGE Black Parallel iron shaft, stiff flex, .370 tip, cut down to yield my preferred 35-inch total length. To make the installation of a butt-end counterweight cleaner I sacrificed a Super Stroke grip for the threaded fitting which takes the Counter Core family of weights. Previous grip modifications to accommodate a grip weight involved drilling a hole in the butt end of the grip to a size that allowed the threads on the counterweight to bite into the rubber of the grip; gluing in the plastic threaded fitting from a Super Stroke grip makes the installation a bit tidier.

Frankenstein III, in all its glory

Shiny-new stiff-flex graphite shaft

Logo partly covered by the grip
shows that the shaft has been cut down

To complete the build I installed a 75-gram Super Stroke Counter Core weight. With a head weight of 391.8 grams, a shaft weight of 56.2 grams (less than half the weight, and at $29.95 less than 1/6 the cost, of the BGT Stability shaft), a grip weight of 67.2 grams, and an actual 74.0 grams of counterweight (plus a smidge for grip tape and adhesive) yields an all-up weight of 592.2 grams, or about 1 lb 5 oz. Thanks to the lack of the added lead tape that had previously been wrapped around the shaft of the 75-gram counterweight, this is about 20 grams shy of the weight of the previous iteration, and that of the modified Odyssey Tank. Loft remains at -1º, and the lie angle is 1º shy of the USGA limit, at 79º.

The 75-gram counterweight installed
in my preferred Odyssey putter grip

The swing weight of “Frankenstein III” is E5, making it a touch more head-heavy than its previous iteration at E4, and considerably more so than the modified Odyssey Tank, at D4, and the Hogan BHB-01 build, at D0. The new build feels well-balanced, and I have found it to be consistent and controllable when practicing on my office carpet (which stimps at about 13–14); I can’t wait for our current bout of rainy weather to end so that I can go try it out on real greens.

Playing around with putters is considerably easier and less critical than building or rebuilding full-swing clubs; because of the lower forces experienced by a putter during use you don’t have to worry so much about whether you got the crucial head-to-shaft bond exactly right. Even if you don’t go so far as to re-shaft a putter, a little bit of tinkering with counterweights in the grip and lead tape on the head may surprise you with the benefits that are derived from improving the balance of your “flat stick”.

Breakthrough Golf Technology extends their reach to the top of the bag

Breakthrough Golf Technology (BGT), the Richardson, Texas, company that introduced a composite-construction putter shaft, the Stability Shaft, in 2018, has jumped to the other end of the golf bag with their latest product, the Brava line of driver shafts.

Breakthrough Golf Technology (BGT) the makers of the multi-material Stability Shaft for putters, has added the Brava line of driver shafts to their product stable. At least they’re not pink…

The new shaft comes in four levels of stiffness – A, R, S and X (“R” for “Regular”, “S” for “Stiff”, “X” for “eXtra stiff”, I guess; I have no idea what “A” stands for, and it is not defined in the online information for the shaft) – for clubhead speeds of 75 mph, 85 mph, 95 mph, and 105 mph. Standard length is 46 inches, and the shafts weight in at 46 grams, 50 grams, 54 grams, and 58 grams, respectively.

The folks at BGT cite something they call “Speedflite NRG™ technology” (no explanation as to its meaning is offered) for the new driver shafts, which are constructed from “premium Toray™ carbon fiber”, which they claim  “translates to less energy needed when swinging” for “an exceptionally stable driver head for more distance and tighter ball dispersion.”

Their ad copy also claims that the Brava shaft is “Designed for maximum ball speed and smash factor because it delivers more center strikes and a better face angle.” Ball speed and smash factor are functions of club head speed and the properties of the club face and the ball, and are affected by the quality of the strike (hitting  the sweet spot matters…); just how a shaft is going to help the golfer hit the center of the club face is not explained; ditto with the face angle claim.

The new driver shaft is claimed to beat two premium driver shafts by up to 10 yards in distance and up to 60% in dispersion, information backed up by a pair of colorful graphs on their website but unaccompanied by any solid data or information about test protocols, etc. If you have read my June 2018 column on the Stability Shaft you may recall the skepticism I expressed at the claims made by BGT for that product and the data presentation they used to back it up. The same holds true for this new product.

The specifications table for the Brava range of shafts offers up data on “torque” for each shaft, a number that is used by shaft manufacturers to represent the torsional stiffness of their products. The term is a misnomer, because torque is a force input that produces rotation or torsion (circumferential stress), not the reaction to that force. That being said, these numbers do give a sense of the relative torsional stiffness of the four grades of the Brava shaft. The numbers that are advertised for this quality of the Brava line of shafts are – from “A” to “X”, respectively – 5.6˚, 4.4˚, 4.3˚, and 3.5˚, but these values cannot necessarily be used to compare this characteristic of the Brava shafts to driver shafts from other manufacturers because there is no uniform industry-wide test standard for obtaining this so-called “torque” measurement.

By the way – comparing the weight of each of the Brava shafts (see above) to the “torque” you can see that the extra 4 grams tacked on for the “S” shaft isn’t buying you much in the way of increased stiffness, by whatever measure is used.

Let’s get some data

My evaluation of the Brava line of driver shafts doesn’t stop at their marketing BUMF; the nice people at BGT (who may not have actually read my review of the Stability Shaft) set me up with an “S” flex Brava shaft for my Ben Hogan GS53 Max driver. (In a case of spectacularly bad timing, the Ben Hogan Golf Equipment Company had just closed its doors when I went to their website looking to buy a hosel for BGT to fit to a Brava shaft so I could swap it for the UST Mamiya Helium F4 shaft I had ordered my driver with. A timely suggestion from a Twitter acquaintance sent me to the OEM suppliers market, where I was able to purchase the needed item.)

I sent my Hogan driver off to BGT, and just a few days later I got it back, along with an S-flex Brava shaft fitted with the Hogan hosel I sent along with the driver (the “X” flex shaft wasn’t available at that time or I would have probably gone with that – the weight is closer to that of my gamer.) After regripping the Brava shaft with my preferred grip, a midsize Golf Pride Tour Velvet, I gathered some preliminary data about the two setups:

Shaft                               All-up shaft wt*    Full club wt    Swing wt

UST Mamiya Helium F4        139.8 gm             333.1 gm            D5

Brava 54G S95                      117.9 gm             311.1 gm**         D4

* (incl. grip and hosel)

** (22-gram difference is about the weight of $1 worth of quarters)

With these numbers and the two shafts, in hand, I went to my local Golf Galaxy to get some comparative performance data on the two shafts. (Shoutout to Steve Kobota, Operations Manager at my local Golf Galaxy store, for setting up and running this testing session for me.)

Numbers don’t lie – but sometimes they’re hard to understand

The first thing to know when evaluating launch-monitor data from shots taken by a 65-year-old 25-handicap who doesn’t play nearly as much golf as he should is that I am not Iron Byron. I am the first to admit that my swing is inconsistent. The launch angle and spin rate numbers that came out of my Trackman session bear that out, and I would not use them to come to any conclusions about the relative qualities of the Brava shaft and the UST Mamiya Helium shaft that I normally game.

As for smash factor and carry yardage, as I stated above, smash factor is more a function of the driver head, the quality of contact, and the ball being used (the hitting bay was not equipped with my usual Titleist pills) than it is of the shaft, and since carry yardage/total yardage is calculated by the Trackman system (it was an indoor session) and is not actual data, I think that the best indicator of the relative qualities of these two shafts to come out of my hour in the hitting bay is club head speed.

The bottom line – What am I getting for $399.99?

The club head speed numbers that I achieved with the two shafts were remarkably similar. I actually achieved my maximum clubhead speed with the UST Mamiya Helium shaft, the heavier setup of the two by 22 grams, which I swung second, when I was already a bit tired. The average club head speed was slightly higher (for a few more swings) with the Brava shaft, but only by a miniscule 2.2%.

Club-Avg-He	Club-Avg-Br
84.8	86.7
Max	Max
90.7	90.5

The shot dispersion patterns were quite similar between the two (but nothing to write home about, courtesy of my intermittent two-way miss—remember, 25 handicap.)

All in all, despite the small—but noticeable—weight advantage of the Brava shaft, in my hands its performance was essentially identical to the standard-option UST Mamiya Helium shaft I normally play, and such similar performance would make it difficult, in my mind, to justify the purchase of the $399.99 Brava shaft. The smart play, if you are interested, is to try the shaft yourself, but that might not prove to be easy to do as the number of brick-and-mortar stores that carry the line of Brava shafts is limited; they are mostly Club Champion locations, according to the BGT website, so if you have one nearby you are in luck.

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† (You may note that my average club head speed numbers indicate that I should be swinging the “R” shaft, but I have always held that the best option for consistent shots is the lightest/stiffest shaft you can handle. My explanation as to why this is true can be found in this post from September 2019.)

The Stability Shaft – how good for your game is a high-tech, multi-material putter shaft?

As I mentioned in my previous post – Putting is hard – but you already knew that, right? –  I bring years of experience as a mechanical engineer, and a naturally skeptical nature, to the task of reviewing and evaluating golf equipment. I am very critical of the performance claims that equipment manufacturers make for their latest design innovation, and I subject them to close scrutiny. Putters seem to be the worst offenders when it come to gibberish tech-speak, but many golfers still seem to eat it up.

Because of the difficulty of putting and the irrecoverable nature of poor performance on the greens, club manufacturers seem to be constantly introducing some new high-tech innovation that will help golfers improve their putting. Sometimes it’s a training aid, sometimes it’s a design tweak to the putter itself, but it seems as though there is always something new coming down the pike when it comes to putters.

The latest high-tech innovation to come to putters is the Stability Shaft, from Breakthrough Golf Technology, with the involvement of well-known golf club pioneer Barney Adams, the inventor of metal fairway “woods” – the original Tight Lies clubs. While I will admit that this is a fairly new approach – little has been done with putter shafts over the years – the needle of my skepticism meter started twitching as soon as I read the ad copy on their website.

Wait, it does what?

The four-part, multi-material Stability Shaft is made up of a carbon-fiber composite tube, which forms the grip end and most of the length of the shaft; an aluminum insert placed inside the carbon-fiber tube at its lower end to “reinforce flexural rigidity”; and a 7075 aluminum alloy connector which adapts the upper end of the shaft to the conventional stainless steel tube which mates with the putter head.

The main structure of the shaft is described as “Eight layers of high-modulus carbon fiber specifically layered, wrapped and widened, with a no-taper design to greatly reduce torque.” This statement makes little or no sense in terms of mechanical attributes of the structure, or the functional requirements of this portion of the putter shaft. The little loading, either in bending or in torque, that a putter shaft experiences is concentrated at the other end of the shaft, where it is joined to the putter head.

Regarding the aluminum insert, their ad copy says, “Through finite element analysis a light-weight, 22-gram aluminum insert was developed and precisely located to reinforce flexural rigidity.” (“Flexural rigidity” is an oxymoron, by the way.) If the high-tech “high-modulus carbon-fiber” main body of the shaft is so precisely designed to resist deformation due to torque loading (which is what they really mean by “…a no-taper design to greatly reduce torque”), why are they adding half the weight of a golf ball near the middle of the shaft to increase rigidity?

Another claim for the Stability Shaft is that it “…delivers the face squarer at impact for improved accuracy and solid feel…”. The forces acting on a putter are low at impact, even lower during the swing. The rigidity and stability of a putter shaft is concerned with forces that are substantially less than those encountered in a full swing club, so what forces do the designers of this shaft feel are acting to deform the shaft of a putter during the swing? The only rotation experienced by the putter face will be the result of rotation of the entire club, caused by variability in the player’s grip, and arm and hand movement.

Fancy data says what?

The website for Breakthrough Golf Technology offers a pair of graphs which are said to show the velocity of the heel and toe of a putter with a standard steel shaft and with the Stability Shaft. Represented as showing toe and heel velocity at a data rate of 2,500 frames per second, based on the “Frame Number” scale along the bottom of the graph, they depict a little over 1/10th of a second in the motion of the putter, about 3/4ths of which is before impact. The lines for toe and heel are fairly uniform preceding impact (though apparently offset, which must be for clarity, to differentiate between the two, because unless the putter is moving through an arc, they should be moving at the same rate), but after impact the graph for a “Standard Steel Shaft” shows significant deviation of the two lines from each other, represented as a difference in velocity between the heel and toe. The graph for the putter with the Stability Shaft shows much more uniform velocities for the heel and toe, ramping up again evenly after the expected drop at impact.

Putter with a standard steel shaft

Putter with the Stability Shaft

Leaving aside the other questions which these graphs raise (the unlabeled velocity scale, for example, and the lack of information about how the data was gathered), what value is there in uniform velocity between heel and toe, if indeed that is what is actually being depicted, AFTER impact? If the ball is no longer in contact with the club face, no movement that the club face undergoes has any effect on the motion of the ball.

The amount of time represented in the graphs after impact, again, based on the frame number scale along the bottom, is approximately 4/100ths of a second. The changes in velocity depicted on the graph – which are not quantified – occur in a very short timeframe, and there is no information offered as to the magnitude of the displacement which these “velocity changes” represent. If the concern is the squareness of the club face, it is obvious that the relative displacement, therefore the relative positions, of the heel and toe of the club would be of concern.

You keep using that word. I do not think it means what you think it means

The more I looked at and thought about the data that these graphs are supposed to represent, the more I came to be convinced that these graphs must depict vibration in the club head measured at the heel and toe ends, not the velocity of the heel and toe of the club head.

The graph for the steel shaft before impact shows tight, consistent data for the heel and toe, with after-impact data that is consistent with undamped vibration in a rigid material, such as a high-strength stainless steel shaft. The graph for the Stability Shaft depicts slightly less-regular behavior before impact compared to the steel shaft data, and a well-damped behavior afterwards. The latter is consistent with a system which contains a vibration-damping component such as a wound carbon-fiber tube.

How I evaluated the Stability Shaft

My experience with the Stability Shaft is based on the conversion of my Odyssey Tank Cruiser blade putter. Before sending it off to the people at Breakthrough Golf Technology, I swapped out the counterweighted original shaft (because I would not be getting it back) for the plain steel shaft from (ironically…) an old Tight Lies stainless steel blade putter. The Tight Lies received the counter-weighted shaft from the Odyssey.

Needless to say, when I got the Odyssey back with the Stability Shaft installed, it felt much different. Not bad, necessarily, but different. The balance was off, for instance, without the counterweight, and I noticed that the head was a bit wobbly in the take-away as a result. In order to make this as complete a test I could, after a few weeks of using the club as-is I decided to remedy that situation.

A trip to a local golf shop netted me a 50-gram counterweight kit for Super Stroke putter grips. Even though I don’t use that type of grip, I was able to install it securely in the grip end of the re-shafted Odyssey – and it transformed the putter’s performance.

Counter-weighting increases the inertial moment of the putter (its resistance to rotation) along the long axis from grip to club head, stabilizing the club during the takeaway and the down swing (such as it is with a putter.) I had noticed the difference with the Odyssey when I first got it, installing the grip counterweight after having used the club for over a year with no weight in the grip, and I noticed it in the Odyssey Mk II (as I am referring to it) with the Stability Shaft. I now own two counter-weighted putters – the Odyssey Tank Cruiser with the Stability Shaft, and the old Tight Lies which inherited the Odyssey’s original shaft – and frankly, it has become a toss-up which one I put into the bag when I play.

In conclusion

Unlike the folks at BGT, I don’t have high-speed video, or sophisticated data-gathering equipment of any kind, at my disposal with which to evaluate clubs – only my eyes, ears, and hands. What they told me over a few weeks of using my re-shafted Odyssey putter is that the Stability Shaft is not a miracle solution to anyone’s putting woes, whatever they may be.

My knowledge and engineering experience told me that the claims that are made in their advertising copy are suspect, and the time I spent with the re-shafted putter showed that, at best, after becoming accustomed to the altered swing weight of the putter, I was no worse off than I had been before. Further modifying the club with the grip end counter-weight improved the swing stability of the “Odyssey Mk II” – which reinforces what I had previously learned about counter-weighting, but did not substantiate any of BGT’s claims.

So – if you have the spare cash to drop $200 on a putter shaft, and really want to explore the option, you may find that the Stability Shaft feels right in your hands, and with your swing; but if a putter with the Stability Shaft works better for you, it’s more about balance and feel that works with your particular stroke than it is about any of the performance claims that Barney Adams and the people at Breakthrough Golf Technology are making.