Scotty Cameron has said that cutting his putters down or changing the weight scheme will "ruin" his putters. By this, I think he means that he has crafted into the putter certain performance characteristics with the relationships between putterhead shape and mass, hosel placement or location, and shaft vibrational properties. Karsten Solheim used to do much the same, designing into his putters a very specific "feel" from the relation of the putterhead to the shaft.
From the point of view of physics, cutting 1.5 inches off the putter produces several GENERAL changes to varying degrees: 1. overall weight of the putter; 2. swingweight of the club; 3. vibrational properties of the shaft after impact with a ball. The shortening MIGHT also alter the tempo IF it results in a different distance from the pivot in your body (usually the clavicle) to the ground, but this might well stay the same if you grip a little higher or extend your arms a little more, etc.
Specifically, cutting 1.5 inches off a 35 inch putter will make the swingweight a little lighter, with a little less "feel" for the swing of the putterhead. How much less feel? Not a lot. What difference does it make? It depends upon your stroke style and the existing level of sensitivity you rely upon for that stroke. Some putter designers, Scotty Cameron included, want the golfer to rely upon a slight sense of lag in the putterhead in the down stroke. That is, the golfer sense that the hands are being moved (by the shoulders) slightly faster than the putterhead, so the golfer "feels" a subtle lag in the stroke. This is a very, very subtle effect that does not, strictly speaking, depend upon swingweight. Nonetheless, if you are tuned to sense this and rely upon sensing it for a consistent stroke tempo, then making the swingweight a little lighter might adversely affect your habitual feel. This is not to say you can't get around that by learning a new and perhaps different or slighter sense of lag even with the lighter swingweight -- you can. You can also putt very well without the "lag" feel at all.
The second effect that would bother Scotty is changing the vibrational feel of the putter in the hands AFTER impact. A shorter putter would have a quicker vibration (higher frequency) -- sort of like the difference between putting with the tip of a baseball bat versus putting with the tip of a cue stick (to exaggerate to highlight the effect). Does it matter, really? Probably not.
What can you do to preserve or restore putter performance characteristics AFTER cutting the putter down 1.5 inches? If you know the swingweight ahead of time, you can add lead tape to the putterhead to get the swingweight back close to what it was earlier. This is likely to take too much lead, so you can only add a modest amount. The lead will alter the moment of inertia of the putterhead, which will change the off-center twist properties and also change the "send" and possibly the location of the sweetspot. The "lead on the head" will restore somewhat the formner overall weight of the club.
You really can't do much to restore the post-impact vibrational frequency of the shaft without switching out the shaft with one having more flex than the original. But you chances of getting a shaft with precisely the right extra flex is extremely remote.
You might consider adding weight to the handle end of the shorter putter, using either a heavier grip material or a weight plug / insert like the Balance Certified Golf (
http://www.balance-certified.com) system. This would restore the overall weight of the club, keep the "send" and momentum / inertial properties of the putterhead the same, and would move the vibrational "node" or cancellation point higher up the handle and closer to the center of your grip. Weight at the butt end of the club reduces swingwieght (each 6 grams removes one swingweight point), but I suspect this would also alter the vibrational frequency of the shaft. I'm not sure how the shaft frequency might change, though. My intuition tells me the extra weight concentrated at the butt end would make the frequency lower, like the slow bounciness of a tightrope walker's balance pole, but who knows?
Then there is the issue of effecgting the resale value of your putter. I imagine that, things being the way they are, if you placed a cut-down Scotty Cameron putter on eBay, it would not fetch as much as it would if it had not been cut down. But, if you win 19 Majors with it first, I'm sure the value would be high enough to forget about the fact it was cut down.
All said and done, I would explore the possibility of ORDERING a 33.5 inch putter directly from Scotty, combined with selling your existing putter unchanged. If that is not a good plan for you, then I would suggest borrowing a shorter putter (33.5 inches) and hopefully borrowing a 33.5 inch Scotty Cameron putter before cutting your putter down -- to assess what you think of a stiffer putter and how it affects your personal "feel." You might also try to get a response to this question from someone who has actually cut down a Scotty Cameron as you propose (I haven't) or try asking Scotty Cameron directly what he says.
In any event, let me know what you decide and how it works out.
Cheers!
Geoff Mangum
Putting Theorist and Instructor
The PuttingZone.com
http://puttingzone.com
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