Ric, I couldn't conjure up anything from the archives on the Spurlock tool, but then I'm fairly inept at computer things... I think Fred addressed capo dressing a few years back in his very thorough manner. As I remember here is the gist of it; the v bar can't be too sharp because it will wear/fracture too fast and soon be rounded anyway, but now with string grooves. He also referred to a .5mm contact point and that stuck with me. However, Ted hit the nail on the head by using the word "curvature". Now if there is curvature there must be a radius, arc, diameter, etc. or at least someway to quantify the curve. Ted's method of referring to a drill bit size/radius works for me. Maybe your V looks sharp but is actually the same as I see as a radius at the very point. (Maybe all roads lead to Rome.) Or, maybe if you see my redressed capo you'd say it's a V. It looks like a V, but it actually isn't sharp. In fact, just the rounding of my flesh as I sand it rounds it over to a small radius. The fret file just seems to make everything more uniform and is very fast. Regards, Jim Busby -----Original Message----- From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of RicB Sent: Tuesday, April 24, 2007 3:29 AM To: caut at ptg.org Subject: [CAUT] Hardness of termination vs string breakage (was Re: restrung D) Hi Jim Please do see if you can spor it up. It wouldnt be the first time different ways of describing something seem in dissagreement more then they end up being :) But to try and specify better the profile I've always used. It is a definite V form, not an U. Flat contact area to the string with the edges of the profile cutting away from this surface area as opposed to rounded of. Ted said something about the rounded profile compensating for the string length change in the initial phase of the strings vibration... the quote was "A vibrating string is quite evidently being stretched at amplitude . and the consequent lengthening is offset by the alternating termination point caused by the deflection of the wire around the radius of the bar" This is simply false, no disrespect intended. If a rounded termination could effect any change in speaking length it would do so only in vibrational directions close to vertical, and this would result in differences between those directions in other directions... and this is the whole single string beat thing again. There IS a difference in resultant inharmonicity caused by the two different profiles. The sharp/thin profile allows the string to flex more around the termination, and the round/wide causes more of a bend. In the former inharmonicity is lowered slightly. Whether that is or isnt a desirable is another matter entirely. Again.. read McMorrows stuff on this, and there is a lot of discussion surrounding this in the archives. I'm off and running ! Cheers RicB Hi Ric, I'll check. Maybe we're talking different things here. I think 2.5mm is the radius. Your .5mm profile might mean the same thing.(?) .5 radius would mean 1mm diameter. Am I thinking correctly? Have fun! Jim
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