Fred, I think we're close to saying the same things, maybe not. On a sample note; if these *four* adjustments (presuming you meant to include rep. lever height) do NOT result in synchronization, AND correct jack alignment to the knuckle... yes, we would diagnose the other three tolerances and make a global correction before continuing with jack position. Once our sample note(s) met all criteria though, we would regulate jack-position entirely by synchronization via any method that uses the jack position-crew rather than the drop screw. (personal preference) Then, we quickly examine jack-alignment note-by-note to *confirm* that the jack is aligned to the knuckle. If it is not, (and this is rare) even when let-off, drop and lever height have been adjusted *globally* to our sample tolerances, then any jack that is found *synchronized but not aligned* becomes exceedingly valuable for fine-regulation and micro-diagnosis of that individual note. A jack that is out-of-line stands out plain-as-day to indicate even the slightest regulating error. No temptation to fudge here... go back and fix it. (global pre-diagnosis/individual micro-post-diagnosis :>) I think fine-regulating is somewhat like setting a temperament; a good tuner can start with any note, but in the end all individual tolerances (intervals) must be exact, in order that the last note satisfies all tests. So, to be clear, we rarely ever *regulate* jack-position to the knuckle core visually, though we're perfectly capable, and I in particular have enough drop-screw indents in my forehead to prove it. ;>) We *regulate* synchronization, to a very precise tolerance (no early-up or early-out jacks allowed!), then *confirm* visually that all the jacks are in the right place. In the end, the equation is solved when all parameters are met. Best regards, Mark C. Brandon University -----Original Message----- From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of Fred Sturm Sent: August 24, 2009 12:18 PM To: caut at ptg.org Subject: Re: [CAUT] CAF On Aug 24, 2009, at 10:29 AM, Mark Cramer wrote: > IME, once escapement is synchronized via the jack, if the jack is > out of > line, it indicates an error with one of my other a/t adjustments... > i.e. > drop a bit wide, lever a bit low, etc. and I will need to go back > and find > it. So, jack position can be a very precise after-touch diagnostic > as well.. > that is if we don't fudge it by merely lining it up to the core. ;>) With respect to Eric S's "final adjustment," I think he is on the right track in the sense of looking for a very fine and crisp feel of the jack and drop being simultaneous. But I don't think that adjusting the jack position (relative to the knuckle) is the right way to get there. I prefer to diagnose and decide what is wrong. Could be only one of three things: letoff, drop, or jack position. So figure out which one, and correct that. And I have a somewhat different method of checking. Eric does it by pressing the key down. I prefer to take the key out of the picture. I get a more sensitive feel by simply using a finger to lift the wippen, positioned under the lever a little forward of the jack. Raise until you hit the resistance of the rep spring. Ideally, when you push through against that resistance, the jack just immediately begins to move. If it is wrong, the jack movement will either be delayed a bit, in which case the jack will have risen above the level of the of the rep lever before moving; or the jack will move first, in which case you will have felt a little bump before the big bump (jack tender contacting the button before the rep hits the drop screw). It kind of goes along with lightly tripping each jack to check for alignment of the rep top with the top of the jack. A similarly very sensitive touch is needed, and it can go pretty fast if you have done good work. If not, it will tell you real fast that you haven't, and maybe you'll decide to go through and advance or retard all the drop adjustments a tad, as an example, then re-check. Regards, Fred Sturm University of New Mexico fssturm at unm.edu
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