David, I don't know about any books or articles, but... The procedure I recommend is as follows. The idea is to measure the exact speaking length. That is the length of wire that actually vibrates in response to a hammer blow. From a design standpoint, this is from the centerline of the front termination on the plate to the centerline of the back termination on the bridge. Through the agraffe section this can be taken from the center of the agraffe to the center of the speaking side bridge pin. I recommend using a Stanley tape measure that is marked off in decimal inches and mm (the part number escapes me right now, if you need to know I can get it for you). For rescaling work it is accurate enough to hook the end of the tape over the agraffe and read to the front edge of the bridge pin. If the agraffes are abnormally wide you can compensate by subtracting an appropriate amount from your reading. Through the Capo-d-astro bar/V-bar section it can be a bit trickier. Starting at C-88, I use a thin 150 mm steel rule (made by Mitutoyo -- again, I can get you the part number if you need it) that I have beveled slightly on one end. I slide this beveled end along the strings to the V-bar, getting as close to the actual string/V-bar intersection as possible. I then read the length at the center of the bridge pin. When the speaking length gets to be longer than 150 mm, I switch to an 18"/450 mm rule. This one is a bit wider than my 150 mm rule, but at this point it is quite usable. Again, work the end of the rule as far in to the juncture of the string and V-bar as possible and read to the center of the bridge pin. Wire diameters are measured with a micrometer. On wrapped strings you'll need to measure both the diameter of the string core and the overall diameter of the wrapped section. Often old strings have a healthy buildup of rust and general corrosion. Check under the dampers on the steel strings, they're often somewhat cleaner there. You may have to clean off a short section to get a reliable reading. To save time, think ahead. Remember that, unless there is at least one individually tied string in the unison, unisons will be paired. That is, the same wire size will have been used for two consecutive unisons. It is only necessary to measure one string of each pair. That should do it. Remember that this is not rocket science. Accuracy and consistency are important, but there is some tolerance allowed. For string lengths I suggest reading to the nearest mm through the agraffe section and to the nearest half-mm through the V-bar section. As to whether to use decimal inches or metric, the choice is yours. My scaling program is set up for string lengths in mm and wire diameters in decimal inches. String lengths in decimal inches are also acceptable. Fractions should have gone out with square grands. Neither I nor my computer works with them. If you have other specific questions on the process, please don't hesitate... Regards, Del ------------------------------------------------------------- Vanderhoofven wrote: > Very sorry to be asking a beginnerish type question, but what is the proper > place to measure speaking length? Can you suggest the title of a book or > an article that would have good information on where to measure? > > Thanks! > > David Vanderhoofven > MSSC > Cottey College
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