> I by myself use >an old wound string to polish the string groove. Apply as much as power >you can give. You will realize a moment the string will slide very easy. >The process is done then. You should use different diameters of wound >strings corresponding to size of the groove. Finally you should control >the edge to the fretbord. This may not be sharp but a little bit round, >otherwise the string could be caught by this or may even be damaged.
Disclaimer: I am not a luther. I think the above is sound advice for wound strings. Simply use a non playing portion of the string or an old string of the same gage. I believe it was Ray Nurse who said you could use toothpaste as a mild abrasive. The real problem, as I see it, is changing gages of strings. When I received my John Rollins alto lute last fall, it had absolutely the smoothest tuners I've ever tried on a lute, despite being more than 20 years old. Perhaps one of the secrets was that the grooves in the nut were not so deep. As soon as I changed strings though, the typical catching and slipping appeared. I believe the grooves must be set up FOR the gages. When going to a larger gage, I think sawing away in the groove, with the same gage you want to use would get it to the right size, but then what happens when you want to go to a smaller gage? I wonder what the consequences would be. I've been reluctant to file away at the nut because I haven't settled on the optimum stringing yet. Lute makers, comments? cheers, -- Ed Durbrow Saitama, Japan http://www9.plala.or.jp/edurbrow/