Howdy all, I'm reworking my nut (no wisecracks, please). Five hours of filing the main shape, and fine filing the grooves with those nice "Swedish pattern" files, mainly the end of the rat tail. I was aiming to get down to about 1/32 (.8mm) over the first fret, knowing I'd need more yet to get the action right. I got a bit aggressive with the chanterelle and brought it to 1/64 (.4mm) over that first fret. But the action is perfect, and it happens that the nylgut string I'm using there is .40mm (and for general info, Aquila recommended nylon for the longer, 63.3cm, instrument, but sent me a tryout on nylgut - it has held for four days now - I think it may work).
I seem to remember that a luthier on this list said that the height above the first fret should be about the same as the diameter of the string. So my question for the list is "do I file my 'nut grooves' to a uniform height above the first fret, or do I make each different using the diameter of the string as a criterion (and allowing that the octave strings in the lower register may want a different groove than their paired wound companions)". I yet have work to do on the 'bridge saddle', that anathema to the purist, but that is easy. My bridge is higher than it need be to prevent 'buzzing', but isn't so high as to make the action difficult at the higher frets. The current intent is to get the lower frets right for quick action and clean sound. My gut reaction is that the "over the first fret" height should relate to the diameter of the strings involved rather than be some fixed height. It is a slow process, but it is a work of love. To work the grooves one needn't unstring, just relax the strings involved and push them to the side and take out that fine thin rat tail file. Then try it, then do it again. The pain in the butt is that the strings relax and take some time to bring to pitch again - so any suggestions as to planning the process are welcome. BTW, while I'm at the questioning, I find that the Nylgut octave strings in the lower registers take a bit longer to "stretch out" and maintain pitch than the treble Nylguts - is that common experience, or do I have slippage in my pegs that I haven't noticed? I would be logical that the thicker Nylgut there might take longer to decide its pitch, but I ask your experience. Best, Jon
