Bracing for a Nylon string

[Robert Freemond]

Hope this isn't over done question, but I'm thinking about building a Nylon string Archtop like Thorell's Gianina.

I would like some help finding bracing ideas.

[Alan Carruth]

The best ones I've made have been like the 'normal' steel string archtops, except that:
1) I use the lowest density wood I can find,
2) the arch is kept low: 15mm overall from the bottom of the plate to the top of the arch,
3) the top is thin; about 3mm, and
4) the X bracing is very light; 6mm wide and only tall enough to get the 'free' plate modes to work right.

The good ones so far have been made on a 16" Small Jumbo platform. All of this stuff is interrelated.

Alan Carruth / Luthier

[Robert Freemond]

Thanks Alan, This will be very helpful. When you say ( I use the lowest density wood I can find,) does this mean that you hand pick Spruce for density ? or do you cedar etc.

[Alan Carruth]

So far I've used spruce, chosen for low density. If you can't hand pick, Engelmann tends to be the lowest on the average, although it varies, of course. I have a cedar top that's earmarked for an arch classical at some point.