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Well, today I started my very first nylon string guitar ( Macassar ebony with maybe Sinkerwood). My own design with a 14 fret neck... we'll see!

Anyway, for you guys that build classicals.... do you leave to rims completly flat or profile it a bit?

I was told to leave it flat and put a slight radius on the top braces... I don't know. Can somebody shed a light light??

Thanks!peterm39055.0591898148

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Hey there Peter,

I followed Campiano's book for my first classical and put a slight curve in the main brace under the upper bout.

For my next classical I'll be using a solera....a workboard with a hollow sanded out in same extending from bridge area to soundhole. See Courtnall's book for details on making a solera. Not sure on the exact radius of the resulting top but maximum height of the sound board doming is about 2mm above soundboard rim...I guess its in the vicinity of 25-28' radius.

With the rim you have a choice of leaving the area flat or carrying doming of soundboard right to rim. If you have the top curved right to rim then youll have to shape the tantallones or lining when you glue the sides in. If you leave the top flat about 25mm in from the rim then it makes gluing top to side a bit easier. Again this is explained in Courtnall's book.

Good luck with the classical and look forward to progress pics of same.

Cheers kiwigeo39055.2300115741

Most descriptions and plans I have seen suggest that the tone bars have flat bottoms, and all the doming is in the lower bout. The doming in the Courtnall solera is all below the soundhole, starting near the lower tone bar. Top rim is flat. On the three Rodriguez-style bodies I've built, all the main top braces are flat. (These were all built on the Courtnall solera).

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Jim Kirby
kirby@udel.edu

I build my classicals with a transverse bridge bar located directly under the saddle line (a la Bouchet and Freiderich). In a departure from Cumpiano, Courtnal, and many others, I contour my top braces -- the bridge bar and the fan braces -- to a 25' radius, using a radius dish and sandpaper. My theory behind this is to have a top with as little "internal" tension as possible. The upper tone bar, at least, should be flat, or else there might be gap problems between the fingerboard and the soundboard.

Be sure to radius the underside of your bridge (and the gluing caul). This adds significantly to the maintenance of the top arch on classicals.

A comment about a 14-fret classical: this will locate the bridge about an inch or so forward, away from its optimal location in the center of the lower bout. I don't know how much this will affect the sound, but it will have some effect. I guess if I were doing this, I'd give some additional consideration to the bracing pattern I employed.

Best,

MichaelMichael McBroom39055.5299537037

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Live to Play, Play to Live

You've gotten some great advise so far!
I radius my lower boutbraces and the transverse brace below the s.h. to 30'
I use a 30' dish and the fans so to speak glue in with just go-bar pressure but the transverse is shaped on a router table with a template.

As Mike said leave the upper transverse brace flat or very slightly arched so there will be no problems gluing on the f.b.

I have done 25' archs also and actually like that better so will use that from now on!
Good luck -take your time and listen to the woods!

Mike Collins
www.collinsguitars.comMike Collins39055.6774537037

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Mike Collins

[QUOTE=Michael McBroom] A comment about a 14-fret classical: this will locate the bridge about an inch or so forward, away from its optimal location in the center of the lower bout. I don't know how much this will affect the sound, but it will have some effect. I guess if I were doing this, I'd give some additional consideration to the bracing pattern I employed.

Best,

Michael[/QUOTE]

Thanks Michael, I intent to make sure I "re-think" the bracing patterns to take that in consideration. I will move the soundhole forward in order to conpensate for bridge placement.

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Mike an Jim,
thanks for the input...all very helpfull information!

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Peter,

Heres a pic of the solera I made up for my next classical.

Cheers Martin