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Hi guys, I just joined this group and really need an answer to a question. I have searched all over and can't find any info. Here goes... I am assembling my first complete build. It's my own body design with a Fleta inspired sound board. I used Courtnalls solera plan to do my work on. He says to ramp the neck section down 3mm from the 12 th fret position. But he never says to add any angle to the sound board platform of the heel. So when I glue the neck to the soundboard will it not have a gap once a clamp down the neck? Or if I glue the platform to the soundboard first, will it not bend/warp the sound board when I clamp down the neck? Am I putting too much into this? I have done lots of cosmetic repairs and set up adjustments. This is new ground for me. Can anyone help me out?

You have identified an issue to deal with. Some taper the back of the fret board under the body to match the angle mismatch, others build with the fret board elevated from the body a bit, cantilevered. I build with the neck flat to the sound board (no angle or ramp) and taper the complete fret board to give me the angle I want to get the right height at the saddle.

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http://www.Harvestmoonguitars.com

Thanks for the insight. If I go with the flat neck (no angle) couldn't I scoop my dish out to about 5 mm and still accomplish a good angle to start with? Then get the fine tuning from the bridge and the fret board?

That might do it. Draw it out in cross section with the height of the dome, saddle height, required action etc. It's an unusual way of doing it though and 5 mm would be considered a lot dome.
I give an angle to the Neck and taper the underside of the board from the 12 th fret onwards.

Very few books explain this well, but it is critical. The other posters have pointed you in the right direction. One of the things to consider, though, is the shape of the top around the sound hole. Doing big scoops in a solera can make the top come out looking concave (hollow) around the sound hole, which is not a look I like, but it does provide a geometric solution. Avoiding the hollow look and getting all the angles right is a pretty subtle trick. Draw it out as Michael suggests, because, if nothing else, you'll get a real appreciation of the issues.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Yeah I did a mock up today and didn't like he outcome. The 5mm scoop is just oo much for a traditional appeal. So here is my solution...Ramp the solera 2.5 mm, carve the soundboard platform of the heel to transition into the angle and the rest I should be able to fine tune with the bridge and board. Would love to hear what the Sr. Builders here have to say. Thanks for helping me guys! I have found that luthiers are a dying breed to an almost lost art form! I'm all traditional ( no power tools except I use a band saw to mill my lumber.

There is a formula for adjusting the various parameters for a neck geometry of a classical guitar.
Try plugging the values and see what you need to do to set up the solera



Action =
0.5 x [(String height + doming) - (Fingerboard thickness + Fret crown height) - Neck angle]
+ Neck angle

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Sen CL Goh
http://senguitar.blogspot.com