estebanana -> RE: Body depth contouring (Mar. 30 2013 2:25:51)
|
When the brace ends hit bottom in the mortice you'll see the edges of the back and the top of the ribs and you'll know where to plane to make them fit. Unless your back has a huge high arch, a Spanish guitar back should be more or less in the ball park Just make sure you take some measurements at stations on both sides of the back and make sure they are the same elevation. Jeff mentioned the braces as places to use as fixed points to measure elevation, but you can pick three of four or more places and put a ruler to them and see that each side of the back is the same elevation in all those stations. I think for some it is a thing that you try to nail right away and for others it is more a look a fit thing. Eventually both go pretty fast. I was thinking about this today and I use the same back arch on all the flamencos and I know lofting the waist a bit higher puts me in the zone with my arching. I just have worked it out to be that way. When I cut the mortices and drop the back in I can see where I need to give it a few plane passes here or there at the lower bouts and upper bouts. Then after several minutes of working it that way it just drops in and goes "whooosh" and fits like a vacuum. Well almost. You could get the radius dish too, it just means the guitar will have a more pronounced side profile to the fit. The spherical back really shows a more pronounced fit in regards to the rise and fall of the lofting of the ribs up into the back. I think some people might even brace the back normally without the bracing it into sphere an use a shallow radius dish to get the ribs lofted. it seems like it would work. I enjoy the back fitting process and I like the way the plane of the back looks. The difference between that and the spherical back it the surety that the back will be a section of a sphere and it makes it easy to make the concave fixture which matches like a nested box. The nesting of the spheres, the concave sanding dish fitted to concave bracing dish, removes a certain amount of time and risk from the process, but it's not that much time. They seem about equal in that respect. I think psychologically what happens is that some guys don't want to make the back the same spherical radius as everyone else. If your radius is say 22' just throwing that number out there, you're going to find a guy who says: "Damn that, I'm not using the same damn spherical dimension as everyone else. I make my own arching and it has nothing to do with spheres!" All the fuss is because one guy feels individuality is being pulled out of the equation, literally. I'm one of those guys, but at least I know why we act cranky about this issue. [:D]
|
|
|
|