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Hi everyone,

I am going to bend my first set of sides tomorrow. I figure it would be good to cut the profile of the body depth before bending. When builders list body depth of a guitar at 4 5/8", do they generally mean the entire body depth (including thickness of the top and back plate) or the height of the tail block and neck block (internal depth of the body of the guitar). Thanks!

Peter

P.S. I successfully joined up two tops today - victory 1 of build 1.

Peter,

As I understand it, the "single" body depth you referenced is the depth at the tail block. The depth at the neck is usually
significantly smaller, so the body is tapered. Some people theorize that this taper helps keep the guitar from having a
single, very high Q, air resonance.

As far as cutting it ahead of time, I think it would be dangerous to try and cut the sides to exact dimensions. Since both
top and bottom are curved, the sides are not a straight taper. Some of us cut the back profile into the bottom edge of
each side before bending, because the bottom has the most curvature. I always try and leave 1/8"- 1/4" extra along the
top edge, to allow for any small mis-alignments in gluing the sides up in the mold. It's not difficult to take that much off
with a small hand plane, and then finish off with a sanding dish.

_________________
Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

Thanks, Gene. That was very helpful info.

If the body depth at the tail block is listed as 4 5/8" for instance, does that mean that the tail block is about 4 3/8" tall (4 5/8" minus a 1/8" top plate and 1/8" back plate)?

Thanks,
Peter

Yes, that is correct Peter. Just subtract the top and back thickness to get your side depth (width, depending on how you look at it). I don't think many people use a 1/8" back plate thickness though. I tend to go for 0.090-0.100"

Measurements of guitars are generally given as finished measurements.

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Thanks for the reply, Rod. Got it!

One advantage in bending sides unprofiled is that if you have an edge crack or ripple you can often just plane it off. I was taught to bend sides at their full height, clamp them in the mold, scribe the lines from a template and then plane them down. ( My teacher actually used a coping saw- but this tends to split along the grain lines, at least in IRW). Good luck with your build!

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Thanks, Jon!