String length: 640mm
Body length: 460mm
Upper bout: 275mm
Lower bout: 335mm
The maple back is in excellent condition and is finished in a vibrant deep brown-red that is most likely a shellac based spirit varnish. The finish has worn away from the edges of the contour and most notably from the bass side upper bout in a manner that suggests long use by a single individual. The neck and peg head are ebonized maple. Note the wear mark from the player's thumb.
The top and back are both strongly arched measuring 7 mm at the lower bout. This degree of arch is maintained at the waist and upper bout. The back also slopes from the tail to the neck joint making the tail block deeper than the front block. Strongly arched backs are not unusual but such an arch on the top is a unique feature. The construction of the arch is also unusual. The soundboard is not domed like Spanish guitars, but bent side to side from the center line along the entire length of the top. The neck which sits flush with the fingerboard continues along the same plane.
The side ribs are contoured, top and bottom , to accommodate this arching.
The rib height including the top and back thickness :
Neck joint 65mm
Upper bout 63mm
Lower bout 69mm
Unfortunately these features do not show up readily in the photos.
Here is a close up of the top showing the major cracks. Others are too small to show up in this photo, but all needed attention. This work was the focus of my restoration.
Several cracks ran under the bridge and you can see an example under the right arm of the bridge. I thought it was necessary to remove the bridge in order to do a proper repair. There was already a slight lifting of the bridge at one point so it was easy to slip a knife in the opening. I dabbed alcohol on the knife blade and allowed it to wick into the opening. Alcohol crystallizes old hide glue, weakens the bond and allows the joint to be separated safely.
Older cracks had been filled with shims and several were secured with interior wood cleats. Since there were many cracks to repair it was necessary to remove the back of the guitar. I found an opening between the back / rib joint and wicked alcohol into the joint like I did for removing the bridge.
After one hundred and eighty-four years the back retained its arch free of its bars. I knew it would be some time before I re-assembled the guitar so I made a arched pine form to hold the back. You can see it in the background. The side ribs of any style of guitar have the tendency to change shape whenever the top or back is removed so I made a collar to hold the guitar while it was dis-assembled.
There were several areas where the lining was loose or broken and another location where a bar end had punctured the side rib.
The guitar does not have maple binding around the back. The finish has uniformly worn off the edge of the guitar exposing the light colored maple.
I took care of these problems immediately. A simple fix with a spring clamp and a piece of cork was sufficient in some cases but a two part contoured caul and c-clamps were necessary for others.
It is interesting to note evidence that this guitar was built quickly: the notches in the linings for the harmonic bars ends are too large and the lining for the top is cracked at the waist but not broken through.
This photo shows the external collar that I made to help retain the contour of the guitar once its back was removed. The harmonic barring is a simple pattern as is the shape of the interior blocks. There is a repair inscription between wood cleats in the lower bout.
The harmonic bars are spruce with the grain standing up. They measure 9mm thick and 15mm high and are arched as I previously described.
Rather than trying to make a tiny shim to fill a narrow crack I enlarge its width to about .75mm and make the edges parallel. Most cracks occur in the light colored soft wood of the annual rings and are usually fairly straight. The thin dark lines are denser and denote the late summer growth. These harder grain lines serve as a convenient boundary. Not only are they a visual aid but their hardness acts as a 'fence' to guide my knife. Usually I work free hand. There were several wider cracks or cracks that crossed an annual grain line. Because of their width I treat these differently. I use a metal ruler to scribe a pair of parallel lines that are wide enough to encompass the crack. I then gouge out a channel with a veining tool to a depth that is about 2/3 the thickness of the top. This method provides a 'floor' for the shim to rest on and a third gluing surface that provides extra strength for the joint.
I choose the wood for my shims from an old stock of very close grain soundboard scraps and try to match the color of the original soundboard. I can cut very accurate and clean edged shims with my miniature table saw. I bevel one edge of the shim slightly so that it slips more easily into its channel. It needs a good fit but not a tight one. The shim will swell when the glue is applied and it may not fit in the channel. A certain amount of fitting is usually required. I widen the channel a little or narrow the shim a little. When I'm satisfied with the fit I work quickly, brushing a thinned mixture of hot hide glue into the channel and pressing the shim home. I wipe away the excess glue with a hot damp rag, followed by a dry rag and then cover the repair with painter's masking tape to slow the glue's drying which allows the wood to swell a little resulting in a very snug fit. Everything takes time.
There is still a lot to do, but that's enough for now.
All photos by the author