I received a small package with a guitar. Small because the neck was loose and the guitar body unusually small. Not so surprising since it is a Russian seven-string guitar from 1873 with an adjustable Stauffer neck that is not glued to the body. I have a hard time turning down interesting projects like this. Got these pictures of it, and it didn't look too difficult.
I had no idea how bad the condition really was. The bottom was already loose, so inspecting it internally was no problem. All the bottom braces were missing, the ones in the top were still there. It had been refurbished in the past and converted to 6 strings, and not in a good way. It is almost impossible to describe how bad the condition was on the sides, here are some pictures of the misery.
It took a while to understand what had happened. The original sides were probably made of very thin mahogany, about 1 mm. It had, of course, cracked and one or more repairmen had patched up the inside with various patches and cleats. I even think that some patch was in birch fists! Then they had leveled the outside and sanded down the original sides, still thinner, and stained both the inside and the outside.
When I carefully peeled off all the glued patches, most of which were stuck with dry and crumbly old hot hide glue, the sides were thinner in places than a 0.6 mm thick veneer! One of the sides was also completely broken off in one place. Some holes in the sides had glued in repairs that came off with the patch on the inside when it was detached.
The neck block was also in bad shape. It had cracked and been patched up. Part of the old Stauffer mechanism, in the form of a rectangular piece of metal, had been repositioned at a 45-degree angle across the crack, leaving a hole in the neck block where it was originally fitted.
The missing bottom braces had pushed out the sides and left holes at the top of the sides along the edge. The top had also received repairs and a thick piece of maple glued in as a bridge plate.
The neck, on the other hand, was in OK condition. There was life in the old brass bar frets. The last free part of the fingerboard had bent up a bit, and the neck itself was also bent. The hole for the seventh tuning screw in the head was plugged. When I received the guitar it had no tuning screws (and no saddle), they were to be replaced with 7 new Wittner screws. The fretboard itself had a crazy radius as it often does on these, would guess around 3-4″, a Telecaster has 7,25″ and the curvature is greater the smaller the number. The worst bend I can work with in my fret press is 6″, so it's not exactly easy to work with.
The bottom was also in good shape, just a small crack in the center joint at the top in addition to the missing braces.
The black painted maple bridge was original, but converted to 6 pin holes with a shim glued on top.
Someone who had previously renovated the guitar had stained both the bottom and the sides inside in a dark red-brown color. At first I thought it was original and tried to mimic the color on the inside of the new patches I glued in, but realized after a while that it was added later as the label had some of that color around the edges. In some of the pictures you can see the staining I did with the help of potassium permanganate, but it was easily washed off later with oxalic acid and some sandpaper.
The first thing that had to be fixed was the extremely thin sides. The only solution, apart from completely new sides, is to glue on new and better patches on the inside. For that, I used a 0.6 mm thick maple veneer. Strips of veneer with the grain across the grain in the sides were glued in six rounds. First a wide patch between the two thin kerfings, then two narrower strips to tie the kerfing to the rest of the sides. There were cracks along the edge of the kerfing that could not be glued together otherwise.
I have already made cauls for the inside lined with pieces of rubber yoga mat that allow you to get pressure on the entire surface of the glued veneer. The cauls mad of board had sawn out notches to be more flexible. On the outside I use equally flexible birch with standing grain, intended for manufacturing sweeping baskets, as a counterweight. It works very well on a curved surface, and you get a tight gluing of the veneer with hot hide glue. Plastic wrapping is used on both sides to avoid gluing cauls to veneer or the sides.
A piece of kerfing was also missing against the top.
The many string holes in the top were replaced with a sawed-out hole in the middle and a piece of spruce which partially filled the hole in the top and which also acted as a bridge plate. At the same time, one of the top braces was replaced as the original was bent the wrong way and also cracked when it was removed for re-gluing (it had a run-out). It is a departure from the original, which completely lacked a bridge plate, but the top needed to be strengthened in any case. One of the sides was also attached to the end block with a few layers of veneer, as the side was cracked right at the edge of the end block.
A replica of the bridge was made and glued in place. My OCD couldn't handle the original being misplaced, so it was glued straight and not in the exact same place as the original. Later, a saddle ditch was milled for a saddle instead of the brass fret.
When it came time to glue the bottom back on, there was very little to glue the bottom to. I glued on an extra kerfing in the form of sticks in soft and light linden wood. I made a temporary tool with adhesive sandpaper to smooth the original kerfing for gluing the new one. I also added some extra thin reinforcements in spruce in the top as well, in the open area in front of the bridge plate and on both sides of the sound hole. An old cracked top needs a little help to hold, especially for seven strings.
Before the bottom could be glued, I needed to work with the neck block and the Stauffer mechanism. A new mechanism had been purchased as half of the original was missing. To reinforce the neck block, I glued a 4 mm thick maple plate into the bottom of the neck pocket with my jig. The hole left by the old mechanism was filled in with spruce, and 4 mm was milled out and replaced with the maple plate. With the help of the plexiglass sheet and the screws, the jig can be adjusted so that the milling takes place in the same plane as the bottom of the neck pocket. The maple plate is sawn and fitted with the help of a little tape for the right measurements.
The neck was heated straighter in a few passes, first the overhang and then the neck itself was bent back.
One of the frets was lower than it should be, but with bar frets it's fairly easy to pull the fret up with a pair of pliers. Practically! The bottom frets were lower, probably ground down due to the "uphill" in the fretboard overhang. A few bindings at the neck attachment needed to be glued back using long clamps and a soft metal sheet.
All cracks in the top received cleats. The bridge plate was given small rounds of maple as reinforcement around the peg holes, and the bottom was cleaned from the ugly red-brown stain. The bottom was shrunk, and instead of trying to force it into place, the best solution was to mill for a binding around it once the bottom was glued. I used birch in the binding, which was then stained to the same color as the bottom and side. Some pictures from the bottom gluing.
The seven new Wittner screws with built-in mechanics were easily mounted with a drill and broach and did not need to be glued, I think they are very good. The guitar was strung with its special strings and tuning and measured for intonation. It is incredibly nice to have an adjustable neck, otherwise gluing the neck is the most difficult part to get right. In order to move the saddle forward on the replica bridge in the finest rosewood, I glued in an approx. 2 mm thick piece of bone at the top of the neck pocket. I imagine having a hard material in contact with the neck is good. The saddle and nut were made of camel bone, only the saddle was intoned. A Gator 3/4 case fit well.
Got a short feedback when it arrived: “I got the guitar today. Great! What a great job you have done!” 🙂
Wow, what an incredible job. Bravo!
Thanks! You know how bad the condition was. Now it's back to get the straps in the right place as well (everything after the 12th strap was wrong, at most about 3 mm), but it's fine with that.