Another guitar from the waiting room was used for a OldGuitar this summer. A slightly later European parlor from the 1920s. At that time, people began to manufacture more or less imaginative and decorated parlor guitars. Some with a different and odd body shape, this one just had a different bridge and some extra mother of pearl bling around the sound hole.
It was in perfectly OK condition apart from cracks in the top and damage to the top d under the bridge. It is possible that the bridge was not original given the quite a few string pin holes in the top, but I could not see a "shadow" in the paintwork of a previous bridge. I wrote about how I repaired the top under the bridge here a previous post.
When I start a new batch, I initially work in parallel with everyone on repairing cracks, installing carbon fiber rods in the neck and making and gluing new braces. When it's done, and it looks like the pictures below, I finish the guitars one by one.
I took some pictures while I was making and gluing braces, among other things, for this guitar. I have a small stock of fine blanks for braces, partly those I got from my friend Björn and which are made of 60 years old Swedish spruce, and partly blanks bought in from Germany of good quality. The Swedish spruce is the best and I use them in the top, the bottom has to make do with the ones I've bought from Germany.
It all starts with the selection and cutting of suitable spruce blanks for all guitars. They are then shaped to a standard format that fits my triangulation jig with my drum sander, 15 x 8 mm. The next step is to give the braces a radius, the bottom braces a 20' radius and the top braces a 30' radius. The brace blanks are planed and roughly sanded, with my pad with a coarse self-adhesive adhesive sandpaper, to roughly the right shape before I use an LMI jig to sand in a nice bend with a bottom face that is perpendicular to the sides of the brace blank. Nowadays, I also use a scraper to smooth the rough sanded surface under the brace to be glued.
All bottom braces and all but one of the top braces are triangulated in a special jig in a ladder bracing. In an X-braced guitar, you cannot use the jig for the large X-braces, they must be shaped by hand. With the jig, it is quick to get a perfect triangulation of standard blanks with the help of a sharp plane.
The bottom braces are simple and one-dimensional and can be glued using my old method with a caul with the same radius as the underside of the braces. To extend the open time of the hot hide glue, I take the opportunity to use a heat lamp. An advantage is that you can glue several bottoms, as the finished clamp package can be moved away for the next gluing (as long as the number of clamps are enough). The top braces, on the other hand, are always glued in my go-bar to a radius disk to get the right bend on, among other things, the bridge plate in two dimension both along and across the top.
A replica of the original bridge, which was in black painted maple, was produced in rosewood. It was made a little wider and longer to fit the saddle and cover most of the wound in the top under the brold bridged. For some reason, the original bridge was wider below the string pins with too little room for a saddle in front, so I turned it upside down. This meant that more of the wound from the original bridge was visible when the new bridge was glued.
The flat maple board was replaced with a 16″ radius rosewood board. New tuners were fitted.
A working moment that I have started with recently is to adjust the neck angle reasonably correctly before gluing the fingerboard and bottom. When I have the neck angle "right", I can then decide if I need to change the radius of the brace under the fretboard before gluing it to avoid having to make a triangular shim under the fretboard on the top. To get a fair emulation of the neck angle, I use the bottom as a template and make sure the edge of the sides matches the length of the bottom perfectly at the neck and bottom block using an adjustable threaded rod through the endpin hole. With a matching bottom to the sides, the neck block has the angle it then gets when the bottom is glued in place.
With the correct geometry on the neck block, I can fit the neck angle with a loose fingerboard so that a straightedge laid on top of two 0,5 mm blade gauges hits the top of the bridge. The frets are 1 mm high, but I want a bit more height on the saddle to compensate for any bending of the neck, hence the 0,5 mm. It almost always works... The brace under the fingerboard is clamped at the ends when testing so that the top is pushed up by the radius bend of the brace.
The "wings" on the neck foot are sanded and adjusted with a sharp chisel to the correct neck angle. When adjusted, shims must be glued into the neck pocket to make the attachment tight. I have made maple shims in various thicknesses, 0,3 to 0,6 mm, with my drum sander. One or more shims are glued in with superglue (to speed up the process) and the neck is used as a caul with some household plastic wrap as a release agent. Finally, I will find both the right angle and have a tight attachment of the neck.
Now the brace under the fingerboard can be given the correct radius to avoid a triangular shim under the fingerboard on the top and is glued in place.
With all the ribs glued, a final sanding of the inside and fitting of a K&K mic is done before bottom gluing. Assembling a K&K with an open bottom takes no more than 10 minutes.
With the bottom glued, first the fingerboard and then the neck is glued. A final adjustment of the neck angle is usually needed if you're not lucky, but most of the rough work is already done.
The frets were assembled and crowned. The guitar was measured for intonation and an intoned saddle was made. I took some pictures of how I mill the ditch for the saddle using the measurements from the intonation. The intonation points are marked on a piece of tape, and where the saddle bone ditch is to be milled is marked. With a razor blade, I cut out the position of the saddle ditch in the tape. The contrast makes it easy to see where to mill.
I give the saddle a slight back angle by shimming up my Stewmac jig on one end. Two angle hooks, one on the top and the other on the jig, allow me to set the right angle. I also check that the jig is level across with a ruler so that the saddle ditch don't get an uneven bottom. I have a bunch of thin aluminum plates that I can pad up the sides of the jig if it's not flat.
A segmented saddle was fabricated, adjusted and intoned. The guitar received a coat of new spirit varnish and was vibrated in for three days before it was completely finished. The last steps are always to mount the side dots, the label inside and a guitar strap button on the neck.