Closing box

     I closed boxes for SSJ and Nylon models. Both bodies showed excellent tap tone as usual. Although, the tap tone does not tell 100% tonal characters, Lutuz spruce showed pretty much the same tap-tone as German top. So, this is at least a good sign for me. Nylon model has an European top as my standard, and showed pretty long sustain for a tapping.
      I also completed Graphite rods installation on the 12-strings guitar I made last year. I replace the finger board, and partially re-finished the neck. After 2-weeks of curing the finish, I completed the final polishing. Now, I am working on the fretting work for this 12-strings guitar.

Ready for closing box

Both SSJ and Nylon models are ready for closing box. Both models employ the lattice bracing for the back. This time, I made a super light weight back lattice bracing design. This design is for more lively sound tuning to make better vibrations. SSJ model has massive graphite braces for preventing the body deformation. Nylon model does not need the graphite bracing; however, this model has a massive L-shaped head block with strong but light weight solid linings for the top side. L-shape head block has an extended fingerboard support all the way down to the 24-th fret. This fingerboard support makes crispy sound for very high fret position. After close the box, I will do many detailed jobs for purfling and binding installations.

Side and Back are ready for assembly

I completed 12-strings guitar modification projects. Now, I back to the guitar making. I installed Graphite braces for improving the body rigidity. These graphite braces will be able to prevent a slow neck angle change issue over many years. I also shaved back lattice brace cross sections to minimize weight. Now, the side and back are ready for assembly. Next week, I will close the body.

12-strings model design modification

I changed the body construction for 12-strings model. This is for minimizing a body deformation issue. I have been observing substantially serious action change issues for the 12-strings model. This is due to the strong string tensions. To minimize the body deformation issue, I installed two massive graphite rods from a top of the head block to the bottom of the body wast. This design is not my original idea. Similer techniques have been seen many hand made guitar makers such as Mike doolin guitars and McKnight guitars. I followed those ideas. I hope this design modification improves the action change issue.

Back bracing

Lattice bracing for the backs were installed. African black wood back has three piece jointed structure; therefore, I insulated two joint patches. Myrtle back has a conventional two piece back. Both backs have the 5x5 lattice bracing design. Vacuum clumping is an essential tool to make a void free gluing, because the lattice brace requires even pressure for all bracing at the same time. Traditional clumping technique is not able to install lattice brace properly. Conventional ladder bracing has been using for past two hundred years. Now, we have the vacuum clumping technique that enables to use more advanced bracing technique.

SSJ and Nylon top making

Both Nylon model and SSJ model completed top making. As you can see the first picture. This wood dusts are from one brace shaping. I have been using hand planes to shape cross section of the brace. It is a time consuming process; however, I am able to control to obtain a desired cross-section quite precisely. Brace shaping for Nylon and steel models are completely difference. Nylon model requires very tiny and delicate bracing. My lattice size is 3mm (Width) x 7mm (High). For the steel model, X-brace size is 8mm (Width) x 12.5mm (High). Although the Nylon model has 3mm width, I still shape the cross section as the V-shaped manner. This complicated brace shaping process makes pretty good sound response. This is a beauty of hand guitar building. This time, I also used the Adirondack spruce for bracing materials. I am quite excited about testing the sound response. Next week, I start making the back bracing. I will use the lattice bracing design for both Nylon and SSJ models.

Lattice Bracing Install

   I installed lattice bracing for the Nylon model. Lattice bracing is made by European red spruce same as the top material. I have been using the vacuum clamping system for the gluing process for the lattice. Vacuum clumping is able to apply stronger and uniform pressure for the clumping. Also, the water based glue cures much faster in the vacuum environment. 20-minits is enough to apply clumping force for the lattice install. After install the lattice, I shaved the lattice brace as a triangle cross section to minimize weight. This is a time consuming process; however, removing excess bracing materials improves sound quality dramatically.
    I also made a sound hole, and installed a Rosetta. Rosetta has a simple black-white-black border design. Outside trim for the Rosetta is Ebony. Internal borders are made by maple and black dyed maple. This nylon model has an unique offset oval sound-hole that works as conventional sound hole and sound side port. Also, this offset sound hole layout generates much stronger buss tone no matter what bracing pattern is used.