00 Falcate braced Cocbolo\Lutz Spruce Steel String Guitar blog:
August 24th 2014
I cut the back braces to length, put a 15' radius on them, glued the mess up in my vacuum box, and tapered the ends. I just have a little bit of work to do on the rims and I can close this guitar.
When I trimmed the back, I sort of liked the cut offs and am considering using them for the head stock veneer. A bit of blond shellac sort of pulls things together color wise. The bindings and the arm bevel are going to be ebony.
My original thought was to use the cutoff from the rosette. I am starting to fear that it might be a bit of over kill color wise but the tuning pegs, strings and my logo with tone things down a bit .
I will give it some thought but I am open to input.
August 24th 2014
I was leaning toward the burl but the guy I am building the guitar for really likes the cocobolo set I am using and wants to use the back cut off. I do plan to flip it so the V runs up and out I think it will look good.
I finally have the guitar ready to close. Moving forward from the last post I needed to install the end wedge, side reinforcements, and two mounts that will allow me to add mass to the sides. If needed I can lower the top resonance with little change to the air and back resonance by adding side mass.
I went back to installing the end wedge before installing the back and top. I was convinced to wait until the box was closed for the last guitar, but I found it to scary to cut the wedge in to the top and back. Cut a little too deep and the cut is viable in the top and or back. To install I cut out the wedge and double stick tape it into position on the tail. I cut pretty deep with a scalpel and then while protecting the sides cut the rest of the way with a razor saw. I chisel all the way to the end block.
To set the wedge in I just tap into place with glue and the purfling. All and all I like the way the African Blackwood looks with the cocbolo and it will match nicely with the ebony bindings I am using.
I reinforced the sides to install a side sound port with a piece of scrap East Indian Rosewood. While it will be hard to see, it will blend with the cocobolo and will let me get away without binding the sound port. I used LMI glue to glue a paper pattern of the sound port into position. I drilled a couple of holes and used a jig saw to cut close to the line I wanted to use in the pattern. I cleaned up the cut with a rasp and sand
paper, slowly working to the line.
With the hard stuff out of the way I glued down some reinforcement strips and the weight mounts that I made and routed the rebates for the back braces. I cleaned up the inside of the rims to 320 grit sandpaper. The sound port makes it easy to look into the guitar so I thought I should clean it a little better than I usually do.
I will sleep on it before I close the box, back first. I have rechecked the top geometry and made sure that the bridge is set for a short scale 14 fret guitar. So far everything looks good.
September 12th 2014
I got a bit more work done on this guitar. I glued on the top and back using CAM clamps. I glued on the back first and made sure that the insides were clean. Before gluing on the top I checked the angle of the upper bout to make sure I had a good angle that will match the desired neck angle. When I checked I found that I was a bit steeper than I wanted. I used a plane and a 40' radius dish to take a bit of the curve out of the top mainly lowing the waist a bit. Ultimately I was happy and glued the top down.
I waited for a couple of weeks to get my self aligning binding cutting head from Luthier Tool. I really like this product as it mounted like a router template. So I was able to easily install it in my Fleishman binding machine. Now I can use a 1/4 down cut spiral bit in stead of use the router bit with bearings.
Routing the channels went well. I am installing BWB purfling on the top so I need a ledge for it. The bearing on the binding head was low enough so I was able to route right into the arm bevel area with out causing harm. This allow a clean transition between the the binding and purfling channels and the cut for the arm bevel. I did shooth out the transitions a bit with sand paper on a small block. I did tape a bit of purfling above the the end wedge on both the top and back to lift the router at that point. I went back with a chisel to cut cleanly to the end wedge purfling.
I used fish glue to glue on the back bindings. I took some time to get the bindings and purflings and the end wedge joints to look good. Fish glue as a long open time, so I taped both bindings in very tight and then wrapped with a rubber strap.
September 21th 2014
I finished the binding, purfling and glued on the arm bevel ebony veneer. Once finished sanded and cleaned up it should look pretty good.
I posted the bevel stuff in a previous guitar but I have made some changes. My technique is based on what I learned in Kent Everett's Transitional Arm bevel DVD. This time instead of backing the purfling on the top bevel with a cutoff from the sound board I used a strip of ebony binding that bent to shape and tapered the edges so that it joined with the ebony binding and purfling line that followed the sides. Using the ebony gave me some wiggle room in getting a good top to bevel transition. I also used fish glue to allow me time to comfortably tape and pin down the bindings.
Once the glue cured I planed the strip of binding and purflings on the top and sides in the bevel area flush and used a combination of planes and cabinet scrapers to shape the bevel. In the picture you can see how once shaped the added binding material fills in the gaps left between the basswood substrate and and the top and the sides.
Once the bevel was shaped to my liking; it is important to have a good angle between the purflings and the bevel so that the veneer can be sharply cut flush. I put some heat tack veneer glue on both an over sized piece of ebony veneer and the bevel. After the glue dried to the touch, I ironed the veneer onto the bevel. After a few hours I flooded the seam of the veneer with thin CA and trimmed the veneer close with a razor blade and used a card scraper to cut the veneer flush.