Another busy, busy week in the shop! The spruce is flying and the arch tops are taking shape!
The blister on my finger is now just a patch of fresh skin and the finger plane that made it has done a considerable amount of new work.
Monday's repair class this week consisted of a long over due look at the frets and fingerboard of my favorite Stratocaster. In last year's repair class I took some time to re level and crown the frets which took care of the few buzzes and several deep dents in the frets, but left me with very low crowns. So low that the neck felt odd to play. So I have chosen to replace them all together with new medium-tall wire and start fresh. This process began with heating and gently pulling out each of the old worn frets, then lightly sanding the fingerboard to smooth and restore the 12 inch radius.
After cleaning up the board a bit but leaving its well worn feel intact, I pressed in 21 new frets and gave them a dab of glue for good measure. I have found that the glue seems to lubricate the fret slots and help to fully seat each fret. When pressing each fret is clamped in place for a minute while the next slot is prepared. This ensures the fret seats and stays seated. Once they are all in the frets are leveled with 400 grit sand paper. after all the frets are level to each other they must be crowned, re-shaped, and polished all of which happen fairly quickly if the first few steps are done well. Next week i will finish off by shaping each end of each fret by hand and polishing them all to a high shine.
CAD class is getting increasingly interesting as we begin applying all of the techniques we have learned to our specific field. This week we Learned how to use an image to help draw a mandolin body from scratch in the program. The finished drawing was a hollow body with arched top and back. full 3D rib structure, and f-holes revealing the hollow inside. In the coming weeks we will learn to draw necks and other parts and begin designing our own instruments.
Arch top construction class saw the beginning of one of the more difficult aspects of the hand carving for the mandolins. The Scroll...... The elegant carving of the upper shoulder scroll on the f-5 mandolin is what sets it apart from its simpler cousin the A-style. Carving this area by hand is all about being able to see what looks good, judge the grain of the wood, and make what you see happen on the surface. The carving is done mostly with finger planes and gouges, then will be cleaned up with scrapers. Each scroll will be different depending on how each carver sees it and chooses to carve it. Even in well known brands of late, until CNC machine carving each scroll and arch was slightly different, making each instrument unique.
Along with all the carving we took some time to prepare our side/rib material for bending by thickness sanding them down to about 1/16 inch thick. To achieve this quickly and uniformly we use a time save thickness sander. the pieces are fed through the machine and each pass sands off a controlled amount equally. The finished product is flexible enough for steam bending and still strong enough for supporting the top and back of the instrument.
Look at all that FLAME!!!!!!!!!
Before beginning to bend the ribs I had to make clamping cauls that fit to the inside mold's curves. This will ensure that once the rib pieces are bent they can be firmly clamped to the corner, neck, and tail blocks for gluing. The cauls are made from scraps of poplar cut to shape and line with cork to protect the wood.
After getting my scroll area caved up nicely, i took my top wood to a dark room and held it at low angles under a raking light. This allows for seeing slight high and low spots on the surfaces and any ridges left from carving. The high areas catch the light and cast a shadow beneath them. Those high areas arethen taken down smooth with scrapers leaving a smooth curved surface. The next step on the outside will be to begin sanding it smooth and final blending all of the curves together, but before that happens the inside surface must be carved out and graduated for thickness.
Light from the bench lamp shines right through the thin re curve area around the edge of the top.
Thanks for checking this out and following along! Tune in next week for rib bending and more!