Making Violin Ribs
Now that I have completed the process of modeling the Guaneri 'del Gesu' Vieuxtemps violin and making the mold its time to start building. I will be leveraging the CNC as much as possible in order to make theses parts as precisely as I can. In the past I have bent sides for guitars, mandolins, and violins by hand on a bending Iron, while this process is defiantly challenging and interesting I have also found its accuracy a bit lacking. At some point I started making bending jigs with the CNC and bending the ribs of instruments over these forms. The process of bending sides over a form with a heating blanket is fast and accurate.
There are 4 four previous Instructables covering this build if your interested in this project.
Making the Side Bending Jig
Because the profile of the instrument was made by proportional design and with the fewest arcs necessary to form the shape, designing the bending jig was simple. I created the first form for the lower and upper bout and created a tangent arc to join them. I subtracted the rib thickens dimension for this form so the bent sides would fit very precisely into the interior rib mold. the C bout form was designed in the same way. Then I cut them out on the cnc.
Cutting the Corner Blocks
At around 6:00 min in to this video I start cnc cutting the corner blocks and gluing them into the mold. I left a small amount of stock to leave on theses parts so I could fit them very accurately to the internal mold.