Chapter 3
Parabolic dish to do
Page 4
Parabolic dish to do-Now that the solera is leveled, the dish that creates the doming of the guitar must be created. In the image is a small cast iron plane that has been modified to make a hollowing plane simply grind a curve on the long axis and width a belt grinder or grindstone will do the job. Grind the blade to fit the planes sole take care not to burn the blade go slow cool quickly in water.This plane is usefull for shapeing braces .The depth at the center of the dish will be 3/16" and the center of the dish will be at the center of the bridge saddle. At the inter section of the bridge saddle, to be determined by the fret scale) and the centerline of the guitar body drive a 4 penny nail 1/2 or more inches deep marking the location for the next steps. Take the small curved plane you have just modified and plane carefully towards the center mark from all directions takeing fine cuts leaving the outline of the guitar line showing. Do not go to the full depth with the plane the next tool in the image will do this. This tool will be rotated to finish the dish. To make this tool take a piece of wood 1-1/2" by 1-1/2"square and as long as the one in the image.Mark the center and drill a hole the diameter of an 8 penny nail,turn the tool so that the hole you have just drilled is parallel to the top of your workbench,measure in 2" from each end and drive a nail three sixteenths from the edge then at the middle drive another nail at the edge or corner on an angle, bend this nail up as are the first two that you drove. Now you have three points established take a flexible metal straight edge and placeing it on the outside of the center nail and on the inside of the two outer nails and you will have the curve ,mark with pencil and plane to shape. Put some limit blocks on the outer edges to control depth plane the limit blocks if needed to go deeper. The brace nearest the soundhole on the bridge side of the solera will limit the circumference of the dish. To make the dish wrap the tool with 60 weight sand paper slitting the edges to allow the sandpaper to bend unifornly,put an 8 penny nail in the hole in the radius tool and drive the nail in the hole in the solera made by the 4 penny nail,and rotate the tool to make the dish going to finer sand paper to finish.Now blend the dish to the contours of the guitar with scraper and sandpaper.The brace above should be 1/8" dished at the middle going to zero at the neck top join. Make smooth gracefull curves. Sand lightly and draw the layout of all braces on the solera,cut out the area of the sound hole and on the oppisite side of the sound hole area make the solera thinner to allow small clamps to be used to clamp the top through the soundhole of the solera. Shellac or french polish the solera and apply coats of paste wax to protect and stop glue from adhering.
