More about our soundboards and backboards
We approach the carving of our soundboards and backboards as an art. Our boards are carved on custom 3-dimensional pattern carvers that we built in the late 1960s. The pattern masters where created by hand from templates and forms that were taken directly from original F5 and F4 mandolins and an H5 mandola, and have been continuously modified over the past 45 years to perfect every curve, shape, and graduation.
Soundboards and backboards are delicately graduated to within sanding thickness of their final size and shape. Aside from final detailing of the scroll area, no further carving or scraping is required to the outside or inside of our soundboards and backboards.
As shown in these cross-sectional photographs, the graduation of our soundboards and backboards is done with great precision. The upper photograph is of a soundboard cut through the center across the width of the board. The lower photograph is of a backboard cut through the center through the length of the board. Note the thinness of both boards at the recurve.
Every soundboard and backboard is weighed for its density prior to carving, and carver settings are made based on our IMS (Interdependence of Mass and Stiffness) tables. The target measurements for minimum and maximum thicknesses are established before carving, and the resultant actual minimum and maximum thicknessess are taken once the boards are carved.
The average thickness of every soundboard and backboard is measured after carving to ensure that the carving results meet the pre-carving expectations. Each board is stickered with the results.
Our soundboards and backboards are pattern shaped around their perimeter to their final shape (unless you tell us to leave them oversize). We machine a flat plane for the fretboard extender (F5/A5/H5) so that the extender will fit squarely and perfectly in place. The notch into the scroll is shaped as part of the profiling process.
We draw a pencil line to indicate the cut-off point for the 15th fret cross piece on our soundboards so that you can perfectly match them to the headblock cap and cross piece. (These photos of our soundboards show how they come from the carver - no subsequent sanding was done.)
Here a backboard is held behind a soundboard (note the neck nub of the backboard) to show the perfectly matched routing of the outside profiles of both boards. Our headblocks are also cut to this shape so there is no need to cut through the soundboard, headblock, and backboard to create the opening in the scroll.
The apertures on our soundboards (f-holes for the A5 and F5 mandolin and H5 mandola, and an oval hole for the F4 mandolin) are pattern shaped for precision. If you plan to tune the instrument's air chamber to a lower pitch, or if you plan to do tap tuning, we can reduce the size of the apertures by 1/16" on special request.
To ensure their precise shape, the apertures are fixture routed. This photograph is of the f-hole on an F5 mandolin.
The inside of the soundboard is gauzed before the apertures for the A5 and F5 mandolins and H5 mandola are cut. Aside from providing strength to the delicate edge of the soundboard, the added stiffness inhibits any damping that occurs as energy is wicked-off at the thin edge of the soundboard.
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