The gallery below shows an extensive documentation of the restoration process. If you click on a picture, you will get a larger view with an explanation below.
This instrument was most likely built by the Tonk Brothers for Washburn. Its manufacturing date should be somewhere around 1925.
1. Tuning Issues
This mandolin was unplayable due to its fret placement. The fingerboard had fret slots based on the traditional scale (330mm), but surprisingly the top cant was too close (<330mm). Previous owners had tried to eliminate the issue by moving the bridge past the top cant, which potentially introduced some static problems (cracks in the top), and also created some action problems. The best way to address this issue was to accept the flawed cant location and adapt the fingerboard to the resulting shorter scale. Since the fingerboard was in bad shape anyways, a fingerboard replacement became the ideal procedure to make this mandolin play in tune.
2. Cracks & loose braces
The top had many cracks, some of which may have been the result of either aforementioned bridge placement, poor manufacturing or age. These cracks had to be stabilized and closed, to ensure the mandolin will be completely playable without any buzzing. The pictures in the gallery will shed some light on the details. Also, some braces were loose and had to be reglued.
Note: Such repairs can be done from the outside on guitars, but on this mandolin the small sound hole restricted access to the instrument inside. The back had to be removed for these repairs.