A customer dropped his c.1930 Kay Kraft Venetian Archtop off for a setup and I thought I'd take this opportunity to discuss the history of bolt-on acoustic guitar necks and the various attempts to make them easily adjustable for the end user. The other guitar we'll look at was built by Jackson-Guldan. Based in Columbus, Ohio, Jackson-Guldan (J-G) had their own factory and built their own guitars rather than outsource them to Chicago firms. J-G started out making violins in 1915. Beginning about the 1930s they started making some guitars as well, but it wasn't until after the company was bought by Frances Luke Daniel in 1956 that the company began shifting toward a focus on guitars. Daniel had been an employee of Sears Roebuck and probably was aware of the difficulties in manufacturing guitars that could be easily adjusted for good playability. In 1962 he applied for a patent on the process of manufacturing the Adjustomatic Guitars. In 1965 the patent was granted - Patent No. 3,196,730. Bolt-on, adjustable acoustic necks means, in theory, one should never need to reset one's guitar neck because the neck pitch and therefore string height at the 12th fret is adjustable.