Richard Callis’s love affair with the mandolin grew out of a piece of bad luck.

A longtime bluegrass singer, the Mathews resident played the guitar for many years. Then he began having pain in his shoulder, and he found out he had developed a rotator cuff problem. He could no longer extend his arm up the neck of the instrument, ending his days as a guitar player.

But one day when Callis was in Winter Sound, a Gloucester Point music store, he came across a low-cost mandolin and decided to take it home. He discovered that the smaller size and shorter neck of the instrument posed no problems for his shoulder, and he’s been playing one ever since.

The only problem with playing the mandolin, said Callis, was that a good one was much more expensive than a guitar. He didn’t like the sound or the looks of the mandolins he could afford, so he decided to build his own. In 2008, his wife gave him a book on constructing a mandolin, “The Ultimate Mandolin Construction M...