Ah, the 70's the era of exploding Ford Pintos, Disco Fever and dubious guitar repair. This 1956 Martin 00-18 recently came in for repair. A receipt in the owners case dates the worst of these repairs to 1976. It’s obviously been through a lot but what is the most egregious is the Gibson adjustable, reverse belly bridge. These bridges were quite common on the Gibson LG series and are now considered as a real tone killer, mainly because the adjustable element is suspended by two 3/8” brass inserts that go through the top.
Using a mirror to look inside shows the real problem. The Gibson bridge was designed knowing that the X brace was going to be at a 95 degree angle, leading to a wide spaced X brace. Martin guitars have always been a narrower 94 degrees so that the brass inserts were installed on top of the all important X brace, cutting it in two. Well, as you can see the “repairman” did glue a short gusset along side the damaged brace, so I guess I can’t be too critical. The top on this guitar has to be replaced so the next installment will cover removing the neck and the top. So stay tuned!