Yamaha used silk chord which is prone to the travails of any organic material. Dental floss is a man make material that is more durable. I have had this problem in the past and have ordered a complete replacement set of flanges. Replacing the flanges is faster than rethreading them. Four years ago they were about $75.00 a set, which is cheap considering the cost your time putzing with string. Newton nhunt@rci.rutgers.edu
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