I have an institutional contract that includes caring for about a half dozen Kawai UST 9's. The grand style fallboards pivot on brass machine screws that go into the cabinet and they have a tendency to unscrew themselves over time. Routinely, I have screwed them back in on my annual visits but now a few completely unscrewed themselves and the screws disappeared. So now I'm putting a drop of carpenter's glue on the screws in the hope that it will add enough resistance that they won't come loose.
For the record, the correct replacement size is a #4m-.7x16mmmetric machine screw (Phillips flat head). A zinc plated version can be found on Amazon but the brass screws are harder to come by, I ended up getting some from China on eBay. Actually the steel screws are visually passible and the threaded inserts they screw into are also steel so less chance of electrolysis.
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Steven Rosenthal RPT
Honolulu HI
(808) 521-7129
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