It's probably a Whitworth thread. ½" x 12 tpi. Gotta love them Brits. Kawai used Whitworth until 1971 and then went to 12 mm x 1.75 tpi.
You can get the new fasteners from Kawai or I have more than I'll ever use, Just need to know the length of the bolt; 70 mm or 90 mm.
Square head, hex head or cap screw (hex key). Replace both, then you'll have the old spare Whitworth parts for the next repair.
If you have the Moon Dog Grand Piano Tilter, you have the bolts to compare/determine threads.
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Regards,
Jon Page
mailto:
jonpage@comcast.nethttp://www.pianocapecod.com------------------------------
Original Message:
Sent: 09-16-2021 17:03
From: Terrence Farrell
Subject: Screw Attached Nut Question
I am repairing a leg on a not-real-old Wurlitzer fetal grand. The owners moved the piano by pushing it - and yup, broke the rear leg off. Two cast iron nuts that the two leg bolts screw into broke in half. Does anyone know what that nut is called (what type)? It is held in with four smaller screws. It fits a 1/2" diameter machine screw. Anyone recommend a good place to look for one?
Thanks!!!
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Terry Farrell
Farrell Piano Service, Inc.
Brandon, Florida
terry@farrellpiano.com
813-684-3505
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