Gordon and list, Gordon wrote; > . . . the plate is out . . >. . . and I'm replacing the agraffes >. . Two original agraffes broke >. . Oops!! Stripped the threads in the plate. >. . Any hints? We have had success with the following; A threaded sleeve (with an inner and outer thread) is turned up on the lathe. The sleeve ID is tapped to match the thread of the agraffe. The sleeve OD is then turned to 0.375". A 3/8" UNF (24 threads per inch) is turned onto the OD of the sleeve. The outer sleeve-thread will have a minor diameter of 0.324". If the agraffe thread is 7/32" OD, the threaded insert will have a wall thickness of 0.053". There will still be sufficient wall thickness when the agraffe is a 1/4" thread by 36 TPI. However, it is important that the inner thread is tapped prior to turning the outer thread. If the order of operations is reversed, there is a risk that tapping the inner thread will stretch the sleeve OD, making it difficult to fit it to the plate by hand. After drilling the original agraffe hole with a tapping drill of 8.5 mm, the hole is tapped with a 3/8" UNF tap. After applying a thin coat of locktite to the thread in the plate, the threaded insert is wound into the plate. The agraffe is then fitted to the plate. This repair is very effective. Regards, Ron Overs -- _________________________ Website: www.overspianos.com.au Email: ron@overspianos.com.au _________________________
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