Standard procedure for my shop is to always replace the agraffes on any piano over 25 years old. This is especially true for older Steinways. The original shank of these agraffes are only 7/32" instead of the typical 1/4" used today. Also the seat of the agraffe is flat which means they were often over stressed at the factory at installation. Add to that the normal weakening of the metal with age, and you have a recipe for failure if they are not replaced. On this piano, something happened that I never experienced before- two agraffes broke while removing them from the plate. Typically they break when they are under tension in a strung piano. It certainly simplifies replacement when it happens in the shop, but it is still a very tedious job because it is very easy to mess up the plate when you are removing the broken stubs.
The first step is to center punch the top of the broken stub as close to center as possible. Also, apply a lubricant like WD-40. Next, very carefully drill a hole in the stub with a 5/32 drill bit. You must be very careful to stay centered as you drill completely through the stub. Drilling off center into the plate is how the plate threads get messed up. After you have drilled through the stub, a #3 easy out is used to turn the broken shank from the plate. I am very grateful that I was successful in removing both agraffes without damaging the plate.
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