Hi Brian, A while since I've done one of these but from memory: At rest the right angled spring regulates hammer blow height above jack to facilitate return under the notch of the 'hopper'. This may conflict with Rons comment that the hammers sit on the rest rail - I thought otherwise, but I could be wrong. The 'J' shaped spring you mention should not touch the tip of the jack at rest. I think there's a jack spring underneath also. At check the right angled spring holds the hammer against the check with the help of the 'J' shaped one. The force of these two allows the return of the jack upon key release so repetition should be possible without the key lever returning completely. Hope this helps but as I said, it's been a while. By the way it's pronounced 'Blootner' in Europe. Regards Rob Thornton
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