It's a design feature... Dean Dean W May (812) 235-5272 voice and text PianoRebuilders.com (888) DEAN-MAY Terre Haute IN 47802 -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Ron Nossaman Sent: Monday, January 23, 2012 12:44 PM To: pianotech at ptg.org Subject: Re: [pianotech] broken agraffes On 1/23/2012 10:40 AM, Wally Scherer wrote: > It seems that Steinways are notable for this problem. (WHY?) The agraffes that break have a flat bottomed shoulder and the stud isn't threaded all the way up to the shoulder. When these were installed, the stud ran out of thread before the shoulder seated, so they just cranked them on down in spite of it. This over stressed the stud. When they did bottom out, the flat bottomed shoulder wasn't crushable like the concave shoulders in the supply house agraffes we get now. So when they cranked them even harder to align them it stressed the stud even more. When they eventually break, the stud threads are still jammed into the plate threads, making the broken stud hard to get out. That's pretty much it. Ron N
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