[pianotech] Agraffe Washers

[David Skolnik]

Certainly valid, however, if we were to assume, for argument's sake, 
that the task-time was basically equal, would there be a reason to 
prefer one method over another?

- Is it assumed that the height of the newly installed agraffe is 
(given proper alignment) correct?
-  Knowing the thread pitch of the agraffe and the degree of 
mis-alignment would seem to provide enough information to rather 
precisely add or remove material.

Ron O certainly finds myriad uses for his lathe, but I wonder what he 
does when working on pianos in the outback.

In answer to Ron N's question: why bother with shims and end 
mills?  the answer is plain.  Because I have them.

David Skolnik
Hastings on Hudson, NY



At 08:29 PM 3/12/2012, you wrote:

>While we're here, I'm still wondering why agraffe washers are even 
>used - ever. For height shims, maybe, but for alignment, neither 
>shims nor end mills are necessary. The use of shims and end mills is 
>predicated on the assumption that THAT particular agraffe is by God 
>going to go into THIS particular hole no matter what!! Why does it 
>need to? I've found that having 10%-15% more agraffes of any given 
>type on hand for a rebuild is sufficient that there will be an 
>agraffe in the pile that will align within reasonable and functional 
>tolerance in each of the plate holes. If you put an agraffe in the 
>hole and find it doesn't snug down in adequate alignment, you have 
>to take it out again to fix it by hoping one of your few stock shim 
>sizes will work, to part off a custom shim, or to guess by feel 
>taking the shoulder down with an end mill. Since the agraffe comes 
>out anyway if it doesn't align in the first hole, try it on the next 
>hole down, or the next. Usually within three holes, it will work 
>without modification or shims. Then you'll get one or two that fit 
>the first time and gain some ground back. With a decent tool for 
>spinning them in and out, it goes very quickly and produces a good 
>job without modifying or adding a thing. It takes me somewhere 
>between 45 minutes and an hour to install a set. Is it faster using 
>shims or planing down the shoulders with an end mill? If you're just 
>replacing one broken agraffe, if you have three or four to choose 
>from, you likely have an adequate match, again, without additions or 
>modification. I really honestly don't get it. Why bother with shims 
>and end mills?
>
>Perpetually baffled in Do-Dah.
>Ron N