[CAUT] Knuckle Direction

[Ron Nossaman]

Jim Busby wrote:
> Hi Paul,
> 
> I've heard both arguments "this way and the jack slips out
> better" and "that way and it gets returns better,
> especially on a soft blow". In a class I took years ago
> (can't remember who but he was good, and it made sense) he
> said his company did a lot of testing and it didn't seem to
> matter, but that they all should be the same.
> 
> That being said, I just looked at some new Renner knuckles
> and they are installed so that the jack goes OUT with the
> grain and returns AGAINST the grain. To me this is
> counterintuitive. I looked at another piano and they were
> backwards from that. Go figure.

It's yet another of the many "intuitive" things we worry 
about. I'm in the "doesn't matter as long as they're all the 
same" category. The reason being that in play, the jack is 
being pushed away from the knuckle on return, and isn't really 
dragging whichever way the nap points.
Ron N