[CAUT] S&S hammer flange rail material

[Fred Sturm]

On Aug 20, 2008, at 6:51 AM, Chris Solliday wrote:

> The one deviation from factory that I do now is add a washer on the  
> top of
> the flange. It helps keep the flange level and particularly keeps  
> the front
> from moving up or down which can alter the centerpin height. I think  
> that it
> is important to maintain that measurement for many obvious reasons.

	Talking about the front of the flange moving up and down, I had an  
early 1980's B I put new parts on last year, and when I had installed  
the shanks and flanges, the fronts were all over the place. Put a  
straight edge on, and there were gaps up to maybe 1.5 mm between the  
highest and lowest. I traced this to bad drilling: the screws were  
angled coming out of the rail, and they carried the flange with them.  
(Put a straight edge next to the screws, and the drilling line had  
about as much variance as the flange level).
	My solution was to enlarge the screw hole a bit fore or aft (angle  
matching the screw's, done with a round file), shim front or back of  
the flange (all the way across, on the curved part), and then I found  
I needed to chisel the top of the flange where the screw bears on it  
at an angle to account for the angle of the screw. Otherwise, the  
screw top would overcome the action of the shim. Not all that much  
work, once I figured it out, but it sure was disconcerting to find. (I  
didn't get it perfect, just addressed the worst culprits and figured a  
wee bit of variation - 0.5 mm or so - wouldn't hurt that much).
	Having those flanges uneven like that makes regulation a little  
strange, especially the drop screws. I had had problems with that  
action all along (original parts), but the most obvious part of it was  
the too short tails (closest possible checking at 7/8" or more), and  
so I never really looked into it, figuring I'd replace parts pretty  
soon.
	Anyhow, it's something to watch for. I've seen it on other Steinways  
to lesser degrees, but this one was amazingly bad.
	I think the new pan head, low profile screws have enough surface area  
to make a washer unnecessary, but some of the old screws have pretty  
narrow heads, so adding a washer isn't a bad idea.
Regards,
Fred Sturm
University of New Mexico
fssturm at unm.edu