Real Lyre for Stwy XO

[william ballard]

I'm getting ready to retrofit an 1897 Stwy lyre onto a (somewhat  
later) Stwy XO. I have to work out all the details in advance because  
the piano is at a summer chamber music program which has four-day  
breaks every other week. For reference there is a 70s L and a 100-yo  
O in the same building, and two Bs in the next building. But I'm  
collecting what common sense may already exist on a piece of work  
I've never heard  of being done.

It's just a matter of careful layout, right? I'm ordering brand new  
levers from the factory.

So, a couple of preliminary questions:

1.) The keybed and keybed stiffener (the plank of solid, straight- 
grain softwood, 1-3/4" thick which the lyre is mounted on/under). Is  
there any real purpose to the stiffener plank, say allowing the trap  
lever contact points to be above the top plate of the lyre? Or more  
to the point does whatever purpose may be require material of a  
particular strength (say, Marine Plywood).

The XO's keybed is 2-3/8". There is no stiffener (outside of an iron  
I-beam bolted to the underside of the bed). If a stiffener plank is  
there only to add rigidity, then I can simply find a proper location  
for the existing I-beam in the new layout of things. If it's simply  
to properly locate the lyre vertically with respect to the floor  and  
the pick-up points on the trap levers, then I think that two layers  
of 1/2" fir plywood painted black would serve the purpose. (The extra  
thick XO keybed is 1" thinner than the combination of keybed and  
stiffener.)

2.) The keybed and the U.C. shift lever. The XO keybed is 3/4"  
thicker than the standard Stwy keybed, so my plan to avoid a shift  
lever short arm 5/8" below the top side of the keybed is to slice the  
3/4" off the wooden pivot mount blocks. I can't see that it would  
weaken them, each of them being held fast to the underside of the  
keybed with a pair of #18 wood screws.

3.) The initial locating of the lyre (ie., where you inlay the female  
locking plate). Not knowing any more about it, I'm guessing that the  
front-back should be located by the sustain pedal pitman. (I'm having  
to drill a fresh hole for it as the original sustain pedal lift for  
the Duo-Art was way down at the bass end. I'm guessing the exact  
location left-to-right for the pitman is arbitrary.)

I'm also guessing that the lyre's L-R location will be determined by  
the U.C. shift lever, and guessing that when the lever short arm fits  
into the slot in the keyframe, that the long arm should position the  
lyre nearly/exactly in the middle of the keybed. I am prepared to re- 
locate the slot if I have to.

4.) the U-bracket on the Sostenuto rail is down at the bass end  
(along with the sustain pedal pitman). I'm not assuming that  
extracting the existing U-bracket and relocating it to the usual bass- 
break is as easy as it seems, and so I'm prepared to spring for a new  
L sostenuto rail.

Anyone done this before? Any thoughts from anyone? On the day that  
all this gets down, both the XO and the O upstairs will be on their  
sides (the latter, for quick reference).

TIA

Mr. Bill