4 pedals on a Crown

We have 2 Crown uprights that have both had the pedals disconnected and parts removed. The right pedal is sustain. The left is the soft pedal with a compensator. The middle left pedal moves two metal rods up and down in the area of the tuning pins. I am thinking mute rail, but maybe a mandolin attachment or other. The middle right pedal, when depressed pulls down on a metal rod on the treble side that terminates at the height of the main rail. On the back of the main rail approximately 10 inches from the treble end is a hole at approximately the same height as the rod, but not exactly.
Since the parts have been removed, we are unsure what this pedal does or how to hook it up. I would also like to know if the middle left pedal was originally a mute rail or mandolin attachment.
Thanks.

Ben Ereddia

I wish I could answer your question directly. I found this sales catalog in the archive. It describes what the pedals were said to do, but not how the mechanics were laid out

https://picasaweb.google.com/105412259108667869462/CrownPianoByGeoPBent

Thanks Craig,
It's nice to see all the different styles. We have one that is a style 304 in burled walnut. Darn pretty piano. Can't wait to see it when it's finished.

I am starting to get the picture of how these things were set up.
The middle left pedal is for the mandolin attachment/rinky tink rail.
The middle right pedal is for the practice feature. I am thinking that depressing the pedal would pull down on one side of a bar that pivots on the main rail, causing the other end to rise. On the end that rises, would be a rail covered in felt that stops the hammers from hitting the strings.
This is only a guess. If you have any info or ideas, please share.

Has anyone ever seen such a rail?

Yes, many old uprights had such a rail...and many new uprights have them, too.

Thanks Eric.
I have seen plenty of pianos with mute rails.
I have never seen one that pivots upwards from the action rail and blocks the hammers at the shanks.

WOw, a silent rail ! nice idea, may be some trouble with let off ?

ANd when the owner receive a professional pianist used to have 3 pedals "only" ....

I was wondering about let off. Depending how close let off is, the silent rail would have to be pretty precisely located.
Also, would pounding the shanks against a rail, even one covered in hammer rail felt, cause damage?
Again, I am still speculating that this is really how this thing works. I've never seen one. Am I on the right track?

Well think about the "silent" pianos, they all have some foam to allow a shank rebound (and checking, plus certainly better sensations)

BTW it would be easy to add a midi sensor rail under the key if you have yet a system to stop the shanks

I never considered them good for touch, and if regulated too short of the stop rail foam,(a 1mm security is necessary) I suspect the hammer centers can be in trouble.

Regulating and voicing a piano with extra large letoff imply some decisions that can be reversed, but it takes more time than one think (for instance to regulate again a piano that originally had a silent system)

Thank you for the original docs, that is always interesting to see how where designed older pianos

Let-off cannot be set very close in a piano with a silent rail (or a mute rail, for that matter). You are probably looking at 5 mm.

Damage? To the shanks, or the rail, or the felt or??? I don't think so. The amount of playing with it will be limited. Any "effect" pedal is not meant to be in continuous use, otherwise the effect becomes the norm.