New WNG carbon fiber action parts

[Jude Reveley/Absolute Piano]

> Jude,
> 
> Main problems are:  1)  Wippen rail needs to be relieved to clear 
> bottome of wippen, otherwise the rail holds the wippen up off of the 
> capstain.  

Yes, that is correct. I ran my rail through the talesaw at an appropraite angle to get the relief. I then had to build up the risers for the bolts that attach the rail to the brackets. Luckily I foresaw this so it wasn't too much of an inconvenience. 

2)  The Wippen has a cast-in boss for assist springs, which 
> interferes with the hammer tail.  We'll have to cut off the spring 
> boss.  They suggested coving out the hammer a little more, but we'd 
> rather have reliable checking.  

As a general practice I like to custom bore my hammers to account for the string height indescrepencies (and yes this throws off any ideal geometric design). I cut the tails to be consistent throughout the whole set (generally 1") and I also cut my own coves. The inside bottom edge of the hammer tail is also sanded down for weight control and clearance, and I believe this is what you will find on all hammers that have been prepped by the hammer manufacturer. Since this edge is on the other side of the backcheck, it has nothing to do with checking. I believe you''re referring to the radius of the tail. WNG is introducing a jig for arcing tails along with their process of installing backchecks, which appropriately marries the two along with the strikeline. I've beta-tested their system and am happy to report that it's the best method out there for achieving reliably tight checking at all dynamics. 

3)  Let-off button adjustment will be 
> nearly bottomed out - we'll need to replace with longer buttons. 4)  
> Drop screws will be turned down so low they'll be buried - we'll have to 
> install thicker cushion on the rep lever.  As to the suggestion to check 
> the action spread, can't increase it because of the spring boss - hammer 
> tail interference, and can't decrease it or the jack tender will be off 
> the edge of the let-off button.  I'll try to find the photos.  We've 
> test regulated samples of black WNG, new Renner, and the original WNG parts
> in all possible combinations, and the black WNG wippens cause problems 
> in any combination, while the original WNG wippens work best and the 
> Renner wippens are acceptable.
> 

That's an interesting one. If you can't get longer buttons I think you can get longer screws. Steinway has about five or six different options for let-off button sizes. It all comes down to geometry. On my Mason A, we made a new balancerail and custom built the keyboard to match the parts on the topstack. This isn't always an option so you have to figure out what's going to work. Have you checked out the "magic line" at half stroke? This is a new product and let's face it, you're the guinea pig. Me too, so welcome to the club. You can go for it and do what you gotta do to make it work and feel the gratification for pulling it off,  or you can go with a standard part that you've already verified is going to work with minimal fuss, it's your call. IMHO I can deal with the whippen rail modification and the let-off buttons but I don't like what I'm hearing about the drop screws. Something's wrong with the geometry. Can you provide specs for regulation, center heights (rep & hammer), string heights, hammer bore distance, and hammer center to strike?


Jude
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