Counter-bearing drag

[John Delacour]

At 10:10 pm -0400 7/8/07, Jude Reveley/Absolute Piano wrote:

>Ahh, kinda late in the thread, but I've been thinking...oh no!
>
>I'm looking to upgrade my string terminations on my rebuilds too 
>like so manyÊof you cool guys and gals so my questions are:
>
>
>1.	How do bend your half rounds to conform to any required 
>sweep? Clamp in a form?
>2.	Why brass? ItÊis so soft, will get marred by the strings and 
>eventually tarnish?  Why not anondized aluminum or titanium? If it's 
>a question of economics,Êshouldn't we at least plate the brass?

Some makers in the past did nickel plate the bearings and this does 
no harm and might even slightly reduce the already good coefficient 
of friction of the brass.  Electroless nickel would probably further 
reduce the friction (cf Ron Overs' experiments with e.n. bridge pins) 
but plain brass will tarnish no faster than the copper on the bass 
strings, so perhaps you need to consider using plated covering wire 
too as Broadwood and Erard used to.  Brinsmead even had a special 
steel wire drawn for his pianos that was first coppered and then 
either tinned or nickeled and this remains rust-free for over 100 
years -- but nickel goes dull too.  The important thing is to keep 
things spotlessly clean during repair and restoration and advice the 
customer on keeping things clean.  I've just taken in an upright for 
French-polishing from a tuner who strung the piano only a year or so 
ago and then kept it in a shed.  The rust on the steel and the 
wrestpins is horrific and all the copper covers dull and brown.  I 
have no doubt that the shed didn't help but the main culprit is my 
friend the tuner, who will not have worked with gloves and will then 
not have wiped the work clean at the end of the job.  People who 
claim they don't have sweaty hands are kidding themselves -- it's 
just a question of degree, and nothing will cause tarnishing and 
rusting faster than the salt.

JD


-- 
______________________________________________________________________
   Delacour Pianos  *  Silo  *  Deverel Farm  *  Milborne St. Andrew
                      Dorset DT11 0HX  *  England
                        Phone:  +44 1202 731031
          Mobile: +44 7801 310 689   *   Fax: +44 870 705 3241 
______________________________________________________________________