[pianotech] Brass rail

[John Delacour]

At 16:45 +0000 26/5/10, Barb Nobbe wrote:

>...I do plan on replacing all the tabs and little screws with the 
>rebuild, as it's getting new hammers and butts too,  but I was 
>hoping to save the cost of duplicating the rail. I know OTOH, that 
>brass is a really soft metal and if one of the tabs on the rail 
>breaks off, I've got a nice little headache to have contend with.
>
>Should I save myself the possible headache, cough up the extra dough 
>out of my budget and go ahead and get a new rail, or would most of 
>you take the chance on keeping the original?  Just curious. Thanks!

The problem with brass is not that it is soft but that for one reason 
or another it can become very brittle in certain environments or 
after a certain time, and there's no way of knowing if it has until 
something breaks, usually something irreplaceable.

I am pretty sure that this brittleness can be removed by a controlled 
heat treatment process, which would cost very little; but perhaps 
there is an engineer reading the list who can confirm this.  If not, 
I'd get in touch with a local engineering firm and have them put you 
in touch with a specialized heat treatment shop and ask them for 
advice.  If they're not familiar with the question, carry on until 
you find a firm that is.

JD