Ebony finish, round two

[John Delacour]

At 11:51 -0500 2/1/08, Ed  Sutton wrote:

>Now, the question:
>I have adopted an 1892 Mathushek upright piano. Originally it had an 
>ebony finish, but was stripped and stained mid-20th century. I'd 
>like to return it to ebony.
>What were the common methods of producing ebony finished in the 
>1890's?  Are any of them suitable for use by an ignorant operator 
>with a small shop without
>spray equipment and skills?

The method used in Europe was French-polishing, and that's how I 
always finish black pianos.  You can buy ready-made black polish 
(here) but I always suspect they use whatever suits them in the way 
of shellac because nobody can see the quality of the original polish, 
so I buy clear polish of the quality I want and mix in a solution of 
spirit black in spirits.

Spirit black gives the proper black, which is in fact a deep 
transparent purple.  It's important to get the colour right.  Nothing 
should be used that contains carbon black, since this does not give 
the deep "piano black" that is required and looks grey in comparison. 
Most so-called black paints are soot-coloured.

If you can French-polish, you're most of the way to doing a glass 
finish on black, but the finishing is the most difficult part, since 
the slightest wave or blemish will show so much more on black.  It is 
normal to use clear polish or "white polish" for the finishing 
rubbers.

One thing I would warn against is French polish on a maple substrate. 
Thankfully very few makers in Europe used maple veneer for black 
pianos but Steinway were an exception and I am unfortunate enough to 
have two of these to finish.  Like beech, maple will not hold a 
finish for very long without problems in my experience.  If there's a 
secret I'd love to hear it.

JD