[pianotech] Cleaning Very Old Plate (now string cleaning)

[Douglas Gregg]

Thumpe,

All I can say is you are a brave man. I use Brake cleaner as a solvent
for cleaning brake parts and sometimes carburetors and metal parts
that are really greasy. It is an incredibly strong mixture of
solvents. It is probably the strongest solvent mixture that you can
buy. It will take off paint, lacquer, and most other finishes except
polyester. I don't doubt that a slight drip would remove some finish.
The fumes are horrendous too. I only use it outside in the driveway
with a breeze blowing.

However, your thinking is good. Removing grease, tar, and nicotine
from strings makes them sing again.

Another Method for string cleaning:

Try this method that I discovered following a small experiment with CA
glue. In my home piano (a very old Horace Waters with an ornate case)
I had a buzzing bass string that would not respond to any of the usual
treatments. So I figured I would have to replace the string but first
I would experiment a little. After all the patient is terminal- right.
I put a drop of CA glue on the end of the string where I thought the
wrappings might not be tight. Well, it totally killed the string. Then
I thought, what would dissolve the CA glue. Well, not much. I tried a
variety of strong solvents. No dice. Then I figured, what is dry CA
glue but polymerized acrylic plastic. Plastic will burn. So I took out
my handy propane torch and sure enough it lit up like a candle. Then
the string sounded better than when I started- no buzz and brighter.
So I torched a little more or the string and it got brighter, and then
the whole string. It eventually sounded like a new string. Then the
rest of the strings were very tubby in comparison. So I torched all of
them carefully . They all sound good now. I did not replace any of
them.

What I think happens is that all the contamination burns and smokes
off. Now I have done this in at least a dozen pianos, both uprights
and grands. First I use a wire wheel in a drill to clean the strings
and shine them up. The reason for this is to be able to gauge the
color of the heated copper windings when torching them. Wire brushing
does help the brightness of the sound a little but not much.  I torch
the largest strings first. Move the torch up and down the string to
heat it evenly. Watch the color of the string. It will first change
from bright to an old gold color. This is the time to stop heating.
You don't want to heat it to a blue color. That can kill the string.
Don't ask me how I know. The color change is slightly delayed too, so
stop as soon as the old gold color appears. The small strings are easy
to overheat. I protect the soundboard with a piece of aluminum
flashing behind the strings- the biggest piece that will fit. Mine is
about 1 x 2 feet. I don't bother taking the tension off the strings.
They will go flat and will need to be tuned again but they will be
much brighter.

Method 2

I have been working on this for about 6 years off and on. For this,
you have to take all the strings out and straighten the coils. Bundle
them like a new set. Put the coil in an enamel or stainless straight
sided pot/bucket about 14 inches in diameter. Otherwise, you can't
force the bundle down to the bottom. I then add a 1:1 mixture of
Limeaway(phosphoric acid) and vinegar and two table spoons of
trisodium phosphate detergent or Calgon dishwasher powder in a pinch.
Completely cover the strings with liquid. I then take it OUTSIDE and
put the enamel pot in an electric fry pan and add some water to the
fry pan to make a double boiler. I heat it to boiling for 1 hour. The
strings will look like new. I then let it cool to room temperature and
pour off the acid and save it for next time. Rinse 3 or 4 times in
water in the enamel pot, then add several tablespoons of baking soda
to the last rinse. Let sit for 10 minutes while preheating an oven to
250 F. AFTER the oven is preheated, turn it off, and  put the strings
in the oven to heat and dry. If you don't preheat the oven, the
heating is intense around the edges and will overheat some strings.
Yes,I know. Now it is ready to eat-or rather to restring. The acid is
neutralized by the water rinses and the baking soda and will not start
rusting again. They will look like new strings- even the blackest ones
you ever saw.

Now you know my darkest secret formula.

Doug Gregg
Classic Piano Doc
Southold, NY

Message: 12
Date: Tue, 22 May 2012 19:12:00 -0700 (PDT)
From: Euphonious Thumpe <lclgcnp at yahoo.com>
To: pianotech at ptg.org
Subject: Re: [pianotech] Cleaning Very Old Plate
Message-ID:
       <1337739120.69108.YahooMailMobile at web114719.mail.gq1.yahoo.com>
Content-Type: text/plain; charset="us-ascii"

That&#39;s astonishing!
 I used to clean bass strings by blasting/spraying them ( after
disconnecting the hitch pin end and putting thick plastic between them
and the piano) with brake part cleaner. A large amount of filth would
settle in puddles in the plastic on the keybed, or in folds if a grand
out on the porch, and a nearly "like new" tone and appearance ensue.
(After also running them all through the "Dethubbomator", of course.)
The brake part cleaner left no residue, but, problem was, occasionally
an errant drop of the stuff ( mostly xylene) would leak out onto some
part of the piano where not wanted, creating light spot on finish and
dark mood in customer. And TOXIC!!! (Leaving one unsure of the purpose
of existence itself, for several days, if gotten through or around
even a  top-notch carbon mask. Very, very dangerous!)

  After seeing those photos, I look forward to trying your method on
the built-like-a-tank Mathushek grand I&#39;m now dismantling!

Much thanks!
Thumpe