At 16:37 -0800 17/11/08, Debra Feiger wrote:
>Thanks for your responses on ivory replacement. JD - What do you use
>to clean the keytop? Do you need to fully scrape off any existing
>wafer or can you put the new wafer on top?
The key top needs to be perfectly clean bare wood and no wood should
be removed. If all you have to remove is water-soluble animal glue
then you're in luck. Dampen the top with warm water, leave it a few
minutes and then wipe it clean with a warm damp cloth. You might
have to repeat this process several times but it is easy work and
time does most of it.
More often than not your predecessor has not been so considerate and
you will first have to remove great daubs of some unspecified
chemical adhesive. If it's hard and scrapable then you can scrape
most of it off and then finish by using acetone or cellulose thinners
(or anything that will work) to dissolve it. With luck your
predecessor will have been lazy enough to apply the chemical on top
of the old animal glue, so once you have removed his gunk you can go
back to line 1 and wash the key clean.
When the wood is dry, test the ivory head against the tail and, if
you have the choice, choose a head that is just a hair's breadth
thinner than the front of the tail, the difference to allow for the
thickness of the glue line. If there is a big step up to the tail,
test it with a dry wafer underneath. Wafers, as I said before, are
rarely used, at least in Europe since about 1880, in production work
and over here most tuners over the years have used the nearest old
tube of whatever disgusting chemical they have at the bottom of their
bag to stick the ivory back with their dirty fingers.
Even with lots of experience it's difficult to get a perfect result
first time every time. I often wonder at the skill of the old key
finishers from the head-an tail days and it's a great pity they're no
longer about to let us into all their secrets.
JD
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