Adjusting Action Centers

[Richard Moody]

There is a method of tightening action centers but use at your own risk.
They might come out too tight, or peers might cry "unprofessional".  In
that case consider it experimental.

1.   With a voicing needle poke two to 4 times in the bushing around the
pin.  This is to compress the felt around the pin.

OR

2.  With the smallest hole punch, (like what is used in player piano work)
"Tamp" the bushing.  Press the punch into the bushing so to press it
inwards.

3 Since it is better to have a dull punch,  the "Moody Bushing Tamper" can
easily be made.   Pull the pin out of a center pin punch.  Enlarge the hole
in a drill press to near the size of a #24 center pin.    Bevel the edges
on a grinder enough to clear the wood.

Needless to say for tamping or needling you need to test.  This is best
done by feel, simply flick the the flange (or jack).  The tests given are
usually for hammer flanges but of course not all flanges are hammer
flanges.   But using the swinging tests or the screw drop tests and then
feeling the flange afterwards by flicking or between thumb and forefinger
you can get a pretty good idea for determining the tightness of all
centers.

For those who like to keep records of repairs you might want to indicate on
the flange which bushing you "tamped".   If done by a needle simply  poke a
small mark in the wood near the bushing.  If done by a tamper perhaps a
small circle or dot with a pen or pencil near the bushing.  That way if you
come back and a center is loose , you can see right away if you have
doctored this bushing before.   ---ric


| >
| >On Erard grand from the beginning of the century was this system.
| >
| >Very convenient (individual brass flanges with traditional bushing but
| >adjustable screw for tightness) I've never seen that on other makes,
| >surely a patented design, but I did not find any precise reference about
| >it.
|
| ERARD PIERRE Patent 8643  24th Sept. 1840  Pianoforte.
|
| Barrie,
|
| --
| Barrie Heaton      PGP key on request           http://www.a440.co.uk/
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