Burnishing Graphite

[David Love]

Sorry Jon, didn't finish my post before I sent it.

My procedure for easing the back of the jacks is done before the wippens are
installed.  I take one of those shank separators that come with the Renner
flanges.  Cut one to about 4 inches.  On one side a glue a piece of 320
sandpaper.  On the other side a glue a piece of 600 paper.  I hold the
wippen in my left hand with the flange toward my index finger.  With my
thumb I depress the balancier by pressing down on the drop screw leather to
expose the jack.  My ring finger supports the jack on the underside so it
doesn't move.  Use the sanding stick to then take the edge off with the 320
(a couple of light swipes) and smooth with the 600.  Then I touch the edge
with dag applied with the hammer felt.  When the dag is dry you can burnish
by holding the wippen the same way and rubbing it with felt, or you can just
install them and swipe over the balancier with the felt pulling toward the
wippen flange which will depress the wippen as the felt slides by the jack
and burnish the newly rounded edge.


David Love
----- Original Message -----
From: "David Love" <davidlovepianos@earthlink.net>
To: <pianotech@ptg.org>
Sent: August 04, 2002 7:02 AM
Subject: Re: Burnishing Graphite


I've done a similar procedure on Tokiwa wippens (Renners come beveled) and I
think it's a good idea for a better feel during escapement and better return
of the jack under the knuckle.  I don't think you need to spend that much
time burnishing.  When I dag bridgetops I burnish with a piece of hammer
felt.  It doesn't take much to bring out a shine.  Similarly, when I have
done the jacks, I take a piece of hammer felt cut into a wedge (felt mutes
bought from the supply house), press it down on the balancier and just slide
it back toward the flange so that it swipes the back of the jack that has
just been beveled. I use the felt mutes to apply the dag as well.  The
tapered end makes a very nice brush when cut a bit narrower.  A couple of
times over each one goes very fast and seems to be plenty.  The edge will
continue to burnish in playing as the jack slides on the knuckle so I don't
think you need to worry about it that much.  I'm not sure how they do it in
production.


David Love


----- Original Message -----
From: "Jon Page" <jonpage@attbi.com>
To: <pianotech@ptg.org>
Sent: August 04, 2002 6:29 AM
Subject: Burnishing Graphite


I decided to round the back edge of the jacks on a new set of wips prior to
installation.
After meticulously detailing the edge with an emery board (rough then fine)
I gave them two coats of Dag.
Then put a 1/8" drill bit in the Dremel Tool backwards so as to burnish
with the shank.

What a nice job it did, shined up the rep lever too. It got me to thinking
about how the graphite is burnished in production.
Anyone know? It might speed things up for next time.

I was also thinking that using the backside of the sanding disk would
burnish nicely for jacks which have been removed.

As far as easing the back edge of the jacks, is there an easier way than to
file/sand? Would the sanding disk (metal portion)
ease this edge as well or faster than hand working?

I plan to experiment with a larger diameter shank next time, something
along the lines of the arbor on the buffing wheel
after it has been cleaned and polished well.

In any case... I'd like to hear some expedient ways to ease the back edge
of the jack both installed in the wip and freestanding.

Regards,

Jon Page,   piano technician
Harwich Port, Cape Cod, Mass.
mailto:jonpage@attbi.com
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