Help with splitting bass bridge

[Jon Page]

Here's my method of bass bridge repair:
What caused it to split?  Either poor wood or the pins drilled in the
wrong place giving too much side bearing, or even up bearing.
I like to start right and measure exactly for the pin position rather
than rely on a possibly rushed factory job.
First note configuration of notches or pin line, make a pattern or
        measure in from edge (for string length purposes only).
Check bearing, at 4 spots - too high (?), too low (?); make note.
        (Chances are it'll be too low making everything easy).
Place a nickle on the plate in front of the hitch pins (or something of that
height) .
        Place the down bearing string on the nickle. Measure height from sound
        board at bridge ends (and center bearing checks - make a notch if
nec.).
        >this is how high it_needs_to be to give proper down bearing.<
Measure thickness of capping material and route enough so you end up with
        your pre determined bridge height. If center needs to be higher,
route to
        that height and adjust ends after cap is glued.
Glue on cap and trim flush, adjust down bearing if necessary.  Don't forget,
        apron flexing; front of cap may need to be a little lower than rear when
        measuring bearing unstrung.
Scribe a pin line or notch line from pattern.
Draw your bearing string from hitch pin to plate pin (or agraffe) and mark
where it
        crosses your scribe. Do that for every string. (Do you think they
bothered at the factory,
        or just used some worn-out template and didn't even get that into
position).
        (Spacing may be *slightly* evened out if prefered, but probably not
on this).
Center punch pin marks and drill.
File bevel or cut notches.
I color the surface with black marker and lube w/ McLube 444.
Drive pins, file tips flat, shellac wood surfaces, have a cup of coffee and
watch paint dry.

I'll probably think of something else I sould have entered, later.

I have even used Falconwood as a cap. I also use 1" pins.
Marine-Tex epoxy is great material. I have plastered it into treble bridge
caverns, let it set,
reshaped and drilled. After 20 yrs, it's still going.

Jon Page
Harwich Port, Cape Cod, Mass. (jpage@capecod.net)
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I'm working on keytop procedure, I'll check the archives and get back.
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At 07:24 PM 1/5/97 -0700, you wrote:
>Hi Bill:
>
>Unfortunately there were a lot of pianos made by a now defunct Co.
>which utilized a softer maple for their bridges in addition to not
>taking pains to maintain good grain direction.  These pianos would
>show splitting in a brand new piano.  How do I know?
>
>Epoxy was little help in those cases.  Recapping with cap at least
>3/8" works better.  It's not that hard to do.  Use a translucent
>or transparent mylar sheet about 2 or 3 inches wide to mark where
>the pins should have been before they bent over. Rout off the bridge
>surface to proper depth (who knows what it should have been?), reglue
>the new cap, remark for bridge pins, bevel edges of bridge (these
>cheap pianos seldom had notches on Bass bridge), re-attach Bass
>strings, seat at hitch pins, chip tune twice, fine tune once.  Is it
>worth it?  Probably not.
>
>Let me correct myself.  Epoxy can work even on those pianos if the
>bridge pin line is routed out about 1/4" wide, completely filled
>with something like marine-tex epoxy, then resurfaced, redrilled,
>etc. as above.
>
>Jim Coleman, Sr.
>
>

Jon Page
Harwich Port, Cape Cod, Mass. (jpage@capecod.net)
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