Hitch Pin Replacement Question

[Will Truitt]

Hi Jon:

You mentioned that you replaced only the bass and tenor section hitchpins
with a vertical hitchpin.  Why not the whole enchilada?
Am I corrected in surmising that the piano on which you left the treble
hitch pins alone had rear duplexes?  If so, how did you set bearing
combining the two techniques? What was your reasoning in keeping the rear
duplexes?

I have done one set of bass bridge hitch pins changing to a vertical hitch
pin.  I followed Ron Nossaman's advice and sheared off the old hitch pins
with a cold chisel.  Took all of 10 minutes once I got going.  Then center
punched and drilled the vertical holes with the plate under my drill press.
Once I overcame the fear factor, it was actually pretty simple and
straightforward.

Will Truitt


-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Jon Page
Sent: Sunday, July 13, 2008 7:11 AM
To: pianotech at ptg.org
Subject: Hitch Pin Replacement Question

I've done only one hitch pin replacement so far but limited to the tenor
section and bass. The tenor was easy by punching the pins out from
underneath but the bass was a problem. Trying to pull them out often
resulted in breaking them. This left a jagged surface which needed
grinding on the ones which didn't break below the plate surface.

Be prepared to go through many bits while drilling. Start smaller
and work your way up to the desired diameter.

The tenor section was drilled at an angle so I needed to force in
MarineTex paste epoxy from the bottom, let it cure and drill straight
down from the top to install vertical hitch pins.

Some of the plate risers will have to be ground for bearing clearance.
You may or may not be surprised at what factory surfacing produced,
I usually find it too high in the low tenor for a few inches on the right
side of the lower strut.

I am a fan of vertical hitch pins.
-- 

Regards,

Jon Page