Piano Bridge Duplication

Following is a picture tour of a critical aspect of piano rebuilding – piano bridge duplication. The instrument shown is a Steinway Model M baby grand piano. The bridges being replaced are not the originals.
Several methods are not described here since they are proprietary. This does not necessarily mean that I keep secrets, in fact most of my processes have been demonstrated in clinics over the years. My main concern is that the information I present is not interpreted as DIY tutorials. Piano bridge duplication is a critical part of piano rebuilding, requiring advance training. If a piano bridge duplication is done incorrectly or not included as part of piano restoration that the instrument will not function optimally.

DSCF0419Inspection of old bridge shows failure in the structure supporting bidge pins. This results in failure of intonation, tuning stability, and longevity.

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Removal of old pins before routing

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Taking precise measurments of old bridge for consideration in establishing new bridge height.

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 Paper transfer template provides location of bridge pin holes. This become the blue print for accurate piano bridge duplication.

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Routing of bridge cap down to vertical bridge base form.

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Bridge base after routing.

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New cap blank rough-cut on band saw

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New bridge cap blank thickness roughed-in on belt sander.

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 New bridge cap blanks ready for instalation

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New bridge caps after being adhered to bridge base
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New caps scribed for drilling after precise height was calculated and achieved

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New caps drilled for bridge pins. Each hole is drilled at compound angle within a given tolerance to pin diameter.

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Bridge notching is done by hand. Piano bridge duplication is a very physical task. Pianos are precise instruments yet not necessarily delicate. Working on them is not always pretty.
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Long bridge after notching by hand

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New bridge cap after notching.

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 Graphite burnished into bridge top

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Bridge Pins being inserted into bridge. After they are inserted pin top are ground. This is the final step in piano bridge duplication.