Saturday, September 1, 2018

Antique Cornet Lever Bridge Repair

This antique cornet came across my bench in need of some...remediation. The levers and their clockspring mechanisms are mounted on a bridge, which is attached to the instruments by two feet. One of the feet had broken off and been replaced in a manner that could charitably be described as "haphazard." It was an inexplicably scalloped piece of brass, attached with generous amounts of solder and reinforced with some wire that may have once served a real purpose somewhere as a paperclip. I cut and shaped a new foot from brass, and then affixed it to the bridge with a small handmade brass rivet. A remnant of the original foot provided evidence that this was how it had been attached by the maker. A drawback of using a rivet rather than a screw is that it's more labor-intensive to install and can't be removed without destroying it, but the advantage is that it's very long-lasting and can't be jostled loose over time.

Here's the foot it had when it arrived on my bench, after I'd removed the huge glob of solder that had held it on the instrument, along with a few wraps of wire. The impression from that wire can be seen at the bottom of the photo in some excess solder that had flowed along its length.

Another view of the previous repair. Surprisingly (or maybe unsurprisingly because of how much solder and wire was involved) the joint had held and seemed pretty strong.


Here's the new foot from the underside, showing the rivet that holds it on to the bridge.
 
The new foot from above, contoured to match (well, sort-of match) the style of the other braces on the instrument. The circle visible on the end of the bridge is the top of the rivet.

Side view of the new foot.

All set to go back in to service!