It's an Eb alto horn, made between 1876 and 1884. A customer of ours regularly brings in instruments of that vintage that he plays in a Civil War re-enactor band. This one needed a couple of things: First, the bell wire was loose and needed to be soldered in place to keep it from buzzing, and second, the piece of tubing that connects the main tuning slide to the first valve casing was split. On older instruments like this, the tubing is made from a flat sheet of brass with the edges folded up and brazed together, and that seam is what split on this tube. Unfortunately, I neglected to take a before picture, but it looked something like this:
One way to deal with this is to solder a brass patch over the split, which someone had already done on an area of the tube that had split previously. I could have done that, but the first patch didn't stop the split from advancing, and I suspect that a second patch would have only been a temporary fix as well. The better option, then, was to remove the tube from the instrument and rebraze the seam for a more permanent, and practically invisible, repair. After unsoldering the tube from the instrument, I removed and discarded the old patch, removed the excess solder, cleaned up the surface, and brazed the seam with silver solder in exactly the way it would have been done at the factory. Here's a picture of the tube immediately after brazing. The solder is the silver-colored stuff that's pooled on top. It's extremely hard and strong, but has to be very hot to melt - about 1200 degrees. The pink discoloration is a byproduct of the brass being heated to such a high temperature. If you look closely at the end of the red arrow, the line you can see is the seam. The wire is just there to hold the seam shut during brazing.
After brazing, there's a lot of gunk that forms on the surface from the metal being exposed to such high temperatures, so the part gets dipped in an acid bath to remove that stuff. Then the excess solder has to be ground off and smoothed. This picture was taken during that process. Some of the heat varnish remains on the underside of the tube.
Here's another shot, taken further along in the process after sanding. The seam is again barely visible at the end of the arrow.
Finally, after buffing and scratch-brushing, it's ready to go back on the instrument. I scratch brushed it to take away the high shine that buffing leaves, to better match the rest of the instrument, which is 100+ year old raw brass.
Here it is mounted back on the instrument!
Again, from above.
It's incredibly satisfying to resurrect an instrument that's been around for so long, even though I really didn't have to do that much. It plays great, and will hopefully continue to serve for many years.
I'm curious about the mouthpiece. In reading about 19th century alto tubas and Saxhorns I came across mention that a larger cup diameter was commonly used in the 19th century, especially on the 1850s Cerveny original alto tubas in Eb. Is that the original mouthpiece pictured, and is it larger than the modern variety?
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