Seamless Tubing in Brass Musical Instruments

Like most industries, brass musical instruments benefitted greatly by advances in technologies of the industrial revolution. The invention and constant improvement of chromatic brass instruments, aside from the trombone, which pre-existed, but also saw improvements, happened in this era. This was made possible by materials, tools and processes developed during this expansion of human understanding of the world they inhabited and how to exploit it. While musical instrument makers capitalized on the advances in other industries as best they could, but it was never to be a sector that would lead in those advances. Production of textiles, iron and steel, machine tools, agriculture and advances in communication and transportation, being universally desired and demanded, would be the leading industries, but development of smaller demand markets also progressed.

This introduction is background for the question that this article attempts to answer or at least shed light on with informed speculation. The puzzling question is: Why was the musical instrument industry so late in adopting seamless tubing? The easy answer is that tubing with seams worked just fine and it wasn’t worth any additional effort or cost. But why would it cost more or be difficult to obtain? Seamless brass and copper tubing was first developed on an industrial scale and patented in 1838 by Charles Green in Birmingham, England. This was a great improvement in boilers for steam engines that had previously relied on iron or brass tubing with soldered or brazed seams the length of each tube. Seamless brass tubes were superior, tolerating higher pressures and needing replacement at longer intervals. The demand was strong and by the mid-1860s, 85% of all steam engines in England were powered by boilers with seamless brass tubing and quickly spread to all of Europe and the United States. American Tube Works was in full production of seamless brass tubing for steam boilers in Boston by 1851 and were also widely promoting the superiority and lower cost for water supply in residential and commercial plumbing in the 1860s.

The earliest that seamless tubing is observed in musical instruments is in brass ferrules that reinforce the ends of wooden fifes. The year of manufacture can’t be determined on most of these, but the seamless ferrules are seen on fifes by Firth, Pond & Co. of New York made before 1863. but not seen in brass instrument tuning slide tubes until ???? It is possible that fife makers were able to obtain short pieces of seamless tubing that were trimmed from longer tubes as they were installed in boilers or utilize old boiler tubing when removed from service. When boilers were in constant service in both locomotive and stationary applications, the brass seamless tubing would need to be replaced about every three years. The more likely explanation is that these short brass tubes for ferrules were produced using the same method as firearm cartridges. This involved pressing and then drawing them from a disk cut from a sheet of brass, annealing before each step. In 1858, Alexander Parkes of Birmingham, England was granted a patent for using this technique for making longer seamless copper, brass and nickel silver tubing. It states that “the thickness of the original discs are to be proportioned to the length and thickness of the metal of the finished tubes”. It doesn’t clarify if this means that the center of the disk is thicker than the outer edges or just overall thickness. In the latter case, the tubes wall thickness would be far greater at the open end the closed end formed from the center of the disk and would require more force and additional drawing steps to result in uniform wall thickness. The patent does not specify the lengths of finished tubes, but certainly long enough for making brass instrument tuning slides.

The seamless tubes needed for steam production were typically six to eight feet long. These were produced by first casting a short, thick-walled tube that was then drawn longer and thinner, annealed, and the process repeated, typically five times, until they were the dimensions needed. Flaws in the initial casting wouldn’t be found until they failed during one of the subsequent drawing steps, which added to the cost of this process and added incentive to improve alloying and casting technologies. Another innovation from this time was to make the final draw onto a mandrel with a slight taper, so that the tubes wall thickness would be greater at one end. This end was installed closest to the firebox, and would last longer before leaking and needing repairs and ultimately replacement.

By 1866, six factories in Birmingham, England were producing 6500 tons of seamless brass tubing each year. These same factories also produced brass tubing with seams, presumably at lower cost. Even small makers, such as Graves & Co. of Winchester, New Hampshire had draw benches to produce tubes in the sizes needed for their production, but sources have not been found stating whether musical instrument makers made these sheet metal or tubes produced in these large factories as has been the practice since about 1900.