Many makers have found uses for the telescoping brass tubing from K & S Engineering. This tubing is available in sizes from 1/16" up to 21/32" (modeltool.com is one retail source), and one of the useful features of this material is that each adjacent size telescopes neatly into the next. I use the tubing to make small organ pipes and tuned bicycle horns, generally working with the thin-wall (.014") variety, and I have developed a few techniques to adjust the fit between adjacent sizes, making airtight slip-fits and press-fits of adjustable tension, and also snap-together fits. These techniques all involve stretching or compressing the brass, and they don't involve the use of gaskets or adhesives. Whatever the tubing is to be used for, these techniques might give a maker some useful ideas for future projects.
Len is a longtime friend of The Steampunk Workshop, fellow Wimshurst maker, and the creator of The Majectic Bellophone, among many of accomplishments. - Jake