A client approached me with the idea of building a slide for a 1930s Kruspe bass trombone bell that was missing its original slide. He wanted something in the visual style of the original, but made with modern parts, and with similar playability to a modern slide. Although the instrument originally would have had no tuning mechanism (other than the handslide itself), no leadpipe, and only a friction fit between bell and slide, we agreed that I would build it with tuning-in-slide, an American-style leadpipe to fit a large shank mouthpiece, and a locking nut between the bell and slide.

I obtained various parts from my supplier, and used a couple of parts I already had in the shop. Here are some of the parts I started out with:




Here I am making the ornamental lines on the braces and ferrules using the lathe. I used nickel tubing for all the braces and ferrules.




A German slide would of course have decorative snakes on the crook. I copied the style of the snakes on the bell, but made them a bit shorter to cut down on weight and to leave room for a stock Bach waterkey in the usual position. The snakes were bent out of small diameter nickel rod. I formed a crook guard from an old nickel slide crook I had at the shop.




Making the little ball that sits atop the snakes:




Soldering the snake assembly together:




Soldering snake assembly onto crook guard:




Putting the outer slide together:



The original slide would have had a "floating" brace where one end of the outer slide brace was not soldered, but allowed to move in and out freely. I decided against this, since the tuning-in-slide design would make for a rather flimsy slide if not soldered, and because I believe the modern way of soldering all the joints with perfect alignment works very well, so I didn't see any reason to copy the older design in that regard. To make the water key look German, I simply lengthened the end of the stock Bach waterkey with some nickel rod.

 Here is the finished product together with the bell. I installed a modern receiver on the bell as well, although I tried to give it the "look" of the original. It's a wonderful old bell in great condition considering its age. You can see the original leather thong actuated valve.