Conical/Parallel Fulcrum Procedure

A tube with a conical/parallel fulcrum has the same height at wires I and II; it is “parallel” in this area. From wire II to the butt, the height increases; the tube is “conical” in this area. The conical/parallel fulcrum provides strong resilience.

An easy way to make a conical/parallel tube is to use a single conical (tapered) forming mandrel in a two-step procedure to form the blank. First, insert the forming mandrel far enough so that the intended point on the mandrel is under wire I. For example, you may insert the mandrel until the diameter of the mandrel, where it reaches wire I, is 4mm. Now install wires II and III loosely, pulling only enough to tighten the wires. Use the pliers, from top-to-bottom only, to conform the tube to the mandrel at wire I. For the second step, remove the mandrel so that the 4mm diameter point on the mandrel is now under wire II. Tighten wires II and III again, and use the pliers, from top-to-bottom only, to conform the tube to the mandrel at wire II and wire III. In the area of the tube close to wire III, use the pliers all around the tube, from side-to-side as well as top-to-bottom.