Abstract: A universal gear puller that comprises:(a) a cylindrical hub having a central longitudinal hole therethrough, said hole being threaded;(b) a set of three rings, each of which is placed on the cylindrical hub and is at least partly rotatable about the cylindrical hub, said rings being maintained in position on the cylindrical hub by retaining means at the top and bottom of the cylindrical hub, each ring having a pair of parallel members attached to and extending away from the side of said ring, each pair of parallel members having a space therebetween that may be aligned with the threaded holes near the periphery of the exposed end surface of the gear while the central threaded hole in the cylindrical hub is aligned with the threaded hole in the shaft to which the gear is ordinarily bolted;(c) a thrust bolt screwed into said central threaded hole in the cylindrical hub; and(d) a non-threaded means that is long enough to extend to the bottom of the threaded hole in the shaft onto which the gear is ordinarily bo

Abstract: An essentially cylindrical porous blank is formed by the deposition of SiO.sub.2 particles onto the lateral cylindrical surface of a cylindrical mandrel, rotating around its longitudinal axis; this blank is provided with a holding element of quartz glass in the form of a hollow body, which surrounds a section of the mandrel and which is at least partially embedded in the area of one of the ends of the blank. The blank is then sintered. In order to securely support even heavy blanks without complicated holding devices, the holding element is fused into the area of at least one of the ends of the blank during the deposition process by the maintenance of a high temperature.