Abstract: A method of enlarging a ring. A ring to be enlarged is severed, preferably with an end mill, and then expanded. The end mill will preferably cut a circular section from the ring, so that the ends of the now severed ring are concave. A plurality of preformed bars are also provided. The bars will have curved ends that match the curvature of the ring ends. The curvature of the bars and the ring will also match. The width of the various bars, between the ends, will be selected to correspond to desired increases in the ring circumference. A cross-sectional slice will be cut from a bar of the appropriate width and inserted into the severed ring. The ring and the cross-section will then be joined together, preferably with an induction welder, which can be used to quickly heat only a limited portion of the ring and insert.

Abstract: Apparatus and methods for making uniformly-sized and predictably-spaced droplets from high-temperature liquids. Liquid droplet generators having electromechanical driving elements are coupled to a power supply to apply pulsed excitation forces through a wall of a delivery tube to a high-temperature liquid, e.g., a liquid metal, epoxy, or polymer. The excitation forces generated by the driver induce capillary vibrations in the liquid within the delivery tube. Liquid jet streams having capillary vibrations when exiting an orifice break up into groups of substantially uniformly-sized liquid droplets shortly after leaving the orifice. Droplets may be produced in a uniformly-spaced series, or individually on demand in response to a single burst of force from the driving element. A heat source is also thermally coupled to the delivery tube to maintain the liquid in a high-temperature state.