Abstract: Generally rough sphere-shaped work pieces made of fragile material are ground into more uniform spheres. The rough spheres are fed into a holding plate having a channel cut into the bottom side of the plate with a width slightly larger than the largest diameter of the rough spheres. A movable abrasive surface is positioned adjacent to the bottom side of the holding plate. As the rough spheres move through the holding plate which can be vibrated, they move in contact with each other and with the abrasive surface. The finally formed spheres leave the plate where they are collected. It is a further embodiment green spheres which are treated in a sintering process with hydrogen gas have tungsten oxide particles applied to the surface of the spheres prior to and during sintering so that the particles remain separated and apart.

Abstract: A laminating press for wood products includes at least one pair of heated drums rotating on parallel axes and an endless belt running around the drums, and a device for pressing a stack of materials to be laminated against the belt between the drums, wherein the belt consists essentially of a zirconium or titanium alloy having a thermal diffusivity of at least 0.08 cm.sup.2 /sec and Young's modulus below 20 million psi. Unplated, the belt material provides a non-stick surface with respect to melamine, and because it is unplated, the belt can be resurfaced when worn. Alternatively, the above materials are used in constructing plates for a platen-type laminating press.