Abstract: In order to render honeycomb tables with apertured table leaves clean-room compatible, sealing sheets are provided with projections corresponding in number and location to apertures in the table leaves and projecting into cells of honeycomb cores for a distance being several times smaller than the depth of such cores. These sealing sheets and their projections seal the honeycomb cells against the table leaf apertures inside the table leaves. Debris and lubricant residues accumulate inside these projections during provision of the table leaf apertures and are removed through these apertures preparatory to use of each honeycomb table in a clean room. The apertures are structured for receiving fasteners for attaching objects to the honeycomb tables. A load-bearing sealing structure may be molded from a sealing sheet or may otherwise be provided with cavities situated like the above mentioned projections.

Abstract: In order to render honeycomb tables with apertured table leaves clean-room compatible, sealing sheets are provided with projections corresponding in number and location to apertures in the table leaves and projecting into cells of honeycomb cores for a distance being several times smaller than the depth of such cores. These sealing sheets and their projections seal the honeycomb cells against the table leaf apertures inside the table leaves. Debris and lubricant residues accumulate inside these projections during provision of the table leaf apertures and are removed through these apertures preparatory to use of each honeycomb table in a clean room. The apertures are structured for receiving fasteners for attaching objects to the honeycomb tables. A load-bearing sealing structure may be molded from a sealing sheet or may otherwise be provided with cavities situated like the above mentioned projections.

Abstract: Objects of various sizes are centered and releasably held with a holder member having an annulus and radially mobile object supports or flexible fingers projecting inwardly from that annulus for centering and releasably holding any of the objects inside that annulus. These radially mobile object supports or flexible fingers are of one piece with the annulus. Adjustable actuator members, which may project from an annular structure concentric with, and rotatable to, the annulus, engage the radially mobile object supports or flexible fingers for selectively moving the same radially relative to the annulus for an accommodation of any of the objects. Detents may be provided between the annular structure and the annulus for releasably retaining the annular structure in any of several annular positions relative to the annulus.