Abstract: A sheet metal, elongate structural member is cold roll-formed from a strip of sheet metal no thicker than 1.2 mm, preferably 0.6 mm, including a central zone and two edge zones flanking the central zone and each having a free edge margin. The member includes a substantially planar web (9), a first hollow flange (10) extending along one edge of the web (9) and projecting laterally to both sides of the web, and a second hollow flange (11) extending along the other edge of the web (9) and projecting laterally to one side only of the web. The web (9) includes the central zone and the margins (17, 23) of the original strip secured flatly together by clinches (18, 29), and the hollow flanges are formed from the edge zones of the original strip excluding the margins thereof. The spacing of the clinches is selected so that the shear point of the member's section substantially coincides with the plane of the web.

Abstract: A structural spacer adapted to bridge between two stringers each comprising a web pierced by a pair of slots of predetermined size comprises a steel channel-sectioned body (10) with pressed metal end fittings (11,19) at each end. One end fitting (19) includes two projecting, relatively small hooks (24) with arcuate outer surfaces (25), adapted to respectively engage an edge of the slots. The other end fitting has two relatively larger hooks (14) with arcuate inner surfaces (15) adapted to enter the respective slots and engage over the small hooks of a second spacer engaged therewith. The depths of the large hooks progressively increase from a minimum at their tips, so that when the spacer is swung into the operative position, but not before, the two hooks extending through each slot substantially fill it. An abutment (18) on the end fitting with the larger hooks determines the extent to which the spacer may be swung as aforesaid.