Steel Trusses for Masts.

South Canterbury Times, Issue 6237, 9 June 1890, Page 3

Steel Trusses for Masts.

There is no problem of greater interest to shipbuilders and owners along the Atlantic Coast just now than that of devising a safe and otherwise satisfactory rig for the big four masted schooners that have become so fashinable within the past three or four years. Instead of the long thick heavy spar rising from the midship line, it is proposed to substitute two neat, substantial steel trusses. The trusses are to be built of three or four pieces of flat steel set edgewise to the side of the ship, and united by angle irons riveted between them and by tie rods, which would make the truss at once light, stiff, and symmetrical. Where the truss'.a meet at the orosstrees, they would be riveted to a stiff steel cylinder, in which the topmast would be stepped. From the heel of this topmast, or from the steel cylinder in which it was stepped, would be stretched a steel rope, the lower end of which would be set up in a stout eye-bolt set into a deck beam. The sail could be secured to this perpendicular slay by clips, just as the yacht jibs are secured to a jib stay. The boom and gaff would swing on metal collars put around the rope. The sail would swing to and fro as readily as it now does. The steel rope on which it swung, if of proper size, would stand a much greater strain than any wooden mast. Further, to strengthen the trusses that at once replace masts and shrouds, cross-plates and tie-rods could be run from truss to truss, but if tho trussplates were made of suitable size, and the size could be easily calculated, these long tiereds would not be necessary.