EDGE-PLANING MACHINE FOR LONG PLATES OF LATTICE GIRDERS; NO. 1 SHED.
_Figs._81_to_83,_Page_40.png)
make a water-tight joint. Nuts were then placed on the holding-down bolts, and screwed down hard with long spanners. As the bolts have no play in the 3-in. holes of this bedplate, the latter becomes thus an absolute fixture upon the pier. The weight of these bedplates is 44 tons each, except those in the fixed cantilevers, where it is 33 tons only.
The projecting parts of the rivet-heads on the upper side of this bedplate had now to be removed, and various means were devised to do this—rose bits, ordinary flat drills, and emery wheels being all tried in succession; but hand-work by chisel and hammer was in the end found to be cheapest.
The various forms given to the recesses in the lower bedplates and to the key-plates fixed to the upper bedplates are shown in the sketch. (See Fig. 88.) In the three piers already mentioned above as the fixed points, a plain circle is shown, and here the key-plate fits the recess exactly without any play. The lined spaces shown in the other piers give an indication of the amount of play between key and recess, and also the direction in which movement can take place.
Thus, in the remaining three piers on Inchgarvie, longitudinal movement alone can take place and a slight amount of circular movement round the centre of each individual pier. In the Queensferry north-west, and Fife south-west, these movements
