Fig. 120.
The line E, D, on the diagram represents a tie-rod, which by the construction of this truss would naturally tend to stiffen the structure by supporting the center of the tie-beam.
Wire, nuts, and washers are supplied (where the student makes a whole model) to make the tie-strut.
The student in writing out notes will make two sketches of trusses he may have observed on shop visits. The buildings visited almost all have trussed roofs, either wood or iron.
[A] Definitions from Ricker’s Trussed Roofs.
PROBLEM IN STAIR BUILDING.
Two or three students may work together on this problem.
Read all through before commencing work.
The stair and the hand-rail may be considered as one problem, since the hand-rail forms part of the completed staircase, but they are separated into two distinct problems for convenience in working them out.