A treatise on architecture and building construction . ill mark the bevel of thefoot-cut at the plate. If the rafter is to project beyond the 9 CARPENTRY. 87 plate, mark the foot-cut /// and draw hk at rig-ht angles toit. In the center of Jik draw /;// parallel to Jlj\ then klmis cut out to notch over the plate, and the projection of therafter beyond the plate is measured from Ji towards o. Thelength of the rafter may be determined by setting off thedistance c d along the top of the rafter, once for each foot of half span in theroof, and the cutsat ridge and platemust be made fromthe ends of t
A treatise on architecture and building construction . ill mark the bevel of thefoot-cut at the plate. If the rafter is to project beyond the 9 CARPENTRY. 87 plate, mark the foot-cut /// and draw hk at rig-ht angles toit. In the center of Jik draw /;// parallel to Jlj\ then klmis cut out to notch over the plate, and the projection of therafter beyond the plate is measured from Ji towards o. Thelength of the rafter may be determined by setting off thedistance c d along the top of the rafter, once for each foot of half span in theroof, and the cutsat ridge and platemust be made fromthe ends of therafter so deter-mined. If the spanis 24 ft. and thepitch is the sameon each side of theridge, the distancec fixs, set off twelvetimes from theplumb-cut <7/ to thetop of the foot-cut//, beyond whichthe projection overthe eaves is to beadded, as explainedabove. 154. A veryvaluable append-age to the squareis the simple devicecalled a fence,shown at a in {a). It consistsof a piece of hardwood, preferablycherry or blackp,c CG. walnut, 2 inches. 88 CARPENTRY. § 9 wide, 1^ inches thick, and 2 feet 10 inches long, with sawkerfs be and dc cut in from each end to within 5 inches ofthe middle, thus leaving-10 inches of solid wood at c d. Twoholes /and ^ are bored through each end, and two li-inchNo. 10 screws are then inserted, as shown at /, to bind thefence on the square. The purpose of the fence is to do away with the use ofthe bevel in laying roof joists, angle beams, stair strings,etc. In the above case the fence can be set for the rise ofthe rafter at h i and the run laid off at h k; then, if the fenceand square are applied to the scantling, as shown in Fig. CG(/--), the tongue will show the plumb-cut I in and the bladewill give the bevel for the foot-cut gd. In Fig. GG {b), let eabcdfc be a rafter and hjk a steelsquare with the Iqwcq pq applied for the proper rise and runof the roof. The fence and square are then placed at thelower end of the joist, and the line g d is
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Keywords: ., bo, bookcentury1800, booksubjectarchitecture, booksubjectbuilding
