. The railroad engineer's practice . allowed be-tween diameter of bolt and hole. Thickening washersmast be used whenever required to make the joints snugand tight. All iron musb receive one (1) coat of boiled linseed oilbefore leaving works. All inaccessible surfaces are to bepainted, preferably at the bridge site during erection, withone (1) heavy coat rel oxide of iron in pure linseed iron to be scraped clean from saale before painting. GENERAL CONDITIONS. * The whole of the construction to be first-class work, andin strict accordance with the drawings and these specifi-cations. In t
. The railroad engineer's practice . allowed be-tween diameter of bolt and hole. Thickening washersmast be used whenever required to make the joints snugand tight. All iron musb receive one (1) coat of boiled linseed oilbefore leaving works. All inaccessible surfaces are to bepainted, preferably at the bridge site during erection, withone (1) heavy coat rel oxide of iron in pure linseed iron to be scraped clean from saale before painting. GENERAL CONDITIONS. * The whole of the construction to be first-class work, andin strict accordance with the drawings and these specifi-cations. In the case of sub-contractors, the specificationsare fully bin ling on them in every respect, and free accessand mformition is to be given by tliem for thorough in-spection of material and workmanship, and all requiredtest pieces, etc., are to be provided as may be requested. 82 In all cases figures are to be taken in preference to anymeasurements by scale. No alterations are to be made unless authorized bv the engineers. TRESTLE The above is |the usual form. The bents, or atleast some of them, should be Aveil braced togetherwith 6 X 12 stuff, and placed about 10 feet more than 15 feet high, make it in two or morestories. The posts are generally mortised into the cap andsill pieces. In such cases if the mortise for the lower tenonis not cut entirely through, a hole should be bored to letthe water out which will collect in it. Some engineersconsider it better to cut no mortises or tenons at the lowerend, bill, to make the connections with wooden dowel pins,two to each post, to prevent twisting. These should belarge enough to fit tightly in a three-inch hole. The in-clined posts should be cut oil square, and rest in shoulders^ut in the cap and sill. Iron straps may then be used toketp all secure. When a mortise and tenon are used, the width of thetenon may be made from one-third to one-fourth the width 83 of the stick. A tree-nail passes through both mortise andten
Size: 1734px × 1440px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, bookcentury1800, bookdecade1880, bookidrailroadengineer00clee
