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II

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The bolts, set-screws, pulleys, bearings, shafting and clutches of a plant, although among the foremost factors in its efficiency, are very often neglected until they reach the stage where their condition absolutely compels attention.

ssss1 Contributed to Power by Chas. Herrman.

Very often this lack of proper attention is due to surrounding difficulties of an almost insurmountable and most discouraging nature. At other times it is due to a lack of proper appreciation of the damage resultant from seemingly insignificant neglects. How to overcome some of these difficulties is the object of this chapter.

Fig. 23 shows a case of a turning bolt. The head is inaccessible and the bolt's turning with the nut, owing to burrs or rust, prevents either the tightening or the loosening of the nut. One to three fair-sized nails driven through the timber as at C, hard up against, or, better still, forced into a tangent with the bolt, will often suffice to hold it while the nut is being turned. In iron girders, beams, etc., the nail method being impossible, a slot E can easily be cut with a hack-saw through the lower end of both the nut and bolt, so that the bolt may be held by a screwdriver while the nut is turned with a wrench.