has been loaded, scrape up a little dirt that will push theobject back further into the bowl.To unload the object, shift the ejector from forwardto reverse several times to move the object around so itwill fall out. After the object has been unloaded, turnthe tractor sharply so the scraper clears the unloadedobject.NOTE: Use extreme care when handling largeobjects. Oversize objects, such as large rocks, can causedamage by denting, bending, or straining parts. Damagemay also be done by accidental collision with large rocksduring ordinary digging.PRODUCTION TECHNIQUESScraper production techniques are used to achievethe most amount of work with the scrapers assigned.These techniques are as follows.Figure 10-44.-Straddle loading.Downhill LoadingDownhill loading uses the force of gravity on thescraper to get larger loads in less time. The added forceof gravity is 20 pounds per gross ton of weight per 1percent of downhill grade. The downhill pull adds morematerial per load, and the added material weightincreases the total gravitational pull.Straddle LoadingStraddle loading gains time on every third tripbecause the center strip loads with less resistance thana full cut. After the first scraper has made a cut, thesecond scraper should make a parallel cut and leave a 4-to 5-foot-wide island between the two cuts, as shown infigure 10-44. The third scraper can straddle this islandof material to achieve a fast, less resistance load.Back-track LoadingBack-track loading is the method where the cut isfairly short and loading in both directions is impractical.As shown in figure 10-45, too much time is spent backtracking and maneuvering the push cat for the next load.When the cut is wide enough, other methods should betried.Shuttle LoadingShuttle loading is used for short cuts where it ispossible to load in both directions, as shown in figure10-46. The push cat pushes one scraper in one direction,then turns and push loads a second scraper in theopposite direction.Figure 10-45.-Back-track loading.10-24
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