Page 35 - Moving the Earth_ The Workbook of Excavation

LAND CLEARING AND CONTROLS

LAND CLEARING AND CONTROLS 1.35

FIGURE 1.26B Take-up block.

The final stump may be pulled by use of a living tree as an anchor. A choker should not be used
under any circumstances on a tree which is to be preserved; padding and blocks should be used with a
grabhook loop.
If no anchor is available, one may be made, ground conditions permitting, by digging a
T-shaped trench, 2 or more feet in depth, as shown in Fig. 1.27. A log is placed in the crossbar,
the cable anchored to it and led up through the sloping trench toward the work. Load and local
conditions will determine the depth of cut and size of log. In medium soil, a standard railroad tie
2 feet down should hold a horizontal pull of 5 tons. This is sometimes called a “deadman.”
Advantages of Blocks. Stump pulling with a winch and blocks takes more time and care than
direct winch pull, but results are generally more satisfactory. Jerks and jars which are destructive
to machinery and cables are largely eliminated. Lighter cable may be used, and a sufficient num-
ber of lines will reduce the tension on any one so much that squeezing and crushing on the drum
will not occur.
A snatch block may be used to advantage with an anchored winch to avoid shifting its direction for
each stump. Figure 1.28 shows a plot in which a number of scattered stumps are to be pulled. A snatch
block is anchored to one of them, and the line led through it. The line can then be attached to stumps

FIGURE 1.27 Artificial anchor.