Geoscience Reference
In-Depth Information
make a fire. Some recommended varieties of wood are cottonwood, aspen, yucca, birch, and
poplar. Other woods that work, but not as easily, include box elder, elderberry, and willow.
Note:
Even pieces of the recommended varieties will not work well if they are moist or res-
inous or generate coarse shavings.
The drill should be about ½ to ¾ inch in diameter and about 6 to 10 inches long. The wood
should dent somewhat under your thumbnail, being neither too hard nor extremely soft. Round
the drill end for the fireboard and trim the corners of the drill end for the bearing block at about
45 degrees.
Fireboard
The exact dimensions of the fireboard are not important but, like the drill, the type and condi-
tion of the wood are critical. The fireboard should be long enough to steady with your foot and
significantly wider than the drill; about 1½ to 2 inches wide by a couple of feet long works
well. In a real-life situation, you will use a fireboard many times, until its entire length has been
used up. Using your knife, split an appropriate branch for fabricating your fireboard. Shave
down the round side until it's about ½ inch thick, and then square up the sides. By rotating your
knife tip, make a shallow depression in the fireboard just over one-half the diameter of the drill
from the board edge. This depression must hold the drill as it spins. Cut a narrow V-notch from
the edge of the board to the center of the depression you just gouged into the fireboard. This V-
notch will collect bits of wood shavings, which eventually smolder as you work the drill (see
fig. 7-5
).
Figure 7-5. The fireboard.
Bearing Block
