Description of Tools

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Hand Drilling Steel

Nomenclature

Rod	The rod is high carbon octagonal steel bar, 3/4 to 7/8 inches wide. Length may vary from 10 inches to several feet.	Star pattern bit
Bit	The bit is the sharpened end of the rod.
Bit Gage	The cutting edge is flared on 7/8 inch steel to a length of 1'/4 inches.* Other thicknesses of rod have similarly proportioned cutting edges.
Effective length	The effective length is the length of the steel that is available for drilling, the total length less the shank or hand hold area.
Shank	The shank is the area near the head where the driller or holder grips the steel.
Head	The head is the end of the rod opposite the cutting edge, and receives the blow of the hammer.	Straight pattern bit
Plastic caps	These are convenient for protecting sharpened cutting edges during transportation and storage. The top cap also keeps ragged edges from snagging other items.
Cutting edge angle	This angle must be precisely maintained during sharpening and reconditioning so the cutting edge remains in the center of the rod.
Bits
Star Pattern Bit	Two perpendicular cutting edges, flared and raised slightly, intersect at the center of the bit. These are common on modern drilling steel.
Straight Pattern Bit	These have a single flared, slightly raised, cutting edge. They are old style bits, and may be found in second hand or antique stores.

*We have not arbitrarily chosen this size rod. Water gels approved for Forest Service blasting are packaged in polyester cartridges. The length of these varies, but the smallest available diameter package is 1 inch. A 1 1/4 inch hole is the minimum size that could easily accept that package.

Description of Tools continued...