Columnist John Schmitt expands on his cable-tool string discussion. This month, he talks drive clamps.

Columnist John Schmitt talks dart, flat-bottom and other bailers used in a cable-tool drilling program.

Columnist John Schmitt goes beyond the cable-tool string to discuss other components of a well operation.

Columnist John Schmitt rounds out his discussion of specialized cable-tool bits for particular drilling challenges.

Columnist John Schmitt talks twisted bits, star bits and others designed for particular drilling challenges.

The bit in cable tool applications makes the hole, but it also mixes cuttings so they can be bailed out.

Simple, round steel bar designed to add weight for driving the drill bit.

Drilling jars connect to the socket and enable cable tool drillers to “jar” a stuck string loose.