Drill bits with predictable walk tendencies

A drill bit adapted to walk predictably during drilling, comprising:

• a bit body having a longitudinal axis and a bit face having a nose, an active zone and a passive zone, said active zone and said passive zone lying within the radius of said nose;
• and
• a plurality of cutters on said face, a first portion of said cutters being positioned in said active zone and a second portion of said cutters being positioned in said passive zone, said first portion of cutters being more aggressive than said second portion;
• said bit face including a plurality of substantially radial blades, at least a portion of one of said blades lying in said passive zone and at least a portion of another of said blades lying said active zone, said passive zone blade portion having a secondary cutter tip profile that is steeper toward said bit axis than the cutter tip profile of said active zone blade portion.

A drill bit adapted to walk predictably during drilling, comprising:

• a bit body having a longitudinal axis and a bit face having a nose, an active zone and a passive zone, said active zone and said passive zone lying within the radius of said nose;
• and
• a plurality of cutters on said face, a first portion of said cutters being positioned in said active zone and a second portion of said cutters being positioned in said passive zone, said first portion of cutters being more aggressive than said second portion;
• said bit face including a plurality of substantially radial blades, at least a portion of one of said blades lying in said passive zone and at least a portion of another of said blades lying said active zone, said passive zone blade portion having a secondary cutter tip profile that is parallel to but offset from the cutter tip profile of said active zone blade portion.

A drill bit adapted to walk predictably during drilling, comprising:

• a bit body having a longitudinal axis and a bit face having a nose, an active zone and a passive zone, said active zone and said passive zone living within the radius of said nose;
• and
• a plurality of cutters on said face, a first portion of said cutters being positioned in said active zone and a second portion of said cutters being positioned in said passive zone, said first portion of cutters being more aggressive than said second portion;
• said bit face including a plurality of substantially radial blades, at least a portion of one of said blades lying in said passive zone and at least a portion of another of said blades lying said active zone, said passive zone blade portion having a gage pad radius that is less than the gage pad radius of said active zone blade.

A drill bit adapted to walk right predictably during drilling, comprising:

• a bit body having a longitudinal axis and a bit face having a nose and an active zone and a passive zone, said active and passive zones lying within the radius of said nose;
• and
• a plurality of cutters on said face, a first portion of said cutters being positioned in said active zone and a second portion of said cutters being positioned in said passive zone said first portion of cutters being more aggressive than said second portion;
• the bit having an imbalance force vector that lies in said active zone.