A back-to-back locator instrument includes a first portion with an array of two or more magnetic sensors, and an indicator arrangement. A second portion of the instrument includes an array of correspondingly located magnets. Each of the first and second portions includes a marking arrangement, which either allows marking of the underlying surface, or viewing of a mark on the surface for properly locating the instrument portion thereon. When the two portions are congruent or registered, the indicator arrangement gives a maximum indication of corresponding locations. In a particular use, corresponding locations on the inside and outside of a tank are identified. The indicator arrangement may include a separate indicator for each magnetic sensor. A flux concentrator may be associated with each magnetic sensor.
A blind spot targeting system for establishing a cutting point includes a locator with a housing having an indicator and a signal-sensing device. The housing has a hole therethrough, and the indicator is in electronic communication with the signal-sensing device for indicating a cutting point on a first side of a structure. A transmitter is also included, which has a complementary hole therethrough. The transmitter is for placement on a second side of the structure for emitting a signal, which the signal-sensing device senses. The indicator in communication with the signal-sensing device indicates alignment of the hole and the complementary hole to establish the cutting point for cutting through the hole into the first side of a structure and possibly through the second side of the structure in a direction of the complementary hole.
A blind spot targeting system for establishing a cutting point includes a locator with a housing having an indicator and a signal-sensing device. The housing has a hole therethrough, and the indicator is in electronic communication with the signal-sensing device for indicating a cutting point on a first side of a structure. A transmitter is also included, which has a complementary hole therethrough. The transmitter is for placement on a second side of the structure for emitting a signal, which the signal-sensing device senses. The indicator in communication with the signal-sensing device indicates alignment of the hole and the complementary hole to establish the cutting point for cutting through the hole into the first side of a structure and possibly through the second side of the structure in a direction of the complementary hole.
