stud's center. Center finders Center stud finders detect the center of the stud by using two sensors that register separate readings of the wall’s dielectric constant. When the two readings match, the finder indicates that it is centered on a stud. The several readings are used to determine the target center. Center finders only need to be moved from one direction. Like edge finders, center finders require calibration. Wall texturing can cause bumpy movement across the wall impairing the calibration readings. Instant stud finders Instant stud finders are a more recent development. Instant stud finders have multiple sensor plates, and do not need to be moved across the wall to detect a stud, overcoming the effects of bumpy wall texture. They use an algorithm to analyze the readings from the multiple sensor plates for a quicker, more accurate indication. Instant stud finders sense multiple regions of a wall simultaneously including the center of a stud, edges of the stud, and regions without studs. Instant stud finders will indicate varied widths of studs and the location of multiple studs at the same time. Because the instant stud finders use multiple readings to determine the location of studs they are also less vulnerable to construction anomalies (such as uneven paint, wall textures, wallpaper, uneven plaster, etc.) that can disorient center and edge finders. Radar scanners The newest stud finders in the industry implement radar technology. Using raw signals transmitted by their sensors, they are able to classify different wall types as well as the material behind the walls. This allows for detection of studs, pipes, wires, leaks and even motion such as pests or rodents. One of their advantages is the ability to work on older houses, such as ones with lath and plaster wall types. References Woodworking tools