Abstract: A coating thickness measuring instrument comprising: a magnetic induction probe comprising at least one drive coil and at least one pick-up coil; a driver for driving an alternating current in the or each drive coil; and a detector for detecting the output of the or each pick-up coil; and a processor configured to: apply a transfer function to the detector output to produce an output which corresponds to a measured coating thickness; and, scale both the drive current and detector output simultaneously in response to the output. The scaling may be changed in a step-wise manner. The scaling applied to the drive current may be inversely proportional to the scaling applied to the detector output. The scaling may be defined by a first and second scaling factor, stored as a pair. The instrument may store two or more pairs of scaling factors and select a pair in response to the measured coating thickness.

Abstract: Probes are provided with caps, the caps comprise rolling bearing elements so that the probes can be slid along a surface to be measured, without damaging the surface or wearing away the tip of the probe or a sacrificial cap. The rolling bearing elements can be arranged in a ring around the probe tip, with the plane of the foremost edges of the rolling bearing elements a predetermined distance from the probe tip. The caps can comprise a housing with a grip, to encourage users to grip the cap, which comprises the rolling bearing elements, rather than the probe.

Abstract: A coating thickness measuring instrument has a probe for measuring the thickness of a coating applied to a substrate and producing an output relating to the measured thickness; a memory storing calibration data; and a processor arranged to process the output produced by the probe, together with calibration data stored by the memory, and produce a coating thickness measurement. The memory stores at least two sets of calibration data, each set associated with a different surface profile value and a user may select the set of calibration data to be used by the processor according to the surface profile of the substrate on which a measurement is to be made. This enables a user to make coating thickness measurements on substrates with at least two different, known, surface profiles without having to calibrate the instrument specifically for those surfaces.

Abstract: A surface profile measurement probe comprising two spaced apart points 20 for contacting a convex surface to be measured and a straight edge or surface 22 moveable relative to the two points to enable the straight edge to be brought into contact with a convex surface contacted by the two points. A tip 10 protrudes from and is moveably mounted relative to the straight edge or surface for measuring the profile of a surface contacted by the straight edge.

Abstract: A measuring instrument, such as a coating thickness measuring instrument, comprises a reader (6) arranged to read information provided on a calibration piece article (7), such as a calibration foil. The reader (6) can be an RFID reader and the information provided in a RFID tag. The information may be used to calibrate the instrument when the instrument is used to measure a property of the calibration piece. The reader (6) may also be used to read information provided on an article to be measured, to identify the article or a location on the article, or on a detachable probe of the instrument.

Abstract: A coating thickness measuring instrument has a probe for measuring the thickness of a coating applied to a substrate and producing an output relating to the measured thickness; a memory storing calibration data; and a processor arranged to process the output produced by the probe, together with calibration data stored by the memory, and produce a coating thickness measurement. The memory stores at least two sets of calibration data, each set associated with a different surface profile value and a user may select the set of calibration data to be used by the processor according to the surface profile of the substrate on which a measurement is to be made. This enables a user to make coating thickness measurements on substrates with at least two different, known, surface profiles without having to calibrate the instrument specifically for those surfaces.

Abstract: A surface profile measurement probe comprising two spaced apart points 20 for contacting a convex surface to be measured and a straight edge or surface 22 moveable relative to the two points to enable the straight edge to be brought into contact with a convex surface contacted by the two points. A tip 10 protrudes from and is moveably mounted relative to the straight edge or surface for measuring the profile of a surface contacted by the straight edge.