Abstract: A control system for controlling abrasive blasting apparatus and an abrasive blasting apparatus including such a control system. The control system controls delivery of air and blast media to a blast nozzle of the abrasive blasting apparatus. The control system includes a deadman's switch, the deadman's switch features a user operable control. The user operable control is moveable from a first position, where the control system causes the abrasive blasting apparatus to not deliver air or blast media, to a second position where the control system causes the abrasive blasting apparatus to deliver both air and blast media. When the user operable control is in an intermediate position between the first and second positions, the control system causes the abrasive blasting apparatus to deliver air but not blast media. The control system may have control elements whose state may be sequentially changed by the user operable control as it moves.

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.