A precise, versatile and compact solution for coating thickness measurement

A precise, versatile and compact solution for coating thickness measurement

Keywords: Coatings, Measurement, Colour

The “eXacto” coating thickness gauge –manufactured by ElektroPhysik and available exclusively in the UK from Sheen Instruments Ltd, Kingston, Surrey – provides an easy-to-use and precise method of measuring the thickness of coatings on ferrous or non-ferrous substrates, in situ or in the laboratory. (Plates 1 and 2)

Compact and lightweight (only 200 g), the eXacto gauge claims a user-friendly menu for easy access of single value statistics, including the number of readings, mean value, standard deviation, and minimum/maximum values, or block value statistics, including the number of readings per block, mean value and standard deviation per block. The data memory can store up to 90 single readings or 45 block values.

 Plate 1 The eXacto coating thickness gauge

 Plate 2 The ‘Color-Guide Plus’

For quality assessment, a “limit value” is available for monitoring user-selectable tolerances, plus an alarm signal to indicate when set tolerances are exceeded.

The gauge operates by means of an integral “smart”magnetic-induction or eddy-current probe, which detects automatically whether the substrate metal is ferrous or non-ferrous, and is available in three variants: type “F” (magnetic induction probe) for measurements on steel, type “N” (eddy- current probe), and type “FN”,which has a dual function probe.

Measurement range of the “F” model is 0-3000µm (120 mils) and for the “N” and “FN” models is 0-2000 µm (80 mils). Accuracy of all models is ±27 pm + 3 per cent of reading (±0.08 mils + 3 per cent of reading).

An additional feature of the eXacto gauge is a special housing to store calibration standards so that calibration foils or a zero plate are quickly available to verify gauge accuracy.

Also new from Sheen is a colour measurement instrument– the “Color-Guide Plus” is said to enable precise colour matching to be carded out electronically in less than a second.

According to Sheen, the Color-Guide Plus will zero in on the five closest colour matches from a memory of 5,000 pre-loaded RAL or NCS colours or from a specific customer colour inventory, thereby avoiding the less reliable use of the naked eye and a colour chart, and saving time.

The lightweight instrument claims to provide up to 10,000 readings on one battery set and requires calibration only every 3 months. It is stated to be temperature-stable and can be used in any environment. The instrument is sold with a 3 year warranty on the main operating parts and a 10 year warranty on the illumination system.

The Color-Guide Plus also claims the bonus of acting as a complete colour quality control instrument, featuring all commonly used colour scales and illuminants, metamerism and a printout capability. The instrument only displays the information needed for a given application, from simple“pass/fail” checks to complex colour analysis.

Sheen Instruments also supplies the “Color-Guide Gloss” portable spectrophotometer, which simultaneously measures colour and 60° gloss, in compliance with ISO, DIN and ASTM specifications, to provide a complete analysis of colour “appearance”.

Further details are available from Sheen Instruments Ltd. Tel: +44 (0) 20 8541 4333; Fax: +44 (0) 20 8549 3374; E-mail: info@sheeninstruments.com; Web site: www.sheeninstruments.com