|Complies with BS 3900;E2, DIN EN ISO 1518.
Coating performance is related to many factors that include the hardness of the coating with other physical properties such as adhesion, lubricity, resilience etc., as well as the influence of coating thickness and curing conditions.
It is a quantifiable indication of the extent to which serious damage is resisted when a loaded needle is raked across a relatively smooth, flat surface.
The scratch tester is designed to meet the scratch test requirements described in method of Test for Paints BS 3900 Part E2 / ISO 1518 1992, BS 6497 (when used with 4kg), and may be adapted to suit other specifications such as ASTM D 5178 1991 Mar resistance of Organic Coatings and ECCA- T11 (1985) Metal Marking Resistance Test.
The Scratch Tester operates in 220V 50HZ AC supply. It is encased with a cover enclosing the gears and other parts for operating the slide at a constant speed (3-4 cm per second) and an arm lifting mechanism. The needle arm is counterpoised and rigid to prevent whip or chatter at the ball-point.
A 1mm tungsten carbide ball ended needle (normally supplied with each instrument) is held in a check at 90º to the test panel and can be easily removed for inspection and replacement. The needle will provide, with care, a long useful life without the need to replace the tip after each test.
Weights providing increments of 50gms to 2.5kgs mass are loaded above the ball ended needle, additional weights up to maximum 10kg loading are available as optional accessories for harder coatings.
Standard test panels (usually metallic) of 150 x 70mm with thickness up to 1mm can be used
Method of test
Reference should be made to the relative test procedure, in general as follows:
Check suitable needle is fitted
Clamp test panel to slide
Load needle arm with weights to determine threshold of failure,progressively increasing load until failure occurs.
Actuate slide,If failure occurs, needle on voltmeter will flick over. Only conductive metallic panels will be suitable for this test result
Remove panel for visual assessment of scratch.
ECCA Metal Marking Resistance test is a procedure designed to evaluate the resistance to a smooth organic coating when rubbed by a metallic object.
Comes complete with:
Automatic Scratch Tester