Many surface coatings are subject to the risk of damage by impact. Impact testers allow reproducible conditions of impact to be defined. The 807 allows pass/fail limits to be established and a classification of the coating to be achieved.

This instrument consists of a graduated vertical tube mounted into a solid base. This tube acts as a guide for an impacting weight of pre-determined mass. The height from which this falls is variable. By using the locking collar, exactly the same force of impact can be produced for each test. The weight and indenter are combined and strike the panel directly.

The test panel is placed on the die. The panel is held firmly by a clamping sleeve. The weight is raised to a set height and released. The height is increased by 1 in. (2.5cm) intervals until coating failure is seen. The 807 can be used as a pass/fail test by calculation of the impact energy (height x mass), and for the classification of the test sample. For detailed procedures, please refer to the relevant national standard.

• Indenter and die diameters have been revised
  
• The weight has been changed
  
• The clamping method improved
  
• The maximum impact height increased
  
• New adjustable indentation depth