Multi-blow Impact Tests with high reproducibility

The MULTI GRIT TESTER 508 VDA is a stone hammer blow testing instrument that at first was
developed in co-operation with the “Verband der Automobilindustrie (VDA)” (Association of the
Automotive Industry) but now also meets the specifications of national and international standards.
The MULTI GRIT TESTER 508 VDA is used to assess the ability of single and multiple layers of
paints and similar coating materials to stand up to the impacts caused by small bodies of low mass
hitting the specimen at high speed as experienced on road and rail vehicles and other equipment
used in the transport field.

The MULTI GRIT TESTER 508 SAE features, like the VDA version, a good repeatability and
reproducibility of the test results. The bombardment of the test panels is carried out with determinate
grit (according to ASTM D 3170) which is accelerated by compressed air. Dependent of the
specifications of further standards (mostly of car manufacturers) other shot materials can be used, too.
The shot is entered automatically using an adjustable vibratory feed.
On a multifunctional display the working pressure, the duration of the test, the setting of the
vibratory feed and the number of tests conducted (total / temporary) can be read off alternatively.
An air accumulator in the system eliminates effects of momentary pressure variations in the external
compressed air supply.
The specimen fixing device of the MULTI GRIT TESTER 508 SAE is provided with an adjustable
impact angle. The adjusting unit for the impact angle allows to adjust the orientation of the test panel
relative to the direction of impact in the range from 30° to 90° in steps of 15°.
Contrary to the VDA version, the test panel in the MULTI GRIT TESTER 508 SAE is located completely
within the testing room during the whole bombardment procedure.
Due to numerous technical differences between both versions (conditional on the standards), a test in
accordance with VDA using the SAE version, is not intended and thus technically excluded.

Standards:

• DIN EN ISO 20567-1
• FORD FLTM BI 157-06
• RENAULT D24 1702
• PSA D24 1312
• SAE J 400
• ASTM D 3170