Senze-Instruments

Hardness Test Pencil, Model 318

For the Measuremen of the Hardness of Protective Coatings

The degree of hardness of paint films, plastic coatings, etc. can be accurately measured and recorded with the Hardness Test Pencil, Models 318 and 318 S, no matter whether on a level or curved surface, small or large.
The instrument is always ready for use and, because of it’s small size easy transportable, an asset which will be appreciated by all concerned with hardness tests.

The handling of the Hardness Test Pencil is extremely simple.
The estimated or known spring tension is set with the help of the slider. Holding the instrument upright and placing its point on the test surface one draws a 5 to 10 mm long line at a rate of approximately 10 mm/sec.
The stylus should produce a scratch which is just visible with the naked eye. If the spring pressure is too high, the scratch is clearly visible; if too low, no scratch appears. The applied pressure, fixed by locking the slider, is marked in Newtons

3 Pressure Ranges:

• 0 - 3 N (blue marked)
• 0 - 10 N (red marked)
• 0 - 20 N (yellow marked)

4 Test Geometries:

• 0.75 mm (Bosch)
• 1.0 mm (ISO)
• 0.5 mm (van Laar)
• 0.5 mm (Opel)

Hardness Test Pencil, Model 318 S with rolling head

For the Measurement of the Hardness of Protective Coatings


Technical Data:

Compression Springs: spring steel

Marking pins

• nos. 1, 2 and 3: tungsten carbide spheres
• no. 4 spring steel, with special tip geometry

Stylus point dia:

• no. 1 0.75 mm (Bosch)
• no. 2 1.0 mm (technically equivalent to ISO 1518)
• no. 3 0.5 mm (van Laar)
• no. 4 0.5 mm (Opel)

Total length: 160 mm

Diameter: 16 mm

Weight, net: approx. 250 g