Home Site Map Contact Us Search Our Site
Home > Products > Hardness > Pencil Scratch Hardness Tester
Pencil Scratch Hardness Tester

Gardco/Wolff Wilborn

ISO 15184, ASTM D3363, JIS K-5600, ECCA-T4-1, BS 3900-E19, SNV 37113, SIS 184187, NEN 5350, MIL C 27 227

Gardco/Wilborn Pencil Scratch Tester

The Gardco/Wolff Wilborn Pencil Test offers 2 choices of either mechanical pencil or certified UNI pencils. The scratch hardness test determines the resistance of coatings to scratch effects on the surface.

This test is of particular value for furniture or vehicle lacquers, but it is also a useful aid in the development of synthetic resins or other film forming substances.


Test Principle

The Wolff/Wilborn pencil test uses constant pressure and variable hardness of the graphite lead as its fundamental principle. Pencils of varying hardness, starting with the hardest lead, are moved over the surface under a fixed pressure of 7.5 Newtons (765g±2%) and at a fixed angle of 45 degrees to the surface.

The degree of hardness of the pencil which damages the surface is taken as a measurement for scratch hardness. Under ASTM, fourteen pencil leads in the range from 6B to 6H are used. (7H, 8H, and 9H are sold separately.) The pencil leads can be exchanged quickly and easily. The test method is fully described in ASTM D 3363-92a and ECCA T4 (1984). The instrument comes complete with mechanical pencil, 14-piece lead set, abrasive paper and carrying case.


Instructions For Use
The test surface needs to be correctly prepared in accordance with the specification being used. In all cases, it must be flat and smooth. The test should be performed at 73°F ±4°F (23°C ±2°C) with a relative humidity of 50 ±5% (ECCA;T4) or 73.5°F ±3.5°F (23°C ±2°C) and 50 ±5% relative humidity (ASTM D 3363). A 6 x 1” abrasion strip of 400 grit sandpaper is provided for fine dressing in compliance with ASTM D 3363.
  1. Select a mid range lead or wooden pencil.
  2. Place lead in holder. In the case of wood pencils, remove approximately 3/16 to 1/4" (5 to 6mm) of wood from the pencil using a pencil sharpener. Load the pencil in the upright alignment tool. Using the pencil alignment tool 90° to the abrasive paper, rotate until a flat, smooth and circular cross section is obtained, free of chips or nicks on the edge of the cross section.
  3. To set the proper pencil depth, stand the Hardness tester upright. Insert the dressed pencil until it rests on the substrate. Tighten the knurled set screw to secure pencil in position.
     
     
  4. Place the HA-3401 on the test surface and push it forward approximately 1/4 - 1/2" (6 - 12mm). Be sure to hold the gauge by the wheel hubs.
  5. Rotate the pencil 90° and move the gauge 1/2" (12mm) to one side of the first test. Repeat Step 4.
  6. Examine the coating for indentation or scratching. If there is none, repeat the test using a harder pencil. If the surface is scratched or indented repeat with a softer pencil.
  7. Repeat step until a pair of pencils is found, one of which scratches/indents the coating, the other does not.

Available Items - Literature
Prices subject to change    Prices listed in US dollars for domestic shipments within US, Canada, & Mexico only    Export orders require quotations - click here for a quote     For more info call us 1-800-762-2478 or 954-946-9454.
Item Number Item Prices
HA-3401 GARDCO/Wolff Wilborn Pencil Scratch Hardness Tester Kit, with mechanical pencil & lead set $388.00
HA-3403 GARDCO/Wolff Wilborn Pencil Scratch Hardness Tester Kit, with Certified JPIA 17-pencil set 495.00
HA-3411 Mechanical Pencil Lead Holder, replacement 21.00
HA-3414 Turquoise Lead Set, replacement (14 leads 6B-6H ) 36.00
HA-3363/XX Individual leads available in sets of 12 (6B-6H) 20.00
7H, 8H, & 9H sold individually with limited availability (HA-H501/07/08/09) P.O.R
HA-3417 Sandpaper Paddle, replacement 3.50
HA-3460 Certified Mitsubishi UNI/JPIA set of 17 pencils 6B-9H 161.50
HA-3468 Pencil Sharpener (point and flat) 12.50
HA-3419 Pencil Lead Dressing Tool, replacement 8.00
Home    Hardness    How To Order    Top Of Page Paul N. Gardner Company, Inc. • 1.800.762.2478 • Fax 954.946.9309