Product Description
Technical Specification
Instruction ManualData Sheet

Elcometer 501 Pencil Hardness Tester

The pencil hardness test, also referred to as the Wolff-Wilborn test, uses the varying hardness values of graphite pencils to evaluate a coating’s hardness.

The Elcometer 501 Pencil Hardness Tester has been designed to ensure that the cylindrical pencil lead is maintained at a constant angle of 45° and exerts a force of 7.5N (1.68lbF).

The pencil lead, prepared beforehand using the special sharpener and abrasive paper, is inserted into the Elcometer 501 hardness tester and pushed over the smooth, flat coated surface.

The lowest hardness value of the pencil which marks the coating determines the coating’s hardness rating.

501 pencil test
Elcometer 501 Pencil Hardness Tester

Technical Specification

Part Number Description Certificate 
H501----1 Elcometer 501 Pencil Hardness Tester ο
Dimensions (with Pencils) 130 x 130 x 50mm (5 x 5 x 2”)  
Weight 2.1kg (4lb)  
Packing List Elcometer 501 Pencil Hardness Tester, pencil set (14 pencils, grades 6B - 6H), positioning block, x2 pencil sharpener, abrasive paper block, carry case and operating instructions 

ASTM D 3363, BS 3900-E19, ECCA T4, EN 13523-4, ISO 15184, JIS K 5600-5-4

Standards in grey have been superseded but are still recognised in some industries.

ο Optional Calibration Certificate available


T99923040-1 Pencil Sharpener (6H to 2B)
T99923040-2 Pencil Sharpener (3B to 6B)
T99923039 Set of 14 Pencils (6B to 6H)
T99923042-1 12 Hardness Pencils (6B)
T99923042-2 12 Hardness Pencils (5B)
T99923042-3 12 Hardness Pencils (4B)
T99923042-4 12 Hardness Pencils (3B)
T99923042-5 12 Hardness Pencils (2B)
T99923042-6 12 Hardness Pencils (B)
T99923042-7 12 Hardness Pencils (HB)
T99923042-8 12 Hardness Pencils (F)
T99923042-9 12 Hardness Pencils (H)
T99923042-10 12 Hardness Pencils (2H)
T99923042-11 12 Hardness Pencils (3H)
T99923042-12 12 Hardness Pencils (4H)
T99923042-13 12 Hardness Pencils (5H)
T99923042-14 12 Hardness Pencils (6H)


Hardness Tester

How to measure coating hardness using the Wolff Wilborn Pencil Hardness Test

One of the most common methods of determining coating hardness is the pencil hardness test, also known as the Wolff-Wilborn method, where a pencil of a known hardness is pushed across the coating at a specified angle, under a constant force.

Click here to download the video script in English.