The Barcol hardness test is generally used on soft materials such as rigid plastics. It measures hardness based on indentation of a sharp point with a flat tip. The test is performed using a similar method and indentation device as that used to measure Shore D hardness however the Shore D indenter has a round tip. Barcol hardness is not a valid hardness measure for curved surfaces.
When pressure is applied to the device, a point penetrates the material and the degree of hardness is displayed on a dial, which is graduated from 0 to 100.
Portable
The Impressor is a convenient tool for testing the hardness of aluminum, aluminum alloys, copper, brass and other materials including plastics and fiberglass. The instrument is designed for use on fabricated parts and assemblies as well as on raw stock.
Easy to Use
No experience required; can be used in any position and in any space that will allow for the operator’s hand. The hardness reading is instantly indicated on the dial, which is divided into one hundred graduations. No waiting, preloading or separate measurements.
Lightweight
The Impressor weighs only 1 lb. 2 oz. The entire Impressor package comes complete with carrying case, adjusting wrench and two spare indenter points. The Impressor + case = 2 lb. 8oz. Shipping weights = 4 pounds, box = 12 x 11 x 6 inches, dimensional weight 5 pounds. (1.8 kilograms, box = 21 x 28 x 16 cm, dimension weight 2.5 Kilograms)
Official Barcol impressor scale, for testing of:
- Aluminum Alloys
- Soft Metals
- Plastics
- Fiberglass Sheet, Tanks, Surfaces
- Fire Department Ladders
- Composite Materials
- Rubber or Leather
- Laminates
- Lead
The Impressor is best suited for testing homogeneous materials. Materials of granular, fibrous or coarse structure will produce a wide variation in hardness readings because of the small diameter of the indenter point.
For accurate readings, material should be at least 1 /32″thick and large enough for a minimum distance of 1/8″ in any direction from the indenter point to the edge of the specimen. The testing area should be smooth and free from mechanical damage.
Simply exert alight pressure against the instrument to drive the spring-loaded indenter point into the material. The indenter point must be perpendicular to the surface being tested. On very soft metals, the highest reading should be used since cold flow permits the spring loaded indenter point to continue penetration.
Note: Physical characteristics of very soft materials are such that uniform correlation between different hardness measuring systems cannot be established. We recommend that Impressor hardness limits for each material be established by test.
