What is the use of a durometer?
On the printing of skate wheels you can often see a number followed by an A. You get this measurement with a very specific tool: a durometer...
Par alfathor
Definition
A durometer is a small tool that measures the hardness of a surface. Obviously, hardnesses considerably vary according to the tested materials (metal, clothing, polyurethane of a skate wheel). It is why there are different measurement ranges.
The hardness measurement ranges:
• Rockwell B,
• Rockwell C,
• Vickers HV,
• Brinell HB,
• Shore (A ou D),
• HS,
• Leeb HL
• in hardness units DIN ISO.
There would be a dozen different ranges! In skating, you need a durometer in shores (A).
Shores A and D
The shore range measures the hardness of elastomers, of some plastic materials, of leathers and woods. Shore hardnesses stretch from 0 (softer) to 100 (harder).
– Shore A (for soft materials)
– Shore D (for hard materials)
How does that work?
You just need to press the ‘needle’ of the durometer on the polyurethane surface of the wheel. The depth of drive of a penetrator determines the hardness. The deeper it goes, the softer the material — and conversely.
Our tip
If ever you buy a durometer to test your wheels, be aware that you really have to press very hard to get as close as possible to the exact measurement. Normally, the measurement is done on a flat surface. Moreover, a difference of 2 shores A is tolerated for skate wheels…
Useful links
Anatomy of an inline skate wheel
Translation: Chloe Seyres
Photo : all rights reserved
