ABOUT WYZENBEEK DOUBLE RUBS AND CYCLES AND
MARTINDALE MOVEMENTS, CYCLES, RUBS AND LISSAJOUS FIGURES
The Wyzenbeek Abrasion Tester is a type of abrasion testing instrument.
The Wyzenbeek instrument first came into use around the early 1920s
in the United States. It uses an oscillating cylinder covered with
abradant to rub against the specimen being tested, which is held
stationary against the abradant under pressure and tension.
The Martindale Abrasion Tester was developed by J.G. Martindale
in the early 1940s under the auspices of the Wool Industries
Research Association in England. It uses an oscillating top
plate to move a circular test specimen in a grouping of elliptical
repeating paths over a stationary abradant under pressure.
There are a set of 16 sequentially changing ovals or back and forth ellipses
executed in each repeating group. The precise repeating group is known as a
Lissajous figure.
Quantifying The Abrasion Resistance Of Textiles can be performed in several
ways each of which requires the rubbing of the fabric of interest against a
standard abradant and the assessment of how much abrasion it takes to either
create a hole, aesthetic deterioration, strength loss or mass loss.
Upholstery testing product performance specifications use the amount of
abrasion required to create a two yarn break hole in the fabric of interest
as the quantitative
operational definition of abrasion resistance. The amount of abrasion is
measured by the counter on the abrasion testing instrument.
For the Wyzenbeek, each time the cylinder moves forward and backward the counter
on the front of the instrument is incremented by 1. This cyclical movement is
typically referred to as a cycle or double rub and is defined this way in the
current ASTM D4157 Test Method. The video below shows the Wyzenbeek in action
with the abrasion count as it would be used in a Contract Upholstery or similar
product performance specification:
Traditionally on the Martindale instrument every time an elliptical back and
forth path is completed the counter on the front of the instrument is
incremented by 1. This single elliptical or oval back and forth path is commonly
referred to as a rub in Europe or in common parlance as a cycle in the United States.
It is currently defined in ASTM D4966 as a movement but the term movement is almost
never used in reporting Martindale abrasion test results or in product performance
specifications referencing Martindale abrasion.
ISO 12947-1:1998(E) refers to ASTM movements as rubs. Abrasion cycles are
technically defined in both ISO 12947 and ASTM D4966 as the 16 movements or rubs
making up the Lissajous repeat however it should be kept in mind that the use of
cycle in this manner is not commonly used in industry. U.S. product performance
specifications and test reports use the word cycles as being synonymous with ASTM
movements or ISO rubs.
The video below shows the Martindale in action performing ASTM D4966 with the
abrasion count in cycles as it would be used in a U.S. contract upholstery or similar product
performance specifications shown in blue on the top row of text. Rubs, ISO Cycles,
ASTM Abrasion Cycles, and Lissajous Cycles are also shown.