We received the following question from a customer named Lilly in Ohio:
“What is the difference between the Wyzenbeek method of abrasion testing and the Martindale? I often see both results listed on different fabrics but don’t understand what each of them mean.”
These two methods of testing the durability of fabric for upholstery use are actually very different but both of them are commonly used. Let’s begin with the actual definition of abrasion. Abrasion resistance is “the ability of a fabric to resist surface wear caused by flat rubbing contact with another fabric.”
The Wyzenbeek method is a standard test used in the United States. It is often referred to as the “rub test” as people often ask how many “double rubs” a particular pattern passes. The Wyzenbeek machine tests the fabric in both the warp direction (up and down) and the fill or weft direction (right to left). A sample of the fabric is cut into two pieces and each are pulled tight in a frame where it is held stationary. A piece of cotton duck fabric is used as the abradant and is rubbed back and forth over the fabric, known as the “double rub.” The samples are checked after every 5,000 double rubs and if the fabric is still holding up, it goes through another cycle of 5,000 and so on. When wearing has become evident or two yarn breaks have occurred, the end point has been reached, and the fabric is rated by the last check point it passed. So in simple terms, this means if there isn’t any noticeable wear at the first check of 5,000 rubs but it shows noticeable wear at the next cycle it must be rated as only 5,000 double rubs. Most of the time, 15,000 double rubs is considered suitable for heavy use in a residential application.
The Martindale test method is usually performed on imported product, and uses a different method when rubbing the fabric. The sample is mounted flat and a piece of worsted wool cloth is used as the abradant. It is rubbed in an elliptical shape. Again the method is checked in 5,000 cycles and when two breaks occur or there is a sufficient change in shade or appearance, the fabric is rated by the last checkpoint it passed. A rating of 20,000 rubs is considered suitable for heavy duty residential use.
There is, however, one misconception about the two methods. There is no correlation between the two methods; you can not estimate the number of cycles on one test if you only know the test results from the other method.
I hope I was able to explain this in simple terms without getting into too much detail. Lilly, thank you for this question, it was a good one that I am sure many of our readers will find helpful.
Alice Guercio, Vice President of Product Coordination and a Kravet veteran for more than 15 years, travels the world to source and develop new product for Kravet. She is one of our top experts on textiles. If you have a question about fabric for Alice, email her at firstname.lastname@example.org and your question may become the subject of a future article.
*Fabric pictured above is Candice Olson for Kravet.