Thread: Ranking of strop materials

Originally Posted by mainaman

I thought that shell cordovan is probably the finest leather you can get on a strop?
For me cotton webbing is the best, nylon is ok but nothing special.

Here's an explanation of the properties of Kangaroo Leather. Take from it what you will!

Studies conducted by the Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) confirm that kangaroo is one of the strongest leathers of similar substance available.[5][9]

Similarly when split into thinner substances kangaroo retains considerably more of the original tensile strength of the unsplit leather than does calf. When split to 20% of original thickness kangaroo retains between 30 to 60% of the tensile strength of the unsplit hide. Calf on the other hand split to 20% of original thickness retains only 1-4% of original strength.[9]

Kangaroo leather is lighter and stronger than the hide of a cow or goat. It has 10 times the tensile strength of cowhide and is 50% stronger than goatskin.[10]

Studies of the morphology of kangaroo leather help explain its particular properties.

The collagen fibre bundles in cattle hide are arranged in a complex weaving pattern. The fibres are often at angles as much as 90 degrees to the skin surface. Cattle hide also contain sweat glands, erector pili muscles and a distinct gradation in elastin levels, concentrated in the upper part of the skin. Kangaroo on the other hand has been shown to have a highly uniform orientation of fibre bundles in parallel with the skin surface. It does not contain sweat glands or erector pili muscles and elastin is evenly distributed throughout the skin thickness [11]. This structural uniformity explains both the greater tensile strength of the whole leather and the greater retention of strength in splits. Bovine skin is much more complex in cross section. Hence in whole section it has many more weak points from which tears can start when placed under tension. In addition when sliced into splits the collagen fibres running at significant angles to the skin surface will be cut. These then become weak points in the structural strength.