Both the bellies and the overlay are made of selected veg tanned kangaroo.
The bull whips start with an 8mm steel rod handle and a Kangaroo
core. Over that is a 4 plait belly, a kip bolster, then a 6 plait belly,
another bolster and the final overlay in either 12 or 16 plait. During
the construction phase, there is a lot of plaiting soap applied to each
layer of leather. This "soap" is a combination of actual soap and fats (grease) that will protect and extend the life of the leather in the whip to keep it from drying out over the years. See the anatomy of one of my 8ft bullwhips here.
Why Kanagroo? - The end of the thong on a whip takes a lot of punishment and needs to be strong to stand up to the demands placed on it. Kanagroo leather is the strongest leather in the world. Studies conducted by the Australian Commonwealth Scientific and Industrial Research Organization (CSIRO) confirm that kangaroo is one of the strongest leathers of similar substance available.
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.
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. 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 point 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.
The Australian kangaroo industry produces a range of meat and leather products from animals harvested from the wild under strict government controlled Management Plans. These ensure the harvest is sustainable and humane. A wide cross section of Australian ecologists support the kangaroo industry as being both sustainable and environmentally wise. Many argue kangaroos, which are native to Australia, are a more environmentally friendly livestock option than introduced sheep and cattle.
The picture below is a cross section of one of my whips showing the different layers of leather.
Things to watch out for when buying a whip:
The belly material should be leather. A lot of cheap whips use material other than leather for the belly. This can be anything from rope to as bad as twisted paper. These materials don't add enough weight to the thong. I have seen both before. In fact, below is a picture of a whip I bought before I knew better. It was much too expensive for what it was. The overlay leather was really not that bad looking, but it was very difficult to crack and took too much effort.
The thong should be firm when squeezed between your fingers. If the whip feels mushy, that is a very good indication of a poorly made whip. Either the belly material is bad, or the whip was not plaited tightly, or a combination of both.
Taper is also very important. A well made whip will taper gracefully all along the thong down to the point. A whip with a rope core will many times taper down to the diameter of the rope and then stay that diameter to the end.
Construction
Besides an all leather belly, another part of the construction process that is very important is binding each layer of leather in front of and following the transition point of the handle. This binding is what keeps the whip from breaking down with use and becoming like a wet noodle or rope. It is an essential part of the whipmaking process and can not be short changed. My whips are bound starting with the core and ending with the last bolster. Every layer is bound tighter and heavier than the last.
