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Why a whip cracks
By
Mistress Michelle Peters
When one throws a whip a wave of energy is sent down the
thong. Energy is conserved (minus frictional losses) and
since energy = ½ mass times the square of the velocity it
follows that as the sectional mass of the thong decreases,
due to the taper in the whip, the velocity will increase.
When a whip cracks it's because the difference in sectional
mass between the butt and the tip accelerates the tip beyond
the speed of sound producing a sonic boom. A decent whip can
generate speeds in excess of 1400 feet per second. That's in
the same league as a .357 magnum.
Speed of action
Much of a whip's handling is dictated by the rate at which
weight is swapped for speed. A whip which retains much of its
weight further down the thong will be quite slow in the first
part of the throw but will pick up speed later. The advantage
of this is that less energy is lost in air resistance which is
proportional to the square of the whip's speed. A faster action
whip will have a more pronounced taper near the handle and will
lay out better in the air than a slower whip. Whips used for
multiple cracking and accuracy tend to have a fast action whereas
those with a slower action will tend to crack louder.
Naturally falling & lead weighted thongs
Most whip thongs are made entirely out of leather so will
have a fairly uniform density. In order to increase the
difference in mass between the butt and the point without
adding to the bulk lead weighting or shot loading may be
employed (there are a variety of techniques for this). The
result is a harder hitting whip or one of equal efficacy but
reduced diameter. The downside is that the step in density
between the weighted and unweighted sections, however slight,
will cause a small upset to the handling. Target and trick
cracking whips tend to be naturally falling while short or
narrow whips like signal whips have lead in their construction.
Number of strands in the strands in the plaiting
In general and up to a practical point a finer plaited overlay
is better than a coarse one. The stresses in a fine plait whip
are more evenly spread and the whip retains its firmness better.
Combined with the ability to plait narrow strands tighter this
makes for more efficiency as less energy is lost in damping and
friction. However, wider strands in a coarse plait will resist
impact better so whips for stunt and stockyard use tend to have
up to 12 strands in the overlay dropping to 6 at the point,
compared to trick whips which are generally 16 stranders with
8 at the point.
Construction
The plaited belly construction is the best technique by far for
making bullwhips, stock whips and blacksnakes. Here the whip is
built up in layers starting with a small core. Around this is a
plaited layer (commonly 4 strands, but I prefer 8 dropping to 6
in bullwhips and blacksnakes) which may, depending on the weight
and type of whip, then be encircled by a bolster of thin leather.
The overlay is plaited over this giving, in effect, a whip within
a whip. Since plaiting adds two layers of leather the central
core is tightly surrounded by up to 5 layers, resulting in a
dense, compact and efficient whip which will retain its integrity
over many years of use.
Fall and cracker
The end of a whip takes a lot of stress yet must be quite narrow.
In order to minimize damage and facilitate maintenance the last
couple of feet or so consist of a single tapering strand of heavy
duty cow hide hitched to the end of the plaiting. This "fall"
is more resistant to impact damage than the plaiting and when it wears
out it can be replaced without having to re-plait the point of the
whip. The cracker is the piece of (usually) twisted twine attached
to the fall. It is this bit which breaks the sound barrier producing
the crack. Crackers can wear out quite quickly or may come off the end
of the fall so it's a good idea to carry a couple of spares. I now use
longer, plaited crackers on my whips which last very well and sound
fantastic. Highly recommended.
Materials
Kangaroo hide is the finest whip making leather, being very much
stronger than the same thickness of cowhide. The density of its
structure gives clean edges to the strands which may be cut much
narrower than cowhide strands while still retaining the strength
of the leather. The natural color of greased 'roo hide is Saddle
Tan. Whips in this leather will, with use and exposure to sunlight,
darken to a lovely rich nutty shade of brown. Also available in
Whiskey (dark brown) and Brandy which is a very dark brown,
bordering on black. The leather I use is specifically prepared
for whip making, being bark tanned, bark dyed and drum stuffed.
I have tried other colors but they were not bark dyes and the
handling seemed to be inferior.
Care and Maintenance
A well made whip with a tight braid will be rather stiff when
new and will need to be gradually broken in. Resist the
temptation to speed up the process by applying neatsfoot
oil or similar to the thong or by forcing it unduly - these
practices will stretch the leather too harshly shortening the
life of the whip. If your whip has a cracker examine it to see
how it is attached - it will occasionally need replacing. Cracking
such a whip without one will quickly wear down the fall and won't
give as loud a crack. When practicing with a long whip, e.g. a bullwhip,
avoid hitting hard objects like walls and stony ground and don't drag
it about on gravel. Give the thong a light coating of hard leather
dressing e.g. Sedgwick's, every few months but keep the fall greasy
at all times.
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