A
splitting maul (or
mall) is a
heavy, long-handled
hammer used for splitting
a piece of
wood along its grain. One side of it
is like a
sledgehammer, and the other
side is like an
axe. In some countries it is
also called a block buster.
Wood splitting tools
Wedged mauls
A typical maul for wood splitting will have a head weighing in
region of 4 kg (8 lbs). Traditionally, mauls have a
wedge-shaped head, but some modern versions
have
conical heads or swiveling
sub-wedges.
The original maul resembles an
axe but with a
broader head. For splitting wood, this tool is much better than a
typical axe. The weight of it is more advantageous and due to its
width, it is less likely to become stuck in the wood. The wedge
section of a maul head must be slightly convex to avoid jamming and
it cannot have the elongated "hollow ground" concave-section that a
cutting axe may use.
Unlike an axe, maul handles are normally straight and closer to
round than the elongated oval axe handles tend to be. A maul's
handle, unlike an axe, is intentionally used for levering as well
as swinging. The handles are typically made from hickory, though
synthetic fibreglass handles have become common. Plastic handles
are more difficult to break and their factory-attached heads are
less likely to work free with the levering action of a maul. In the
early 1970s a triangular head design with an unbreakable metal
handle was introduced called the "Monster Maul."
Separate wedges
Splitting may also be done with a separate wedge and a large
hammer. As this allows several wedges to be used together, it
permits larger logs to be split.
To avoid mushrooming the head of the wedge, they are driven with a
heavy wooden mallet rather than an iron hammer. In parts of England
the word "maul" denotes this tool with a very heavy wooden head.
It is also
known as a beetle; there is a well known pub on the River Thames at Moulsford
called the Beetle and Wedge
.
Powered log splitters
Hydraulic log splitters are
commonly used today. They can be either horizontal or vertical as
shown here.
Wood splitting techniques

Monster Maul
The maul is most commonly struck onto a flush-cut section of log,
usually standing on end atop a splitting stump or other suitable
base. Most cut sections can be split in a single downward chop of
the maul, splitting the wood apart along its grain. Mauls regularly
become stuck in the log for several reasons, such as the wood not
being struck with adequate force, the wood containing hidden knots,
or the length of wood being too long. Unlike an axe, mauls are
effective longer after the edge dulls, as the primary mechanism is
that of a wedge pushed through along the
wood
grain, and not a cross-grain chop of an axe. In some cases,
longer logs may be split while they rest length-wise on the base or
ground. Mauls often become stuck in logs mid-split requiring a
"full-lift" chop to be used. This involves the chopper reswinging
the maul, but this time lifting the half-split log while still
attached to the embedded maul, often requiring one or two
additional full-lift chops. Another technique for splitting upright
logs of thicker diameter is to land the maul's full force
off-center of the log, usually removing 1/4 of the mass of the log.
When repeated, large logs that would ordinarily cause the maul to
be embedded on a center-strike can be handled easily.
Safety considerations

Hydraulic splitting machine
The hammer side of the maul is often used in wood splitting when
combined with a splitting wedge, driving the wedge into the wood in
the same fashion as the maul itself. This is generally used when
attempting to split logs with a large diameter. Modern mauls are
made of a strong enough steel to withstand the metal-to-metal
contact without chipping. However, it is still common for the wedge
itself to chip off. This can be dangerous as flying chips of steel
could damage the eye. This is also the easiest way to break a
maul's handle because the wedge is a very small target as opposed
to the whole log, and can be overshot, resulting in the handle
hitting full-force onto the wedge. This greatly weakens the handle,
and can cause it to break after only a few over-shots.
Harder seasoned logs which have dried sufficiently often split
apart with enough force that each half tumbles away at some speed,
which is a hazard for people or objects nearby.
A common danger for inexperienced splitters is to miss the upright
log entirely or give it only a glancing blow. If the maul lands
beyond the log, the maul handle may either bounce or break. If the
maul lands in front of the log, it may hit the feet of the splitter
if they are in a closed stance. If the maul hits the side of the
log without biting in, the maul commonly will bounce to one side
and to the ground. In this situation, even a widened stance may
still leave the splitter's feet vulnerable.
When performing the "full-lift" chop described above, the splitter
must never raise the maul and log above his head.
Generally speaking, a maul should never swing to the side. Rather
it should be powered through the drop, using force to assist the
natural weight of the maul. In addition a suitable splitting base
is one of the most important components to splitting wood with a
maul. Wood can be split directly off the ground, although this is a
disadvantage for a few reasons. For one the ground, if not frozen,
will give on each blow, thereby weakening the overall effect of the
blow. The second disadvantage is that it can present the log to be
split at a low level, forcing the person splitting the wood to bend
over during the swing, which causes back fatigue. The best bases
are a flush-cut segments of logs, usually about one foot tall, and
made of hard wood. For repeated season use the top open grain may
be treated slightly. The diameter should be at least 100 per cent
larger than that of the diameter of the wood placed atop it for
splitting, and the base should be placed on firm ground.
Another technique to improve safety involves pinning the head of
the maul to the handle. Repeated use can loosen the head, and if
the wedge or expander fails, the head will fly from the handle.
Placing a pin involves drilling a small diameter hole through the
side of the maul, into and through the handle, and usually out the
other side. A small, flush, or counter-sunk pin of aluminum or
similar material should be placed through the head and secured. It
is critical that the pin not protrude from the side of the maul
head.
See also