It's generally easier and more exhilarating to tear something apart than to
build it up. Demolition is often the first step of a remodeling project, the
phase when you're bringing the worksite back to a blank canvas. With a
little elbow grease, a big sledge hammer and a crow bar, you can really do
some damage. Of course, there are some power tools and purpose-built
implements that help bridge the gap between hard work and smart work. Here's
a look at some new demo tools for your next foray into destruction. 

Ripping with Manpower

For a demolition job, the first category to consider is manual hand tools.
Although a sledge hammer can dismantle a brick wall, even a heavy framing
hammer can make some serious holes in masonry or wood, and do so with a more
measured and targeted strike. Both heavy sledges and large framers can be
used as basic demolition tools, as well as to drive ripping bars. 

A 5' breaker bar can help crush rock bed for post holes.  

Pry bars, crow bars, rippers, etc. provide the necessary leverage to pull
nails and rip up siding, decking, flooring or virtually any other material
you need to pry away from a structure. When selecting a demo bar, pay
attention to the bar's length (thus leverage), weight and quality of
construction. The bigger the bar, the more destructive power it will
brandish, but the big ones are usually heavier and can fatigue the user more
quickly.  

For example, we recently put to use a 5-foot breaker bar to demolish the
rock bed beneath the topsoil in a co-worker's yard. We were building a
fence, and the rock was so solid that it stalled the rented gas-powered
auger we were using to dig the post holes. The large, pointed bar worked
well at splitting the rock, but pistoning the heavy iron rod up and down
tired us quickly. If you've got lot rock-crushing in your future, then
consider forgoing the bar for a powered breaker hammer that you can find at
most rental yards. (More on that later). 

Shown is the Gutster demolition bar, now available in orange with a more
narrow handle. 

As far as recommended demolition bars,  we used the Gutster demolition bar
on a deck-board replacement job and loved it. The hollow handle cuts down on
the weight of the 48-inch bar while retaining excellent balance and lifting
power. The angled head with chiseled points can get into small crevices, and
the head features prongs spaced to straddle 2-by beams and joists. We used
the Gutster Series 2 but recently discovered the manufacturer offers a newly
upgraded model, available in two different lengths and with an even slimmer
handle.

Shown is the Dominator Ripping Chisel from Mayhew Tools

Another keeper comes from Mayhew Tools. The heavy-duty Dominator Ripping
Chisel is constructed of heavy-duty 3/4-inch steel. Great for removing floor
tile, wall paneling or plywood, or for use on any overhead demolition where
you need a medium-sized wrecker for easy maneuverability, but one that can
really handle tough ripping action. The business end features a two-prong
chisel with a couple of nail pullers, and the shaft goes all the way through
the handle to the end cap. The patented two-composite handle really shines
on this tool, because demo bars aren't usually this comfortable to hold. I
also like that the end of the handle is capped, which let's you strike the
bar with a hammer without damaging the handle.

Electrical Breakthrough

For a powered approach to demolition, we'll make our entry point with
electric rotary hammers. These tools have an electro-hammer system with a
free-floating percussion piston. The impact force of the tool is much
greater than that of a standard hammer drill. With rotary hammers, the tool
supplies all the impact without any additional pressure from the operator.
The impaction ramps up the breaking power while cutting down on user
fatigue. 

In fact, applying pressure can reduce the impact of the breaker. These tools
are an excellent choice for boring strategic holes in concrete or masonry to
weaken the structure. Rotary hammers are sold as dedicated units, but also
as combination tools that offer "rotary hammer" plus "hammer only" action-an
excellent feature for chiseling away tile and mortar. Rotary hammers provide
lots of breaking power in a portable package that can be used horizontally
or vertically. Most models are corded, but some are available as cordless
units with 36-volt lithium-ion batteries. They also vary greatly in size and
weight.

Shown is Hitachi's new DH45MR Rotary Hammer.

The chucks in modern rotary hammers are designed to accept special bits for
additional strength. The most common chuck systems were actually designed by
Bosch, dubbed the SDS-Plus and SDX-Max Systems. The breaker points, commonly
referred to as "tools" or "steel," usually range in size from 5/8 to 1-3/4
inch. 

Bosch Power Tools, which developed the SDS tool system for hammer drills,
features a full line of carbide bits, carbide cores, steel points and
chisels. 

The next step up in the size of destruction tools are dedicated portable
demolition hammers. Although rotary hammers provide drilling action,
demolition hammers provide only hammering action, designed specifically for
breaking up concrete, masonry and stone. Although not as versatile as rotary
hammers, the dedicated demolishers are better engineered to withstand the
heat and wear of breaking rock, day in and day out. Like rotary hammers,
portable demo hammers can be used for vertical or horizontal work. However,
these tools can cost more than $500, so if you only need it once, then it
would be wisest to rent. The same goes for any larger pieces of demolition
equipment you might need.

Shoown is Hilti's 905 AVR.

New Destroyers

Over the past two months tested a few new electric hammers on a couple of
different projects. These included the Hitachi DH45MR, Bosch 11316EVS, Hilti
TE 905 AVR, Metabo's Porsche P9711, as well as rental yard favorite, the
Bosch Brute. Here's what we thought:

Hitachi DH45MR

In the realm of rotary hammers, we tested Hitachi's new DH45MR. According to
Hitachi, the DH45MR offers the fastest drilling and chiseling speeds on the
market. Although our staff isn't privy to all the tool specs on the market,
we can say with confidence that it's a real beast of a rotary hammer. It
boasts a 1-3/4-inch SDS Max breaker capacity and a "best-in-class" impact
energy of 11.4 foot-pounds. The control dial offers two modes of operation:
hammer-drilling and hammer only. A 12-Position lock mechanism lets the user
select chisel position. Constant speed control delivers efficient
performance even under stressful loads. And, variable speed control gives
the DH45MR a full-load RPM from 120-240 and an impact rate of 1,200-2,500
BPM. 

The DH45MR also comes with Hitachi's patented IDI technology that enables
the aluminum housing to be integrated with an injection molded inner nylon
core. This technology combines the durability of a metal bodied tool with
the double insulation advantages of today's plastic housings. This allows
the tool bearing to sit in die-cast aluminum instead of plastic to extend
the life of the tool. A quick online check found a new DH45MR selling for
$568.  -MW

Hilti TE 905 AVR

Hilti's 905 breaker provided the serious performance we have come to expect
from Hilti's line of tools. The tool's design lends itself to vertical
applications where it excelled at chipping and breaking apart concrete
footings. Lighter than the larger Bosch Brute, the 905 sprinted through 

4 inches of concrete so effectively that it became the tool of choice when
we needed more power than the lighter units, but did not need the largest
tool in our test group. The 905 uses 1,600 watts of power, so don't skimp on
the extension cord or you will end up with a 75-foot light bulb filament.
Hilti's 905 uses AVR technology to reduce vibration and also incorporates a
soft-start feature that we found very helpful when driving Oz-Post pilings
and needed to cease pounding while we checked levels. The feature allowed us
not only to check levels without turning the switch off, but allowed us to
also drive in the posts at a very controllable speed. 

For concrete demolition to remove decking support posts, we used Hilti's
self-sharpening line of chisels and bits. We will be using the Hilti bits in
upcoming projects to get a better understanding of the self-sharpening
feature's effectiveness. With limited use the bits have performed well. 

Hilti offers a full line of bits for the 905 Series, ranging from roughing
bits, chisels and ground-rod installers, Hilti has the bits to meet the
demands of its professional customers. The DIY crowd will like the 905 if
they can rent it instead of the larger jackhammers, as its lighter weight is
much easier to work with. For simple demolition the 905 would be an
excellent choice. The Hilti sells for less than $1,500 online. -HJ

Bosch 11316 EVS & the Brute

In terms of power-to-weight ratio, the Bosch 11316 demolition hammer
outclassed the other units. While it may have lacked the power of the Hilti
905 or the behemoth Brute jackhammer, for all-around demolition the 11316 is
hard to beat. On horizontal applications the Bosch broke through brick and
concrete block walls with ease, whereas the two larger units, the Brute and
the Hilti 905 were too heavy for any extended horizontal use.

Bosch offers a complete line of bits and chisels for the 11316, and the unit
will accept SDS-Max bits of any make. The variable speed allows the user to
control the speed of the tool, allowing slower speed for tile-removal work
and other light demolition and higher speeds for tackling tough concrete
removal projects. 

Another use for the 11316 was the spade bit that made digging footings in
heavy clay soil a quick task. Usually this chore is back-breaking and
time-consuming, but both the Bosch and the Hilti spades saw a lot of use
during several deck-building projects. The biggest obstacle was keeping the
spade from burying itself too deep, too fast. The Bosch 11316 also has a
multitude of tasks it can perform not associated with demolition, such as
ground rod driving, (or rebar driving for landscape lumber), core drilling
and it was even used to drive galvanized posts into the ground.

For the professional, this tool is a winner for its flexibility. With a
weight of approximately 23 pounds, it is no lightweight, but compared to
comparable units this is a good choice if you expect to be using the drill
in horizontal fashion. A range of 4.4 to 18.4 foot-pounds per blow and a BPM
of up to 1,890 ensure versatility for a multitude of tasks. The online price
of the unit is a bargain at less than $800. For the advanced do-it-yourself
person, this tool's flexibility and lower costs make it a reasonable choice
if you have lots of demolition work ahead and want to work at your own pace
without regard to rental fees. -HJ

The Brute

The Bosch Brute is a huge commercial-grade jackhammer we borrowed from a
local rental yard. It's very heavy and very expensive and only makes sense
to own if demolition (or renting equipment) is your stock and trade.
However, if you've got an immovable object, the Brute will probably move it.
It's a cannon.

SIDE NOTE

Metabo Porsche P7911

In my younger days I dreamed of owning a Porsche 911. Well, finally I got my
hands on one. No, not the rear-wheel drive sports car that dominated auto
racing like no other make has. Instead, this is the Porche P7911
Multihammer, a joint project of Metabo Tools and Porsche Design. The outside
of the drill says Porsche Design, the inside says Metabo quality. 

The design of this drill is what sets it apart. The traditional pistol grip
and D Handle are replaced by what appears to be an upside-down configuration
with the handle mounted to the top. This feature is actually an asset when
drilling in close quarters, keeping your hands away from the dirt when
drilling near the ground, but it's also cumbersome in overhead use. The
weight hanging underneath the handle takes getting used to, and it will take
more time to determine whether this is a better way of gripping a drill. 

The sleek outward appearance of the Metabo P7911 belies Porsche Design's
influence; carbon fibers and aluminum give the 7911 an air of a tool
designed for use on the International Space Station. If a drill could be
considered sexy, then the Metabo-Porsche design 7911 is Marilyn Monroe.

Power and size, the 7911 is the smallest of the hammers tested. The P7911 is
equipped with a two-speed 6.5 amp motor that can deliver up to 2,800 RPM and
4,600 hammer blows per minute. If you just go by the numbers, it's a little
better than the popular DeWalt D25203K, whose single-speed 7.5-amp motor
delivers a maximum 1,100 RPM and 4,100 BPM. But it also costs three times as
much and isn't (yet) available in the USA. The P7911 is compatible with a
wide variety of existing SDS Plus bits.



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