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The advantages
of masonry table saws
They are safer and more controllable and allow higher productivity
By Richard Mancinelli
hen it comes to cutting masonry units, you
have several choices—a right angle grinder, a
cut-off saw, a paver saw, a portable masonry
table saw, or a full-size masonry table saw. For cutting a range of masonry materials, the masonry table
saw has three distinct advantages: greater operator
safety, better cutting control, and higher production
capacity.
Though it may require a couple of workers to load
and unload, a masonry table saw provides the operator with a stable, safe work surface and can be fitted
with a wheel kit for transporting around the jobsite.
Some saws now have forklift brackets on the back
and sides to allow the saw to be placed in the best location easily. Table saws can cut either dry or wet,
with a diamond blade or an abrasive blade, using a
gas engine or an electric motor.
W
Target
Foot pedals allow the operator to
have both hands on the masonry
unit. (Note: Saw operators should
follow the safety suggestions in
the box on page 39.)
Saw manufacturers provide equipment
safety information
The Construction Industry Manufacturers Association (CIMA) has developed several safety and information brochures dealing with masonry, concrete, and
hand-held (gasoline-powered) abrasive saws. The
CIMA booklets were produced by the Masonry and
Concrete Saw Manufacturers Institute (SMI), whose
members are manufacturers of equipment used to
cut, drill, or grind masonry, concrete, stone, or other construction materials.
Among the SMI materials offered for owners and operators of various types of saws are:
■ Warning Label—for affixing to saws
■ “Do’s and Don’ts” cartoon sheet—for users of diamond and abrasive wheels
■ “Rx for Concrete Saws”—safety instructions for general operation, machine and blade operation, applications, and maintenance
■ “Rx for Diamond Blade Safety”—safety instruction
for diamond-blade saws
■ “Rx for Diamond
Blades”—operational guidelines, causes, effects, and
remedies
■ “Rx for Gasoline-Powered,
Hand-Held Portable Abrasive
Cutting-Off Machines”— operational guidelines, causes, effects, and remedies
■ “Rx for Wall Saws”—covering special precautions,
mounting, cutting, operation,
and maintenance
For more information, contact Nicole Ketchman, Construction Industry Manufacturers Association, 111 E.
Wisconsin Ave., Suite 1000, Milwaukee, WI 53202 ( 414-2984129); e-mail nketchman@cim
anet.com or visit CIMA’s Web
site at www.cimanet.com.
Increased operator safety
The operator can also
lower the blade with the
hand lever.
MK Diamond Products
Saws are inherent safety risks. But a table saw
minimizes the dangers in comparison to hand-held
saws (see box below). A benefit of a masonry table
saw is the ability to easily switch from wet cutting to
dry cutting. Wet cutting helps reduce dust, but it also
soaks the masonry unit, which could lead to color
changes in the mortar or lower bond strength when
a wet unit is used.
Masonry table saws help minimize operator fatigue, which increases safety. One feature that contributes to easier use is the ability to let the saw operator use either the handle grip or foot pedals to
lower the blade into the cut. Alternatively, the operator can lock the head into a stationary position and
push the material toward the blade on the conveyor
cart. The cart is a critical part of the table saw; some
manufacturers offer conveyor cart wheels made of
nylon, while other companies use metal. Though nylon wheels are less expensive, they also require
more frequent replacement due to nicks or wear
from abrasive materials.
It’s important to remember that for saws with a
pivoting head the head supports not only the blade
but also the weight of the engine or motor. Some
saws have a metal-to-metal contact at the pivot
point, which can wear over time and require more
operator effort to lift and lower the head assembly
with each cut. Other saws have bearings that are
completely sealed, lubricated, and seated in a machined saddle, which allows smoother pivoting of the
blade-guard head assembly and requires less operator effort.
Greater cutting control
An electric- or battery-powered right angle grinder
is great for cutting masonry units
that are already set in place. A cutSaw safety
off saw can easily make a few quick
cuts that don’t need to be perfectly
To keep your saw operators as
unit at a time.
safe as possible, there are three
■ Never force the blade to cut faster
square. But in applications where
main things to consider: personal
than it will freely cut.
consistency and control are imporprotection, operational safety, and
■ If the blade binds, turn off the
tant, masonry table saws are the
site safety.
power to clear it.
right choice.
■ Don’t cut units that are cracked.
“Table saws offer a perfect cut evPersonal protection
■ While cutting, never put your finery time and are much safer than
gers inside cores, cells, or frogs,
considerations
or across the line of cutting, eithe hand-held saws,” says Phil
Each operator should have:
ther in front of or behind where
Franchino, purchasing and sales
■ hearing protection (Ear muffs
the blade will cut.
are best because they are highly
manager for Spartan Sales, Hillside,
visible.)
N.J. Spartan’s masonry customers
Site safety
■ safety glasses
are predominantly medium-to-large
■ Know the proper procedure in
■ steel-capped safety boots
masonry contractors. For cutting
case of an accident.
■ apron (optional, but will shield
masonry units, Spartan’s big sell■
Post
safety
reminders
on
all
saws.
the operator from water spray)
ers are electric-powered high-pro■ Assure that all saws have all
■ dust mask (essential for dry cutguards in place.
duction masonry table saws with
ting)
■ Keep power cables strung high
■ hard hat
20-inch blades. “On production
enough to prevent interference
■ gloves (optional; many experts
jobs, table saws can save a lot of
with other workers or equipment.
recommend against using gloves
time, with one man feeding blocks
■ Use no extension cords longer
around saw blades)
to the saw and another bringing
than 100 feet long.
them up to the scaffolding,” says
■
Practice
good
housekeeping
Operational safety
Franchino. “Production, reliability,
around the saw.
■ Know where the emergency cut■ Inspect the saw every day before
and strength are what our cusoff switch is.
starting it.
■ Ensure that the power is off betomers want. The electric saws can
■ Allow only properly trained operfore changing blades.
be wired at the job, they typically
ators to use saws.
■ Make sure that the masonry units
don’t break, there’s no oil or gas to
are flat on the cart, and hold them
fill, and they make less noise.”
Reference
firmly against the conveyor cart.
In high-production situations, a
This information was excerpted
■ Don’t be afraid to get wet from
14-inch or 20-inch masonry saw profrom The Masonry Saw by William
blade spray.
Hick, 1999, Construction and Transvides the control and horsepower
■ Do not try to cut more than one
port Educational Services Division,
to cut quickly, and there are many
masonry table saw choices to fit
Production-oriented
Though it may be tempting to use the least expensive saw to cut masonry units, cheaper does not
mean faster. This is especially true for jobs requiring a more production-oriented saw. Cut-off saws, for
example, are much less expensive and more portable
than table saws, but if you have to make more than
a few cuts, it becomes difficult to bend over for each
cut with a 30-pound hand-held saw.
In many cases, production must be a trade-off for
versatility and portability. “Portability is the most
important thing to our customers, who are mainly
general masons,” says Steve Boyce, a salesperson
at Anchor Concrete Products in Brick, N.J., which
sells a lot of concrete pavers and block materials. To
Attached to a shop vac,
this new dust-free saw can
cut wet or dry (Note: Saw
operators should follow the
safety suggestions in the
box on page 39.)
EDCO Equipment Development
any size job. For example, portable 11⁄2-horsepower
table saws can run on 15-amp household circuits
and are perfect for one-mason jobs, jobsites with
tight quarters, when cuts are being made on the scaffolding, or on residential masonry jobs. For larger
jobs, higher-horsepower production masonry table
saws have either engines or motors. A new development, removable power platforms allow saw operators to quickly convert from a high-horsepower
electric motor to a gasoline engine.
The top considerations in evaluating masonry
table saws are the size of the motor and the material
to be cut, according to Royce Brock, superintendent of bricklayers for Kansas City-based JE Dunn.
Brock supervises a team of 147 masons and a fleet of
22 electric masonry table saws.
Typically, more is better when it comes to horsepower, since more power allows faster cuts. But
there are other factors to balance when evaluating
masonry saws, such as fuel consumption and emissions from gasoline-powered saws. With an electric
saw, choosing the right horsepower can be a bit
tricky. An electric motor’s horsepower is influenced
by power fluctuations from a generator and by the
distance between the power source and the saw.
The available voltage at a jobsite will also be a major
consideration, since some saws are wired to run on
115 or 230 volts, and the higher horsepower saws
run on 230- or 460-volt, three-phase power.
“When I choose a saw from the fleet to take to the
jobsite, I look at the size of the motor,” says Brock.
“The power source dictates where we put the saw.
Some of ours have 3-hp motors, and some have 5hp motors. On jobs where we use a generator, the
saw might run continuously for half a day, so we use
the 3-hp saws.” As a general contractor, JE Dunn usually shares its generators with subcontractors on
the job. To maximize power from the generator,
Brock might choose a smaller horsepower saw, and
he never uses extension cords more than 100 feet
long.
determine whether a customer needs a cut-off saw
or a table saw, he asks these questions:
■ What materials are you cutting?
■ Are you cutting wet or dry?
■ What are the field applications?
■ What is the water source?
■ How frequently will the saw be used?
An emerging trend in building materials is bigger
block. For these masonry units, the best option is a
20-inch production saw that can make an 8-inch-maximum depth of cut. This can reduce cutting time by
half, when compared to a 14-inch blade saw that can
make only a 5-inch-deep cut. This time-saving is possible because, with a 20-inch blade, you can cut
8x8x16-inch blocks in one pass rather than flipping
them over for a second pass.
However, on larger buildings, architects may specify masonry units as large as 12x12x24 inches. For
cutting these materials, you’ll need to make two
passes through the saw; some 20-inch saws have an
extended frame that allows you to pass the material completely through the blade. This speeds production and can also help reduce operator fatigue.
To help masons cut larger block, saw manufacturers
have begun to offer larger carts or side-support extensions for conveyor carts to ensure the masonry
material is fully supported as the blade cuts.
Masonry table saws not only have an advantage in
production capacity, but also they’re very durable by
design. “I have a 20-inch saw sitting in my barn that
was handed down from my dad,” says Brock. “I’m not
sure how old it is, but it can still cut brick, and I use
it around the house. I think that’s the best thing;
they just keep running.”
Publication #M99I038
Copyright© 1999, The Aberdeen Group,
a division of Hanley-Wood, Inc.
All rights reserved