Working as a carpenter, my medium is generally wood, but like
many builders, I often find myself cutting things like threaded
rod, metal roofing, steel studs, and rebar. While I typically
use a reciprocating saw or a circular saw with an abrasive
blade for such materials, the resulting cuts are slow and
usually a bit ragged. In search of a better method, I recently
tested DeWalt's DW934 Cordless Metal Cutting Circular Saw
(DeWalt, 800/433-9258, www.dewalt.com) on a collection of steel
tubing, angle iron, rebar, and sheet metal.
The DW934 metal-cutting saw looks a lot
like an ordinary cordless saw, except for a larger all-metal
guard. The substantial guard prevents metal slivers from
becoming airborne and prevents hang-ups on thin material.
Unfortunately, it also hampers visibility, and two little
windows meant to make the cut line easier to see don’t
Features and Operation
Flying metal particles can be hot and dangerous, so the DW934
has a heavy, all-metal blade guard that's noticeably wider than
the guards on wood-cutting cordless saws. The guard keeps most
of the flying metal chips under control, but it also reduces
visibility of the cut line. To improve visibility, DeWalt has
included two small windows in the guard, one on the front and
another on the side.
The saw's shoe adjusts easily for depth, and because it's made
of non-magnetic stainless steel, metal chips don't stick to it.
But it doesn't tilt, so if you need to make beveled or compound
cuts, keep that in mind.
An arbor lock helps with blade changes, and the blade wrench
is stored on the saw housing. Aside from spinning a little
slower (3,100 vs. 3,700 rpm), the saw is similar in appearance
and operation to DeWalt's 18-volt wood-cutting saw (model
Cutting Sheet Metal
Although I try to keep an open mind regarding new tools, I was
a little concerned about cutting heavy-gauge steel with a
carbide-tipped blade, so my first test was intentionally easy.
I used the saw to cut 24-gauge sheet metal. It does an
excellent job cutting straight lines, but like any circular
saw, cutting a slight curve with even the thinnest material
causes kickbacks, so I wouldn't recommend it. If you need to
make circular or curved cuts, this isn't the right tool.
After cutting the 24-gauge sheet metal, I cut some 26-gauge
spiral ductwork for a dust-collection system in my shop. It
produced nice clean cuts and worked faster than my previous
method, using a pneumatic cutoff tool with an abrasive
Six-inch spiral ductwork is tough to cut
by hand, but by working his way around the duct, the author was
able to make smooth cuts in under 30 seconds. Plunge cuts for a
wye branch weren't a problem, either.
Cutting Real Steel
After the initial testing on sheet metal and easily plowing
through some 1/2-inch rebar, I was confident that the saw was
up to cutting even heavier materials, so I set out to find its
limit. When it was unfazed by my next material, 1/8-inch angle
iron and bar stock, I tried high-strength, 3/16-inch-thick,
2-inch-square tubing. Although the saw is listed as having a 2
3/8-inch capacity, it lacked the power to cut all the way
through this in one pass. I managed to get through it by
cutting halfway through from one side and finishing with a
second pass from the other side. While the saw produced a
smooth cut, it was pretty slow, proving that it's not a
substitute for a metal-cutting chop saw.
Seeing your cut line with this tool is a challenge. The
viewing window in front of the blade guard is almost completely
useless, and the side window isn't much better. Instead, I
relied on the shoe's guide slot for directing cuts. While the
slot is effective for 3-inch or longer cuts, it doesn't help
with narrow pieces like bar stock and threaded rod. Trying to
make it easier to see my cut lines, I used a number of
different markers and crayons. Yellow marking crayons show up
best in the viewing window, and a lot of light helps, too. This
is one tool that would truly benefit from on-board
Visibility issues aside, the saw is an efficient,
well-designed tool for light to medium metal-cutting
applications. It cuts faster than an abrasive blade and is
easier to handle than a recip saw, especially with the
light-gauge steel and aluminum that I typically cut. While it's
not a replacement for a metal cutoff saw, it can cut steel
angle and pipe pretty well, and it works great for long
straight cuts in sheet metal.
I'm still on the fence about buying one. Even though it came
in handy more than I thought it would, I don't think I'd use it
enough to justify the cost. However, I'm sure the DW934 would
be great for hvac installers, electricians, plumbers, and
anyone else who cuts metal regularly.
The DeWalt 934 sells for about $370 and comes with two 18-volt
XR NiCad batteries, a 40-tooth carbide-tipped blade, and a
blow-molded case.Gary Godbersenis a carpenter and woodworker in northern