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Market Report: Sawing & cutting Hugely powerful Phil Mist suggests that the performance of the latest 36V cordless circular saws with Lithium-Ion batteries means the tools could replace their mains powered counterparts. Cordless tools have always suffered from a lack of power for some applications. As a result, the most popular products to date have been drill/drivers, followed by impact drills and drivers. With the possible exception of 24V SDS-Plus hammer drills, cordless tools have not figured widely in hire fleets. This is largely due to battery shortcomings. NiCad (nickel cadmium) batteries have a very limited maximum capacity for each cell. The advent of NiMH (nickel metal hydride) batteries offered some improvement and they are found on many 18V and 24V cordless tools. However, battery failure due to overuse, overloading, overheating and poor charging has been a recurrent problem, often because of the application for which they have been used. To drill a small hole or insert a screw is one thing, but to cut 50mm-thick timber using a cordless circular saw you need considerable power and the ability to keep the battery cool. Some manufacturers have produced 18V Lithium-Ion tools, such as Metabo, and Makita, which offers such products for specific applications. However, other major power tool companies have developed hugely powerful 36V tools. Their performance means that now, virtually anything is possible. Impossible to affect performance In recent hands-on testing of 36V cordless saws currently available, each machine was used for repeated cutting at a depth of 25mm in MDF. The results were impressive. Despite periods of severe overload, it proved virtually impossible to affect the cutting performance, although I did manage to engage the overload circuit on one machine, causing it to stop for a few seconds. I was actually unable to reduce the batteries’ reserves sufficiently to necessitate a recharge. I achieved 50 cuts with each machine without any sign of battery rundown. Such performance speaks for itself. Hilti’s (www.hilti.co.uk) WSC70-A36 has a 190mm-diameter tungsten carbide tipped (TCT) blade with a rather surprising 30mm bore, and offers a maximum depth of cut of 70mm at 90°. It can mitre to a maximum of 50mm. No-load speed is 4,000rpm and, using either the standard 24-tooth blade or the optional 42-tooth blade, almost any timber can be cut. A riving knife behind the blade prevents jamming and helps reduce power drain. Depth is set by means of a pivot action and the large locking lever to the left of the body is simple to operate. Slots on the left of the upper blade guard, just above the sole plate, enable the operator to see the line of cut, and a large front knob for the user’s left hand gives good control. A double slot parallel fence is supplied for accuracy. The machine has a magnesium alloy base and a dead man’s switch. Noise emissions are 97dB(A) sound pressure and 108dB(A) sound power, so hearing protection is necessary. Quoted vibration emissions are less than 2.6m/s2. Hilti claims that up to 400 cuts, 70mm deep, can be achieved without recharging. The tool weighs 5.8kg including battery (6kg with the fence). It benefits from Hilti’s lifetime warranty (which also covers the battery), a repair cost limit, and a two-year no-cost repair period. DeWalt’s
(www.dewalt.co.uk)
DC300
has
a
claimed
maximum
power
output
equivalent
to
940watts.
It
has
a
blade
diameter
of
184mm
and
no
riving
knife,
and
maximum
depth
of
cut
is
62mm.
The DC300 has slots on the left of its substantial alloy upper blade guard, an alloy sole plate that permits mitre adjustment up to 45°, and a tool-free outer flange for easy blade clamping. The fence has only one clamping position, and the dead man’s on/off switch has a double-action lever protruding from either side of the top handle. I found this tricky to operate with my index finger, but then I am left-handed. Right-handers could use their thumb to manipulate the lever. Noise emissions are 94dB(A) sound pressure and 105dB(A) sound power, and the quoted vibration figure is 1.8m/s2. Bosch’s GCS36V-Li is a 165mm-diameter saw, again with no riving knife, and should be available in the UK next month. I tested it briefly at a recent launch in Germany and it performed like a mains machine. The blade is on the opposite side of the tool to the others on test, and the saw cut 25mm man-made timber board and 50mm softwood with ease. Bosch (www.boschpowertools.co.uk) claims an increase of 30% in the cutting rate over similar 24V saws and, despite loading the blade heavily on a couple of occasions, the GCS36V0-Li continued cutting without pause. It weighs 4.7kg including the battery, which has electronic cell protection, a double-location lock to prevent accidental release, and a heat conductive housing. If this new breed of tools does not suffer technical problems, then I foresee that very soon the demand for electric mains powered circular saws will be virtually eliminated. A 36V Lithium-Ion battery removes the need for a 110V power tool and a transformer, and such convenience is a selling point that hirers can promote strongly. • Executive Hire News › Archives › June 2007 › Market Report › Hugely powerful
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