
5 
FUNCTIONAL DESCRIPTION 
 
CAUTION: 
• Always be sure that the tool is switched off and 
unplugged before adjusting or checking function on 
the tool. 
Switch action 
Fig.1 
CAUTION: 
• Before plugging in the tool, always check to see 
that the slide switch actuates properly and returns 
to the "OFF" position when the rear of the slide 
switch is depressed. 
• Switch can be locked in "ON" position for ease of 
operator comfort during extended use. Apply 
caution when locking tool in "ON" position and 
maintain firm grasp on tool. 
To start the tool, slide the slide switch toward the "I (ON)" 
position. For continuous operation, press the front of the 
slide switch to lock it. 
To stop the tool, press the rear of the slide switch, then 
slide it toward the "O (OFF)" position. 
Permissible shearing thickness 
Fig.2 
The groove on the yoke serves as a thickness gauge for 
shearing mild or stainless steel plate. If the material fits 
within the groove, it is shearable. 
The thickness of materials to be sheared depends upon 
the type (strength) of the material. The maximum 
shearing thickness is indicated in the table below in 
terms of various materials. Attempting to shear materials 
thicker than indicated will result in tool breakdown and/or 
possible injury. Keep within the thickness shown in the 
table. 
Material Max. cutting thickness 
(mm)
Tensile Strength 
(N/mm
2
)
Mild steel (A) 400 1.6 (16 ga)
Hard steel (B) 600 1.2 (18 ga)
Stainless steel 800 0.8 (22 ga)
Aluminum plate 200 2.5 (13 ga)
 
006425 
ASSEMBLY 
 
CAUTION: 
• Always be sure that the tool is switched off and 
unplugged before carrying out any work on the tool. 
Blade inspection 
Before using the tool, check the blades for wear. Dull, 
worn blades will result in poor shearing action, and the 
service life of the tool will be shortened. 
Rotating or replacing blades 
Both the upper and lower blades have four cutting edges 
on each side (the front and back). When the cutting edge 
becomes dull, rotate both the upper and the lower blades 
90° to expose new cutting edges. 
When all eight edges are dull on both the upper and 
lower blades, replace both blades with new ones. Each 
time blades are rotated or replaced, proceed as follows. 
Fig.3 
Remove the blade securing bolts with the hex wrench 
provided and then rotate or replace the blades. 
Fig.4 
Some tools have one washer between the upper blade 
and the blade holder.When the tool has the washer, be 
sure to use the thin washer when reassembling. 
 
NOTE: 
• No thin washers are used for the lower blade. 
Fig.5 
Install the upper blade and tighten the upper blade 
securing bolt with the hex wrench. Press up on the upper 
blade while tightening it. 
Fig.6 
After securing the upper blade, be sure that there is no 
gap left between the upper blade and the beveled 
surface of the blade holder. 
Fig.7 
When installing the lower blade onto the yoke, the lower 
blade should be pressed against the yoke so as to be 
contacting the beveled portions A and B of the yoke and 
the tip C of the lower blade positioning screw while you 
tighten the lower blade securing bolt. There must be no 
clearance between A, B and C during installation. 
 
NOTE: 
• The lower blade positioning screw is 
factory-assembled. Do not tamper with it. 
Fig.8 
OPERATION 
Holding material and shearing method 
 
WARNING: 
• Before operating the tool, be sure to firmly tighten 
the upper blade securing bolt and the lower blade 
securing bolt. Loosen bolts may cause blades 
coming off, resulting in a serious injury. 
• When cutting, always place the shear on the 
workpiece so that the material cut away is 
positioned on the right side to the operator. 
The materials for cutting should be fastened to the 
workbench by means of workholders. 
Fig.9 
Always hold the tool firmly with one hand on housing. Do 
not touch the metal part. 
Keep the shear moving parallel with the material.