Maktec MT622, Instruction Manual

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6
FUNCTIONAL DESCRIPTION
CAUTION:
• Always be sure that the tool is switched off and
unplugged before adjusting or checking function on
the tool.
Switch action
CAUTION:
• Before plugging in the tool, always check to see that
the switch trigger actuates properly and returns to the
“OFF” position when released.
For Model MT621 (Fig. 1)
CAUTION:
• 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, simply pull the switch trigger. Tool speed
is increased by increasing pressure on the switch trigger.
Release the switch trigger to stop.
For continuous operation, pull the switch trigger, push in
the lock button and then release the switch trigger.
To stop the tool from the locked position, pull the switch
trigger fully, then release it.
For Model MT622 (Fig. 2)
CAUTION:
• Change the direction of rotation only when the tool
comes to a complete stop. Changing it before the tool
stops may damage the tool.
The switch is reversible, providing either clockwise or
counterclockwise rotation. To start the tool, simply pull the
lower part of the switch trigger for clockwise or the upper
part for counterclockwise. Release the switch trigger to
stop.
ASSEMBLY
CAUTION:
• Always be sure that the tool is switched off and
unplugged before carrying out any work on the tool.
Installing top grip (auxiliary handle)
(Fig. 3)
Screw the top grip on the tool securely.
Installing back grip (country specific)
Pull off the cap from the tool housing. Insert the leaf
springs into the groove of the handle part that has the
bosses. Then attach them to the bottom of the tool
housing. (Fig. 4)
Attach both of the handle parts and tighten them with the
screws securely. (Fig. 5)
Installing or removing drill bit (Fig. 6)
To install the bit, place it in the chuck as far as it will go.
Tighten the chuck by hand. Place the chuck key in each
of the three holes and tighten clockwise. Be sure to
tighten all three chuck holes evenly.
To remove the bit, turn the chuck key counterclockwise in
just one hole, then loosen the chuck by hand.
After using the chuck key, be sure to return to the original
position.
OPERATION (Fig. 7)
Drilling operation
Always use the top or back grip (auxiliary handle) and
firmly hold the tool by top or back grip and switch handle
during operations.
Drilling in wood
When drilling in wood, the best results are obtained with
wood drills equipped with a guide screw. The guide screw
makes drilling easier by pulling the bit into the workpiece.
Drilling in metal
To prevent the bit from slipping when starting a hole,
make an indentation with a center-punch and hammer
at the point to be drilled. Place the point of the bit in the
indentation and start drilling.
Use a cutting lubricant when drilling metals. The
exceptions are iron and brass which should be drilled dry.
CAUTION:
• Pressing excessively on the tool will not speed up
the drilling. In fact, this excessive pressure will only
serve to damage the tip of your bit, decrease the tool
performance and shorten the service life of the tool.
• There is a tremendous twisting force exerted on the
tool/bit at the time of hole breakthrough. Hold the tool
firmly and exert care when the bit begins to break
through the workpiece.
• A stuck bit can be removed simply by setting the
reversing switch to reverse rotation in order to back
out. However, the tool may back out abruptly if you do
not hold it firmly. (For Model MT622)
• Always secure small workpieces in a vise or similar
hold-down device.
• Avoid drilling in material that you suspect contains
hidden nails or other things that may cause the bit to
bind or break.
MAINTENANCE
CAUTION:
• Always be sure that the tool is switched off and
unplugged before attempting to perform inspection or
maintenance.
• Never use gasoline, benzine, thinner, alcohol or the
like. Discoloration, deformation or cracks may result.
Replacing carbon brushes
Remove and check the carbon brushes regularly.
Replace when they wear down to the limit mark. Keep the
carbon brushes clean and free to slip in the holders. Both
carbon brushes should be replaced at the same time.
Use only identical carbon brushes. (Fig. 8)
Use a screwdriver to remove the brush holder caps. Take
out the worn carbon brushes, insert the new ones and
secure the brush holder caps.
(Fig. 9)
To maintain product SAFETY and RELIABILITY,
repairs, any other maintenance or adjustment should be
performed by Makita Authorized Service Centers, always
using Makita replacement parts.