22
POWER TOOL OPERATION
Many applications and accessories will provide the best
performance at full speed, but for certain materials,
applications, and accessories, you need slower speeds,
which is the reason for a variable speed tool.
Ultimately, the best way to determine the correct speed for
work on any material is to practice for a few minutes on a
piece of scrap, even after referring to the chart. You can
quickly learn that a slower or faster speed is more effective
just by observing what happens as you make a pass or two
at different speeds. When working with plastic, for example,
start at a slow rate of speed and increase the speed until
you observe that the plastic is melting at the point of contact.
Then reduce the speed slightly to get the optimum working
speed.
Some rules of thumb in regard to speed:
1. Plastic and other materials that melt at low temperatures
should be cut at low speeds.
2. Polishing, buffing and cleaning with any type of bristle
brush must be done at speeds not greater than 15,000
RPM to prevent damage to the brush.
3. Wood should be cut at high speed.
4. Iron or steel should be cut at high speed. If a high-speed
steel cutter starts to chatter — this normally means it is
running too slow.
5. Aluminum, copper alloys, lead alloys, zinc alloys and
tin may be cut at various speeds, depending on the type
of cutting being done. Use paraffin or other suitable
lubricant on the cutter to prevent the cut material from
adhering to the cutter teeth. Increasing the pressure on the
tool is not the answer when it is not performing as you think
it should. Perhaps you should be using a different accessory,
and perhaps an adjustment in speed would solve the
problem. Leaning on the tool does not help.
Using the Rotary Tool
The first step in learning to use the Rotary Tool is to get the
“feel” of it. Hold it in your hand and feel its weight and
balance.
Always hold the tool away from your face. Accessories can
be damaged during handling, and can fly apart as they
come up to speed. This is not common, but it does happen.
CAUTION:
Whenever you hold the tool, be careful not to
cover the air vents with your hand. This blocks the air flow
and causes the motor to overheat.
For best control in close work, grip the Rotary Tool like a
pencil between your thumb and forefinger (Figure A on next
page).
The “Golf Grip” method of holding the tool is used for more
aggressive operations such as grinding a flat surface or
using cutoff wheels (Figure B on next page).
