Harbor Freight Tools 95136 - Manual (Page 12)

Page 12 For technical questions, please call 1-800-444-3353. SKU 95136
SAFETY
SER
VICE
OPERA
TION
TECHNIQUES
SETUP
Technique
Using a plasma cutter is a skill that requires time and
effort to do well. Practice striking and maintaining
an arc on scrap work pieces before beginning
work. This will help you gauge the best settings
for the plasma cutter for the material at hand.
1. You can cut any metal that will conduct
electricity up to approximately ½″ thick mild
steel or equivalent. Very thin or very thick
metals are more difficult to cut cleanly.
2. Generally set the air pressure between 60 and
80 psi. Increased air pressure will increase
plasma speed and cutting pressure. Air pressure
and amperage should be adjusted in tandem.
3. Generally start with a mid-range amperage
setting (32-33 amps) and adjust up or down
from there. Increased amperage will increase
cutting heat. This is needed with heavier and
harder metals. However, increased amperage
will reduce Duty Cycle time. (See page 6.)
4. Move the cutting head more slowly for thicker and
harder metals, and more quickly for thin or soft
metals. Keep the cutting head moving while cutting.
How Plasma Cutters Work
Plasma cutters work by feeding an inert gas (air)
through an electric arc. The air is then heated to
an extremely high temperature which converts
the gas to plasma which cuts the metal.
High temperature and pressure are required to create
a plasma. The electric arc provides the temperature,
and by exhausting the air through a very small
orifice, the pressure is increased far beyond the
60-80 PSI operating pressure of the air supply.
What is Plasma?
Materials in Nature exist in one of four different
states: Solid, Liquid, Gas or Plasma. Plasma is very
rare on Earth because of its very high temperature,
however most of the matter in the universe is plasma.
The Sun, stars and galaxies are made of plasma.
On Earth, you will find plasma in lightning and a
few other places. Neon tubes and florescent lights
contain low-temperature plasma when lighted.
The difference between water ice, liquid water and
water vapor is temperature. In each of these states,
temperature energy pushes the molecules of water
away from each other to change the state the water
is in. At very high temperature and pressure the water
molecules themselves break apart, and the atoms
begin to ionize. Normal atoms are made up of protons
and neutrons in the nucleus, surrounded by a cloud of
electrons. In plasma, the electrons separate from the
nucleus. The electrons are negatively charged, and
they leave behind their positively charged nuclei which
are known as ions. When the fast-moving electrons
collide with other electrons and ions, they release
vast amounts of energy. This energy is what gives
plasma its unusual status and great cutting power.