Plasma Cutters For Sale
The process of plasma cutting metals is through the use of a gas (some units even use compressed air) which is
forced through a nozzle at high velocity through compression. Plasma cutters form an electrical arc across the gas
being forced through the nozzle. The electrical arc turns part of the gas into plasma. It is this gas plasma that
does the actual cutting. The gas not only does the cutting but is forced through the nozzle at such speed that the
melted metal is blown away from the cut.
Plasma Cutters for Sale Buying Tips
If you are searching for used plasma cutters for sale then you should be aware of the methods used to
start a plasma cutter. Older plasma cutters used a high voltage coupled with a high frequency to start the arc.
These types of units can cause electrocution and are difficult to repair. Another disadvantage is that these types
of units create a lot of high frequency radio transmissions and use of these types of units is not recommended
around sensitive electronic equipment.
For those uses, a contact start plasma cutter is recommended.
Older plasma cutters were analog type. That means they required a very large amount of power from the utility
companies and then used a transformer to convert the power to that necessary for the cutter along with the
proper frequency for causing the gas to become plasma.
Newer machines use inverter technology which converts the AC power from the utility companies to Direct Current
(DC). This DC current is then coupled with high frequency inverter. In most cases the higher the frequency, the
smaller the unit can be in weight and size. This is possible because higher frequencies mean more efficiency in the
plasma cutting machine.
If you plan on running your plasma cutter from a generator then you should read the manufacturers instructions
for the unit you are considering. Some manufacturers specifically prohibit running their machines from portable
generators. This is because some units do not have power factor correction built in to them. That type of
circuitry stabilizes the power to the plasma cutter.
Even though some newer units do not have power factor correction built in to them, they do use internal
circuitry to accomplish a similar task. In those types of units, the manufacturers do allow them to be powered from
Technology now allows some plasma cutters to operated with near laser accuracy. These models come with smaller
nozzles and utilize a much smaller diameter of gas. Some cut edges using these new nozzles have a near perfect, or
laser looking, cut edge.
The combining of these units with CNC control allows manufacturers to cut metals (or other materials)
with such precision that little or no finishing of the cut edges is necessary.
In the beginning, plasma cutting machines were very expensive. The older units did not use inverter
technology so they were large and heavy. The newer types of plasma cutters that use inverter technology weigh a
fraction of what the older units weighed and, in some cases, the newer, lighter units are more powerful.
When searching for plasma cutters for sale, do your homework to make sure the unit you are
looking to purchase has the capacity, power and portability you need to get your specific job done.
If you are looking at previously owned plasma cutters for sale then take your time and check the condtion, make
sure it has the technology you need to get the job done and if you plan on using a portable power source be sure it
is the type needed for the particular plasma cutters for sale you are looking at.