CUTMASTER A80, A120
OPERATION 4T-4 Manual 0-5119
Bottom Dross Buildup
Molten material which is not blown out of the
cut area and resolidifies on the plate. Excessive
dross may require secondary cleanup operations
after cutting.
Kerf Width
The width of the cut (or the width of material
removed during the cut).
Top Spatter (Dross)
Top spatter or dross on the top of the cut caused by
slow travel speed, excess cutting height, or cutting
tip whose orifice has become elongated.
4T.05 General Cutting Information
WARNINGS
Disconnect primary power at the source before
disassembling the power supply, torch, or torch
leads.
Frequently review the Important Safety
Precautions at the front of this manual. Be
sure the operator is equipped with proper
gloves, clothing, eye and ear protection.
Make sure no part of the operator’s body
comes into contact with the workpiece while
the torch is activated.
CAUTION
Sparks from the cutting process can cause
damage to coated, painted, and other surfaces
such as glass, plastic and metal.
NOTE
Handle torch leads with care and protect them
from damage.
Piloting
Piloting is harder on parts life than actual cutting
because the pilot arc is directed from the electrode
to the tip rather than to a workpiece. Whenever
possible, avoid excessive pilot arc time to improve
parts life.
Torch Standoff
Improper standoff (the distance between the torch
tip and workpiece) can adversely affect tip life as
well as shield cup life. Standoff may also signifi-
cantly affect the bevel angle. Reducing standoff
will generally result in a more square cut.
Edge Starting
For edge starts, hold the torch perpendicular to
the workpiece with the front of the tip near (not
touching) the edge of the workpiece at the point
where the cut is to start. When starting at the edge
of the plate, do not pause at the edge and force the
arc to "reach" for the edge of the metal. Establish
the cutting arc as quickly as possible.
Direction of Cut
In the torches, the plasma gas stream swirls as it
leaves the torch to maintain a smooth column of
gas. This swirl effect results in one side of a cut
being more square than the other. Viewed along
the direction of travel, the right side of the cut is
more square than the left.
Side Characteristics Of Cut
To make a square - edged cut along an inside
diameter of a circle, the torch should move coun-
terclockwise around the circle. To keep the square
edge along an outside diameter cut, the torch
should travel in a clockwise direction.
Dross
When dross is present on carbon steel, it is com-
monly referred to as either “high speed, slow
speed, or top dross”. Dross present on top of
the plate is normally caused by too great a torch
to plate distance. "Top dross" is normally very
easy to remove and can often be wiped off with
a welding glove. "Slow speed dross" is normally
present on the bottom edge of the plate. It can vary
from a light to heavy bead, but does not adhere
tightly to the cut edge, and can be easily scraped
off. "High speed dross" usually forms a narrow
bead along the bottom of the cut edge and is very
difficult to remove. When cutting a troublesome
steel, it is sometimes useful to reduce the cutting
speed to produce "slow speed dross". Any resul-
tant cleanup can be accomplished by scraping,
not grinding.