CUTMASTER 20mm
Manual 0-5078
4T-7
OPERATION
4T.05 Gouging
!
WARNINGS
Be sure the operator is equipped with proper
gloves, clothing, eye and ear protection and that all
safety precautions at the front of this manual have
been followed. Make sure no part of the operator’s
body comes in contact with the workpiece when
the torch is activated.
Disconnect primary power to the system be-
fore disassembling the torch, leads, or power
supply.
CAUTION
Sparks from plasma gouging can cause damage
to coated, painted or other surfaces such as glass,
plastic, and metal.
Check torch parts. The torch parts must
correspond with the type of operation. Refer to
Section 4T.07, Torch Parts Selection.
Gouging Parameters
Gouging performance depends on parameters
such as torch travel speed, current level, lead angle
(the angle between the torch and workpiece), and
the distance between the torch tip and workpiece
(standoff).
CAUTION
Touching the torch tip or shield cup to the work
surface will cause excessive parts wear.
Torch Travel Speed
NOTE
Refer to Appendix Pages for additional information
as related to the Power Supply used.
Optimum torch travel speed is dependent on current
setting, lead angle, and mode of operation (hand or
machine torch).
Current Setting
Current settings depend on torch travel speed,
mode of operation (hand or machine torch), and the
amount of material to be removed.
Lead Angle
The angle between the torch and workpiece depends
on the output current setting and torch travel speed.
The recommended lead angle is 35°. At a lead angle
greater than 45° the molten metal will not be blown
out of the gouge and may be blown back onto the
torch. If the lead angle is too small (less than 35°),
less material may be removed, requiring more pass-
es. In some applications, such as removing welds or
working with light metal, this may be desirable.
35°
Workpiece
Torch Head
Standoff Height
A-00941_AB
Gouging Angle and Standoff Distance
Standoff Distance
The tip to work distance affects gouge quality and
depth. Standoff distance of 1/8 - 1/4 inch (3 - 6
mm) allows for smooth, consistent metal removal.
Smaller standoff distances may result in a severance
cut rather than a gouge. Standoff distances greater
than 1/4 inch (6 mm) may result in minimal metal
removal or loss of transferred main arc.
Slag Buildup
Slag generated by gouging on materials such as car-
bon and stainless steels, nickels, and alloyed steels,
can be removed easily in most cases. Slag does not
obstruct the gouging process if it accumulates to the
side of the gouge path. However, slag build - up can
cause inconsistencies and irregular metal removal if
large amounts of material build up in front of the
arc. The build - up is most often a result of improper
travel speed, lead angle, or standoff height.
ARC WELDING SUPPLIES - 07 847 7870
