Tweco SL100 - Manual (Page 31)

Manual 0-2962 4-7 OPERATION
7. Clean spatter and scale from the shield cup and the
tip as soon as possible. Spraying the shield cup in
anti - spatter compound will minimize the amount
of scale which adheres to it.
4.08 Machine Torch Operation
A. Cutting With Machine Torch
The machine torch can be activated by remote control
pendant or by a remote interface device such as CNC.
1. Use a square to check that the torch is perpendicu-
lar to the workpiece to obtain a clean, vertical cut .
A-02585
Workpiece
Square
Pinch Block
Assembly
Checking Alignment
2. To start a cut at the plate edge, position the center
of the torch along the edge of the plate.
B. Travel Speed
Proper travel speed is indicated by the trail of the arc
which is seen below the plate. The arc can be one of
the following:
1. Straight Arc
A straight arc is perpendicular to the workpiece
surface. This arc is generally recommended for the
best cut using air plasma on stainless or aluminum.
2. Leading Arc
The leading arc is directed in the same direction as
torch travel. A five degree leading arc is generally
recommended for air plasma on mild steel.
3. Trailing Arc
The trailing arc is directed in the opposite direction
as torch travel.
Standoff Distance
Straight Arc
Trailing Arc
Leading Arc
Direction of Torch Travel
A-02586
Machine Torch Operation
For optimum smooth surface quality, the travel speed
should be adjusted so that only the leading edge of
the arc column produces the cut. If the travel speed
is too slow, a rough cut will be produced as the arc
moves from side to side in search of metal for transfer.
Travel speed also affects the bevel angle of a cut. When
cutting in a circle or around a corner, slowing down
the travel speed will result in a squarer cut. The power
source output should be reduced also. Refer to the
appropriate Control Module Operating Manual for any
Corner Slowdown adjustments that may be required.