Tweco PCM - 102 Machine Torch - Manual (Page 29)

Manual 0-2818 4-5 OPERATION
C. Drag Cutting With a Hand Torch
Drag cutting works best on metal 3/16" (4.7 mm) thick or
less.
NOTE
For best parts performance and life, always use
the correct parts for the type of operation.
1. Install the drag cutting tip and set the output current
to 35 amps or less.
2. The torch can be comfortably held in one hand or
steadied with two hands. Position the hand to
press the Trigger on the torch handle. With the
hand torch, the hand may be positioned close to
the torch head for maximum control or near the
back end for maximum heat protection. Choose
the holding technique that feels most comfortable
and allows good control and movement.
3. Keep the torch in contact with the workpiece dur-
ing the cutting cycle.
4. Press the Torch Trigger, and after an initial two
second pre-flow, the pilot arc will come on and
remain on until the cutting arc starts.
5. Once on, the main arc remains on as long as the
Torch Trigger is held down, unless the torch is
withdrawn from the work or torch motion is too
slow. If the cutting arc is interrupted, the pilot
arc comes back on automatically.
NOTE
Most cutting is performed with the power supply
in the RUN position. For specific applications,
the LATCH position may be preferred where the
Torch Trigger can be released after the main arc
transfer. In the LATCH position, the torch remains
activated until the main arc breaks from the work-
piece.
6. To shut off the torch simply release the Torch Trig-
ger. When the Trigger is released a 20 second post-
flow will occur. If the Torch Trigger is pushed
during the post-flow, the cutting arc will restart
immediately when the torch is brought within
range of the workpiece.
D. Piercing With Hand Torch
1. The torch can be comfortably held in one hand or
steadied with two hands. Position the hand to
press the Trigger on the torch handle. With the
hand torch, the hand may be positioned close to
the torch head for maximum control or near the
back end for maximum heat protection. Choose
the technique that feels most comfortable and al-
lows good control and movement.
NOTE
The tip should never come in contact with the work-
piece except during drag cutting operations.
2. Angle the torch slightly to direct blowback par-
ticles away from the torch tip (and operator) rather
than directly back into it until the pierce is com-
plete.
3. In a portion of the unwanted metal start the pierce
off the cutting line and then continue the cut onto
the line. Hold the torch perpendicular to the work-
piece after the pierce is complete.
4. 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.