Thermal Dynamics cutmaster A60, Service Manual

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CUTMASTER A60
Manual 0-4982 4T-1 OPERATION
SECTION 4 TORCH:
OPERATION
4T.01 Machine and Automated Torch
Operation
Cutting With Machine or Automated Torch
These torches are activated by remote control pen-
dant or by a remote interface device such as CNC.
1. To start a cut at the plate edge, position the
center of the torch along the edge of the
plate.
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 direc-
tion as torch travel.
Standoff Distance
Straight Arc
Trailing Arc
Leading Arc
Direction of Torch Travel
A-02586
Automation and 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.
Piercing With Machine or Automated Torch
To pierce, the arc should be started with the torch
positioned as high as possible above the plate while
allowing the arc to transfer and pierce. This standoff
helps avoid having molten metal blow back onto the
front end of the torch.
When operating with a cutting machine, a pierce or
dwell time is required. Torch travel should not be
enabled until the arc penetrates the bottom of the
plate. As motion begins, torch standoff should be
reduced to the recommended 1/8 - 1/4 inch (3-6
mm) distance for optimum speed and cut quality.
Clean spatter and scale from the shield cup and the
tip as soon as possible. Spraying or dipping the
shield cup in anti - spatter compound will minimize
the amount of scale which adheres to it.