Lincoln Electric IM10020 TOMAHAWK 625 - Manual (Page 17)

PROCEDURE RECOMMENDATIONS
When properly used, plasma arc cutting is a very eco-
nomical process. Improper use will result in a very
high operating cost.
General - In All Cases
• Follow safety precautions as printed throughout this
operating manual and on the machine.
• If piercing is required, slowly lower the torch at an
angle of about 30° to blow the dross away from
the torch tip and slowly rotate the torch to a ver-
tical position as the arc becomes deeper. This
process will blow a lot of molten metal and
dross. Be careful! Blow the dross away from
the torch, the operator and any flammable
objects.
• The nozzle should not be dragged on the metal
surface. A drag spacer is provided to maintain a
consistant touch height. Refer to Touch Parts
Configurations in this Section.
• Where possible, start the cut from the edge of the
work piece.
• Keep moving! A steady speed is necessary. Do
not pause.
Torch Standoff
DRAG thru 1/16"
Standoff
1/16” Standoff
B-7 OPERATION B-7
• Replace the nozzle when the orifice exit is eroded
away or oval shaped.
• After the problem is found, or if there is nothing
apparently wrong, reset the machine by turning the
power switch OFF and then ON again. (It is possi-
ble for electrical noise to trip the safety circuit on
rare occasions. This should not be a regular occur-
rence.)
• If the machine does not reset or continues to trip,
consult the Troubleshooting Section.
• Use the proper cutting procedures referred to in
Procedure Recommendations.
PILOT ARC DISCUSSION
The TOMAHAWK™ 625 has a smooth, continuous
pilot arc. The pilot arc is only a means of transferring
the arc to the workpiece for cutting. Repeated pilot arc
starts, in rapid succession, is not recommended as
these starts will generally reduce consumable life.
Occasionally, the pilot arc may sputter or start inter-
mittently. This is aggravated when the consumables
are worn or the air pressure is too high. Always keep
in mind that the pilot arc is designed to transfer the arc
to the workpiece and not for numerous starts without
cutting.
The TOMAHAWK™ 625 does not utilize high frequen-
cy starting. When the pilot arc is started, a slight
impulse will be felt in the torch handle. This occur-
rence is normal and is the mechanism which starts the
plasma arc. This impulse can also be used to help
troubleshoot a "no start" condition.
TOMAHAWK™ 625