Torch; Pilot Arc Discussion; Procedure Recommendations - Lincoln Electric Tomahawk 1000 Operator's Manual

TOMAHAWK ® 1000
Applications:
Removing weld imperfections – cracks, porosity, inclusions, etc.
Back gouging for welding preparation
Removal of temporary fit up methods – tack welds, bracketing,
etc.
WARNING
ELECTRIC SHOCK CAN KILL.
• Turn off machine at the disconnect switch
on the rear of the machine before
tightening, cleaning or replacing
consumables.

TORCH

• Clean spatter and scale from the nozzle frequently.
• During operation, if the Parts in Place Yellow LED light
together:
• Check the assembly of the torch consumables. If they are not
properly in place, the machine will not start. Make sure that
the shield cup is hand tight. Do not use pliers or over tighten.
• Check the conditions on the inside of the nozzle. If debris has
collected, rub the inside of the nozzle to remove any oxide
layer that may have built up. Refer to "Suggestions for Extra
Utility from the Tomahawk
• Check the condition of the electrode. If the end has a crater-
like appearance, replace it along with the nozzle. The
maximum wear depth of the electrode is approximately .062".
A green and erratic arc will indicate definite electrode failure
and the electrode should be replaced immediately.
• 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, the machine may need to be reset by turning the power
switch OFF and then ON again. (It is possible for electrical
noise to trip the safety circuit on rare occasions. This should
not be a regular occurrence.)
• If the machine does not reset or continues to trip, consult the
Troubleshooting Section.
• Use the proper cutting procedures referred to in Procedure
Recommendations.
® 1000 system".

PILOT ARC dISCUSSION

The Tomahawk ® 1000 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 intermittently.
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 ® 1000 does not utilize high frequency starting.
When the pilot arc is started, a slight impulse will be felt in the
torch handle. This occurrence is normal and is the mechanism
which starts the plasma arc. This impulse can also be used to help
troubleshoot a "no start" condition.

PROCEdURE RECOmmENdATIONS

When properly used, plasma arc cutting is a very economical
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 vertical 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"
B-7
OPERATION
1/16" Standoff
Standoff