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28
Problem
Likely Reason
Outcome
Wire feed stutters and arc
is erratic. Also, motor turns
correctly under no load.
Torch consumables are
blocked/partially blocked.
Rusty MIG Wire.
Liners and contact tips
are consumable and wear
over time.
Replace the torch liner and
reduce wire feed tension.
Presence of porosity at
weld start.
The torch gas hose has not
been purged sufficiently.
Purge the system and
confirm sufficient gas flow
through the regulator.
GTAW/TIG Models
Tungsten burns up on arc
start.
The polarity of the electrode/
return cables is incorrect.
Gas not turned on
Gas flow too low
Not enough Pregas time
Polarity should be confirmed
for the process/wire type in use
Review gas set up.
The weld has small
black ‘lumps’ or ‘dots’
appearing in the pool.
Cleaning is poor.
Old or dirty filler rods can
often be the cause of ‘dirty’
TIG welding operations.
Switching filler rods to
another type or batch may
solve this issue.
Weld is contaminated with
small bubbles (presence
of porosity).
The gas hose is not securely
connected at the machine or
at the regulator.
Ensure the gas connections
from regulator through to the
torch connection are
sufficiently tightened.
Presence of porosity at
weld start.
The torch gas hose has not
been purged sufficiently.
Purge the system and
confirm sufficient gas flow
through the regulator.