Impax IM-MIG120 Instruction Manual page 33

MIG TROUBLESHOOTING
PROBLEM
Burning through – Holes
within the material where
no weld exists.
Poor fusion – Failing of
weld material to fuse
either with the material to
be welded or previous
weld beads
Irregular weld bead and
shape
Your weld is cracking
POSSIBLE CAUSE
Heat input too high.
Insufficient heat level
Poor welding technique
Work piece dirty
Incorrect voltage.
If it's convex, voltage is too low
and if it's concave then voltage is
too high.
Insufficient or excessive heat input
Wire is wandering
Incorrect shielding gas
The weld beads too small
Weld penetration narrow and deep
Excessive voltage
Weld/material cooling rate too fast
32
REMEDY
Use lower amperage or smaller
electrode.
Use correct welding travel speed
Increase the amperage or increase
the electrode size and amperage
Joint design must allow for full access
to the root of the weld
Alter welding technique to ensure
penetration such as weaving, arc
positioning or stringer bead technique
Remove all contaminant from the
material i.e. oil, grease, rust, moisture
prior to welding
Adjust voltage
Adjust the voltage control
Replace contact tip
Check and change the shielding gas
as required
Try decreasing the travel speed
Try reducing voltage or increase MIG
torch travel speed
Decrease voltage control dial
Slow the cooling rate by preheating
part to be welded or cool slowly