Impax IM-MIG120 Instruction Manual page 35

MMA ASSEMBLY & OPERATION
Set the amperage using the current control
knob, Fig.30, until the desired setting is reached.
Fig 30
The chart below is an indicator of the electrode
diameter and the corresponding welding
current. This is intended as a guide only as
results can vary depending on material, work
piece thickness, welding position and joint form.
Table 1
Electrode Welding
size (mm) voltage (V)
1.0 20.8 - 22.4
1.6 21.7 - 23.3
2.0 22.4 - 24.0
2.5 23.2 - 24.8
3.2 23.3 - 24.9
4.0 24.6 - 27.2
WARNING! Always wear a full welding mask,
welding gloves and protective clothing. Wear
goggles while chipping slag.
Note: If the machine stops at any time and the
overheat indicator on the front panel
illuminates, the thermal cutout has intervened.
This indicator will turn on when the machine is
overheated and the output has been disabled.
This normally occurs when the duty cycle of the
machine has been exceeded. Leave the machine
on to allow the internal components to cool.
When the indicator turns off, normal operation is
again possible.
Holding a face mask in front of your face stroke
the electrode point on the workpiece as if
striking a match. Maintain a steady gap between
the end of the electrode and the workpiece of
approximately 2mm (Fig.31).
Fig 31
Maintain this distance as constantly as possible
during the weld remember that the angle of the
electrode to the work piece must be 20-30°
(Fig.32).
Fig 32
Welding
current (A)
20 - 60
44 - 84
60 - 100
80 - 120
108 - 148
140 - 180
Do not hit the electrode on the workpiece as
this may damage the electrode. Withdraw with a
clean movement at the end of the welding run.
Note: This is the most difficult aspect for most
beginners. It is recommended that you practice
on some scrap material in order to get a feel of
the operation.
If the electrode is not withdrawn quickly enough
once the arc is primed, there is a possibility that
the electrode will weld itself to the workpiece.
Should this happen, give it a sharp tug to free it,
and try again. If this fails to free it, turn off the
machine immediately as it will quickly overheat.
If you withdraw the electrode too far once the
arc is primed, you will lose the arc and have to
try again.
34
2mm
20º-30º