Clarke MIG220TE, Operating & Maintenance Instructions

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The Earth Clamp
Attach the earth clamp to the workpiece as close to the point of weld as possible, without it being
intrusive. Ensure there is good contact and if necessary, clean the area with a wire brush
beforehand.... Remember, the contact MUST be on bare metal - thoroughly clean.
The Gas Valve
Open the gas valve on the gas cylinder. Regulate the pressure by turning the regulator knob
clockwise (to increase pressure), and adjust to the desired setting.
NOTE: this varies with
different metals, thicknesses and currents. Refer to a MIG welding manual for instructions.
Your welder is now fully prepared for welding as follows:
With the welding current set, and welding wire trimmed, set the wire feed control to 6, (8 for
aluminium).
Plug the machine into the mains supply or switch on at the isolator and ensuring all precautions
have been taken and with the machine set up correctly, switch ON the machine and lower the
torch to the workpiece with one hand, whilst holding the welding mask in the other.
Approach the work with the tip at an angle of approx. 45
O
and pull the torch trigger fully. A welding
current is now available at the tip and gas will be issued.
As the wire touches the workpiece, an arc will be struck...... BEFORE it is struck, cover the face
with the face mask.
Maintain a gap of approx. 5 - 7mm from the workpiece to the tip, and feed the wire into the
molten pool at a steady rate, along the line of the proposed weld.
The speed of weld will depend upon the wire speed and welding current.
NOTES:
As MIG welding is an acquired skill, it is strongly advised that, if you are not fully
familiar with this type of welding, you practice on a piece of material with the
same characteristics as your workpiece, until you are satisfied with the result,
and you have fine tuned your welder to produce a satisfactory weld.
One of the problems experienced with novice welders, is the welding wire
sticking to the contact tip. This is as a result of the wire feed speed being too
slow. It is always better therefore to start with too high a speed, and back off
slightly, to avoid the possibility of the wire welding itself to the tip. This is the
reason position 6 is recommended for start up.
The Wire Feed control is for fine tuning the wire speed. The speed of wire
delivery will increase automatically as the current is increased from MIN to
MAX, and vice versa. Therefore, once the ideal speed is achieved, by fine
tuning, it should not be necessary to adjust this control when the welding
current is changed.
Listen to the sound made. An irregular crackling sound denotes too high a wire
speed. Decrease the speed until a regular, strong buzzing sound is heard.