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WELDING BASICS
When you weld external influences play a large part in what type of result you are
going to get. These external influences are sometimes mistaken for machine faults.
Below is a list of effects that you may come across and their possible causes.
POROSITY This is when small holes appear in the weld. This is caused by the gas
during the welding process coming into contact with other gases within the metal
being welded. This can be rectified by grinding the weld back and cleaning the work
piece, ensuring that the gas flux is set to 8 litres per minute and incline the torch
while welding.
SPATTER This is when small balls of molten metal come out of the arc. A little
amount is unavoidable but by selecting the correct settings including gas glow and
ensuring the welding torch is clean it should be kept to a minimum.
NARROW HEAP WELDING This can caused by moving the torch to fast.
VERY THICK OR WIDE WELDING This can be caused by moving the torch too
slowly.
WIRE BURNS BACK This can be cause by the wire feed slipping, being loose, hav-
ing a damaged welding tip, wire quality, the voltage being to high or the nozzle
being held to close to the work piece.
POOR PENETRATION This can be caused by moving the torch over the work piece
to fast, low voltage or incorrect wire speed. To rectify this adjust the settings and
clean the work piece.
WORK PIECES PIERCING This can be caused by moving the torch too slowly, the
voltage being to high or by incorrect wire speed.
WELDING ARC INSTABILITY This may be caused by incorrect voltage, wire
speed or gas speed.
THERMAL OVERLOAD
This welder is fitted with a thermal overload cut out which operates automatically to
stop the transformer overheating which may cause damage to the welder.
The welder will become operational again automatically once the temperature has
reduced itself to an acceptable working temperature.
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