Welding Defects - Cebora SOUND MIG 1660/M ALUMINIUM Manual De Instrucciones

wires, and with a "V"-shaped groove for other wires.
Based on the type of wire to be used, make sure that the
cables corresponding to the torch and earth clamp are pro-
perly connected to the terminal board accessible from the
door on the right-hand side of the machine.
Normally, with wires that require gas protection, the torch
must be connected to the (+) pole.
4.1.1 Connecting the gas hose
The gas cylinder must be equipped with a pressure regula-
tor and flow gauge.
If the gas cylinder is placed on the cylinder shelf of the trolley
(Art. 1441) it must be fastened using the chain provided.
Connect the gas hose leaving the rear of the machine to
the pressure regular, only after positioning the cylinder.
The gas flow must be adjusted to approximately 8-10
liters per minute.
4.2 THE MACHINE IS READY TO WELD
When using the Pull-2000 or Spool-Gun torch, follow the
instructions enclosed.
• Connect the earth clamp to the workpiece.
• Set the switch U to I.
• Remove the gas nozzle.
• Unscrew the contact tip.
• Insert the wire in the wire liner of the torch, making sure that
it is inside the roller groove and that the roller is in the correct
position.
• Press the torch trigger to move the wire forward until it
comes out of the torch.
• Caution: keep your face away from the gun tube
assembly while the wire is coming out.
• Screw the contact tip back on, making sure that the hole diameter is the same as that of the wire used.
• Assemble the gas nozzle.
4.3 WELDING CARBON STEEL
In order to weld these materials you must:
4.3.1 With gas protection
• Use a welding gas with a binary composition, usually
10
ARGON + CO2 with percentages of Argon ranging from
75% up. With this blend, the welding bead will be well join-
ted and attractive.
Using pure CO2 as a protection gas will produce narrow
beads, with greater penetration but a considerably increase
in splatters.
• Use a welding wire of the same quality as the steel to be
welded. It is best to always use good quality wires, avoiding
welding with rusted wires that could cause welding defects.
• Avoid welding rusted parts, or those with oil or grease
stains.
4.3.2 Without gas protection
To achieve well connected and protected welds, always
work from left to right and top to bottom. The flux-cored
wires Ø 0.9 Art. 1586 or Art.1587 must be used the with the
torch connected to the (-) pole.
4.4 WELDING STAINLESS STEEL
Series 300 stainless steels must be welded using a protec-
tion gas with a high Argon content, containing a small per-
centage of O2 or carbon dioxide CO2 (approximately 2%) to
stabilize the arc.
Do not touch the wire with your hands. It is important to keep
the welding area clean at all times, to avoid contaminating
the joint to be welded.
4.5 WELDING ALUMINUM
In order to weld aluminum you must use:
o Pure Argon as the protection gas.
o A welding wire with a composition suitable for the base
material to be welded.
o Use mills and brushing machines specifically designed for
aluminum, and never use them for other materials.
o In order to weld aluminum you must use the torches:
PULL 2000 Art. 1561 or SPOOL-GUN Art. 1562 with the
connection Art. 1196.

5 WELDING DEFECTS

1 DEFECT- Porosity (within or outside the bead)
CAUSES • Electrode defective (rusted surface)
• Missing shielding gas due to:
- low gas flow
- flow gauge defective
- regulator frosted due to no preheating of the
CO2 protection gas
- defective solenoid valve
- contact tip clogged with spatter
- gas outlet holes clogged
- air drafts in welding area.
2 DEFECT - Shrinkage cracks
CAUSES • Wire or workpiece dirty or rusted.
• Bead too small. • Bead too concave.
• Bead too deeply penetrated.
3 DEFECT - Side cuts
CAUSES • Welding pass done too quickly
• Low current and high arc voltages. 4 DEFECT - Excessive spraying
CAUSES • Voltage too high.