Troubleshooting − Excessive Spatter; Troubleshooting − Porosity - MAC TOOLS MW135 Owner's Manual

7-8. Troubleshooting − Excessive Spatter
Possible Causes
Wire feed speed too high.
Voltage too high.
Electrode extension (stickout) too long.
Workpiece dirty.
Insufficient shielding gas at welding arc.
Dirty welding wire.
7-9. Troubleshooting − Porosity
Possible Causes
Insufficient shielding gas at welding arc.
Wrong gas.
Dirty welding wire.
Workpiece dirty.
Welding wire extends too far out of nozzle. Be sure welding wire extends not more than 1/2 in (13 mm) beyond nozzle.
Excessive Spatter − scattering of molten metal particles that
cool to solid form near weld bead.
Select lower wire feed speed.
Select lower voltage range.
Use shorter electrode extension (stickout).
Remove all grease, oil, moisture, rust, paint, undercoating, and dirt from work surface before
welding.
Increase flow of shielding gas at regulator/flowmeter and/or prevent drafts near welding arc.
Use clean, dry welding wire.
Eliminate pickup of oil or lubricant on welding wire from feeder or liner.
Porosity − small cavities or holes resulting from gas pockets
in weld metal.
Increase flow of shielding gas at regulator/flowmeter and/or prevent drafts near welding arc.
Remove spatter from gun nozzle.
Check gas hoses for leaks.
Place nozzle 1/4 to 1/2 in (6-13 mm) from workpiece.
Hold gun near bead at end of weld until molten metal solidifies.
Use welding grade shielding gas; change to different gas.
Use clean, dry welding wire.
Eliminate pick up of oil or lubricant on welding wire from feeder or liner.
Remove all grease, oil, moisture, rust, paint, coatings, and dirt from work surface before
welding.
Use a more highly deoxidizing welding wire (contact supplier).
Corrective Actions
Corrective Actions
S-0636
S-0635
OM-210 089 Page 33