Hobart H-9B, 125 EZ Troubleshooting − Lack Of Penetration, Troubleshooting − Incomplete Fusion

8-11. Troubleshooting − Lack Of Penetration

		Lack Of Penetration − shallow
		fusion between weld metal and
		base metal.
Lack of Penetration	Good Penetration
		S-0638
Possible Causes		Corrective Actions
Improper joint preparation.	Material too thick. Joint preparation and design must provide access to bottom of groove while
	maintaining proper welding wire extension and arc characteristics.
Improper weld technique.	Maintain normal gun angle of 0 to 15 degrees to achieve maximum penetration.

	Keep arc on leading edge of weld puddle.
	Be sure welding wire extends not more than 1/2 in (13 mm) beyond nozzle.
Insufficient heat input.	Set Metal Thickness Selector switch to a higher selection.
	Reduce travel speed.

8-12. Troubleshooting − Incomplete Fusion

Incomplete Fusion − failure of weld metal to fuse completely with base metal or a preceeding weld bead.

	S-0637
Possible Causes	Corrective Actions
Workpiece dirty.	Remove all grease, oil, moisture, rust, paint, undercoating, and dirt from work surface before
	welding.
Insufficient heat input.	Set Metal Thickness Selector switch to a higher selection.
Improper welding technique.	Place stringer bead in proper location(s) at joint during welding.
	Adjust work angle or widen groove to access bottom during welding.
	Momentarily hold arc on groove side walls when using weaving technique.
	Keep arc on leading edge of weld puddle.
	Use correct gun angle of 0 to 15 degrees.

8-13. Troubleshooting − Burn-Through

Burn-Through − weld metal melting completely through base metal resulting in holes where no metal remains.

S-0640

Possible Causes	Corrective Actions
Excessive heat input.	Set Metal Thickness Selector switch to a lower selection.
	Increase and/or maintain steady travel speed.

OM-923 Page 32