Hobart Welding Products OM-240 438B manual Lack of Penetration Good Penetration, Metal remains

		Lack Of Penetration − shallow fusion between weld metal and base metal.
Lack of Penetration	Good Penetration
Possible Causes		Corrective Actions
Improper joint preparation.		Material too thick. Joint preparation and design must provide access to bottom of groove.
Improper weld technique.		Keep arc on leading edge of weld puddle.
Insufficient heat input.		Increase amperage. Select larger electrode and increase amperage.
		Reduce travel speed.
		Excessive Penetration − weld metal melting through base metal and hanging underneath weld.
	Good Penetration
Excessive Penetration
Possible Causes		Corrective Actions
Excessive heat input.		Select lower amperage. Use smaller electrode.
		Increase and/or maintain steady travel speed.
		Burn-Through− weld metal melting completely through base metal resulting in holes where no
		metal remains.

Possible Causes	Corrective Actions
Excessive heat input.	Select lower amperage. Use smaller electrode.
	Increase and/or maintain steady travel speed.
	Waviness Of Bead − weld metal that is not parallel and does not cover joint formed by base metal.

Possible Causes			Corrective Actions
Unsteady hand.			Use two hands. Practice technique.
			Distortion − contraction of weld metal during welding that forces base metal to move.
	Base metal moves
	in the direction of
		the weld bead.
Possible Causes			Corrective Actions
Excessive heat input.			Use restraint (clamp) to hold base metal in position.
			Make tack welds along joint before starting welding operation.
			Select lower amperage for electrode.
			Increase travel speed.
			Weld in small segments and allow cooling between welds.
			OM-240 438 Page 63