Miller Electric Bobcat 250 Owner's Manual page 66

14-19. Troubleshooting − Burn-Through
Possible Causes
Excessive heat input.
14-20. Troubleshooting − Waviness Of Bead
Possible Causes
Unsteady hand.
14-21. Troubleshooting − Distortion
Possible Causes
Excessive heat input.
OM-4419 Page 62
Burn-Through − weld metal melting completely through base metal resulting
in holes where no metal remains.
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.
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.
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.
Corrective Actions
Corrective Actions
Corrective Actions