Miller Bobcat 225 Owner's Manual page 68

12-11. Welding T-Joints
1-3. Welding T-Joints
3
1-3. Welding T-Joints
1-4. Weld Test
2 3 in.
(51-76 mm)
12-12. Weld Test
2
1/4 in.
(6.4 mm)
1-4. Weld Test
2 3 in.
(51-76 mm)
1/4 in.
(6.4 mm)
12-13. Troubleshooting
Possible Causes
Arc length too long.
Damp electrode.
Workpiece dirty.
OM-286503 Page 64
3
30
1/16 in.
(1.6 mm)
1
45
2
2
3
1
2
45 (51-76 mm)
2
2
2
1
3
2 3 in.
(51-76 mm)
2
2
1
Porosity - small cavities or holes resulting from gas pockets in weld metal.
Reduce arc length.
Use dry electrode.
Remove all grease, oil, moisture, rust, paint, coatings, slag, and dirt from work surface before
welding.
4
4
3
3
3 in.
3
1
3
1
Corrective Actions
1 Electrode
2 Fillet Weld
1
Keep arc short and move at definite rate of
speed. Hold electrode as shown to provide
fusion into the corner. Square edge of the
weld surface.
For maximum strength weld both sides of up-
right section.
3 Multi-Layer Deposits
Weld a second layer when a heavier fillet is
needed. Use any of the weaving patterns
shown in Section 12-8. Remove slag before
1
making another weld pass.
1 Vise
2 Weld Joint
3 Hammer
Strike the weld joint in the direction shown. A
good weld bends over but does not break.
If the weld breaks, examine it to determine
the cause.
If the weld is porous (many holes), the arc
length was probably too long.
If the weld contains bits of slag, the arc may
have been too long or the electrode was
moved incorrectly which allowed molten slag
to be trapped in the weld. This may happen
on a V-groove joint made in several layers
and calls for additional cleaning between
layers.
If the original beveled surface is visible the
material was not fully melted which is often
caused by insufficient heat or too fast a trav-
el speed.