How to Fix a Dog Leg in a Conduit Bend

What a dog leg is

The two bends of an offset, the three of a saddle and the two of a back-to-back 90 should all lie in one flat plane. Lay a good offset on its side on the floor and every part of it touches. When one bend is turned a few degrees out of that plane, the conduit has a dog leg (or dogleg): the end past it points slightly sideways, so it misses the box, sits off the wall, or will not line up with the straps.

What causes it

• Rolling the wrong amount. The second bend of an offset is made with the conduit turned exactly half a turn from the first. A little more or a little less throws the second bend out of plane.
• The conduit turning in the shoe. If it is not fully seated, or the pull is jerky, it can roll in the groove as it bends.
• Pulling the handle off to one side. The bend follows the handle. Leaning it sideways twists the conduit.
• No reference line. Without a line along the top, a few degrees of roll are hard to see until the bend is made.

How to spot one

1. Sight down it. Hold one end up to your eye and look along the conduit. The bends should stack up in one line. If the far leg swings off to one side, it is out of plane.
2. Lay it on the floor. Put the bent conduit on its side on a flat floor. All of it should touch. If one end lifts or the conduit rocks, the bend nearest that end is out of plane.
3. Follow your line. A pencil line drawn along the top before bending should stay in the plane of the bends all the way along. If it drifts round to one side, the conduit rolled.
4. Check before you install. Once the conduit is strapped, a dog leg is much harder to correct.

Fixing a slight dog leg

If the conduit is only a few degrees out and is not kinked or flattened, you can usually twist it back. Hold one leg still, under your foot or in the bender, take hold of the other leg, and turn it a little at a time toward the plane of the first bend. Lay it on the floor after each try.

When to cut it and bend again

• The conduit is kinked, creased or flattened anywhere. A damaged section is weak, so cut it out rather than straighten it.
• It is more than slightly out of plane, or a couple of careful twists have not brought it back.
• The offset has to land on an exact dimension and the correction has moved it.

If there is enough conduit left, cut off the bad bends and lay the offset out again on the rest. Otherwise start a new piece. It is quicker than fighting a dog leg into a box.

How to avoid the next one

1. Before the first bend, draw a straight line along the top of the conduit through every mark.
2. After the first bend, roll the conduit exactly half a turn, so the line comes round to the opposite side.
3. Before the second pull, sight along the conduit: the first bend should sit in line with the bender’s handle, not off to one side.
4. Keep your weight on the heel and pull the handle straight, in line with the conduit.
5. Lay the conduit on the floor after the second bend, before you do anything else with it.