How to Measure the Angle of a Conduit Bend

Measure from the straight part

A bend’s angle is how far the bent leg turns away from the straight part of the conduit. If you read the bent leg against the floor and the floor slopes, the slope ends up in the reading. Reading both parts and taking one from the other, or zeroing on the straight part, takes it out.

The tools, and what each is good for

• The bender’s angle lines. Most hand bender heads have angle lines cast on the side. Sight the conduit against them as you pull. They get you close, but the reading depends on where your eye is, and they show the angle under load, before springback.
• A torpedo level. Plumb on the stub means a 90. Many torpedo levels also have a 45° vial. Both assume the straight part is level, so check that too.
• An angle finder or protractor. A magnetic angle finder holds itself on steel conduit. A two-arm protractor reads the angle between the legs, so take it from 180°. A digital angle gauge with a zero button works like a phone level.
• A phone level. BendMate’s level, part of the free version, reads the tilt sensor in a phone or tablet. Zero it on the straight part, lay it on the bent leg, and it shows the bend’s angle. The floor does not have to be level.

Using a phone level

1. Open the level and start it. If the browser asks for motion access, allow it.
2. Lay the phone lengthwise along the straight part of the conduit, screen up or standing on its edge, and keep it still. It zeroes itself there, or you can zero it by hand.
3. Lay it along the bent leg the same way. The reading is the bend’s angle.
4. For the next bend, zero it on a straight part again.

Springback: check after you let off

Conduit springs back a little when you ease off the handle, so the angle you see while pulling is not quite the one you end up with. Go slightly past, let off, measure, and pull a little more if it is still under. Rigid springs back more than EMT. Bend a scrap at the job’s angle first to learn how far past to go.

A couple of degrees matters. The height of an offset is the distance between its bends × sin(angle), so two bends that come out short leave the offset short.

Checking a 90

1. Hold a torpedo level against the face of the stub. The bubble should read plumb.
2. Move it to the side of the stub and check again. A stub that is plumb one way but not the other is leaning, often because the conduit twisted in the shoe.
3. If the floor is not level, zero a phone level on the long leg instead, and read the stub: it should show 90°.
4. Measure the stub to the back of the bend while you are there.

For an offset, check that both bends read the same. For a 3-point saddle, the center bend should read twice each outer bend.