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Bending on centers

There are two ways to mark a bend. You can mark where the bender’s arrow goes (the deduct way), or where the middle of the bend will be. Done right, both give the same bend in the same place; they line up with different points on the shoe. Choose in Settings under Place marks on: Arrow (deduct) or Bend center.

Marking for the arrow

The mark lines up with the arrow, and the bend forms on the side away from the hook, starting a short way past the arrow (the Start of bend in Bender Specs, 7/16" on the 1/2" EMT hand bender). So the hook direction matters: turn the bender round and the same mark puts the bend somewhere else. The marks list says which way each hook faces (Hook toward end or Hook away from end). A 90 is always marked for the arrow, whatever the setting, because its deduct is measured to it.

Marking the bend center

The mark is the middle of the bend’s arc. Line it up with the shoe’s center mark for that angle (Line up with bend center), or with the center notch when the angle is the one the notch is cut for (Line up with center notch). The bend forms evenly on both sides of the mark, so the hook direction doesn’t change where it lands. It suits work measured to bend centers, like matching a neighbor’s bends.

The same 6" offset at 30°, finished 40" from the end, on the 1/2" EMT hand bender
Offset height
6"
Angle
30°
Distance to obstruction
40"
Marks for the arrow
26 7/8" and 38 7/8"
Marks on bend centers
28 7/16" and 40 7/16"
Difference
1 9/16", the 30° shoe center mark

Shoe center marks

Most shoes have at most one center mark, so the calculator works out where the others would be. Bender Specs lists them under Shoe center marks, measured from a reference line at the arrow, along the side away from the hook. To put them on your shoe:

  1. Put a straight scrap of conduit in the bender and draw a line on it at the arrow.
  2. Measure from that line, away from the hook, to each distance in the list and mark the conduit.
  3. Carry each mark straight across onto the side of the shoe with a paint pen or scribe, and label it with its angle.
center mark = start of bend + R × angle/2
Half the bend’s arc length past the start of the bend, with the angle in radians.
Shoe center marks for the 1/2" EMT hand bender (4 3/16" radius, 5" deduct)
Measured from
a line at the arrow
Start of bend
7/16"
15°
1"
22.5°
1 5/16"
30°
1 9/16"
45°
2 1/8"
60°
2 5/8"

Flipping a mark

In Multiple Bends every bend starts with the hook facing the conduit end. Flip turns a bend round so the hook faces the other way, for when the bender has to go on from the other side. A mark for the arrow then moves forward by the bend’s arc length plus twice the start of bend, so it sits as far past the bend’s center as it sat before it: 3 1/8" for a 30° bend on the 1/2" EMT hand bender. A center mark doesn’t move when flipped.

The three-point saddle’s center notch

On the Three-point saddle screen the center bend is marked at its center in both modes and lined up with the center notch, because that is how the center bend is made on a hand bender. In arrow mode only the two outer bends go on the arrow. The notch is usually cut for 45°, which suits 22.5° outer bends. With 30° outer bends the center is 60°, and its mark says Line up with bend center: use the 60° shoe center mark instead. In Multiple Bends the saddle’s center bend is marked like every other bend.