Conduit Bending Terms: Take-Up, Gain, Shrink & More

Updated 2026-09-29

Measurements and numbers

Take-up (deduct): The amount subtracted from a stub height to find where the bender arrow goes for a 90°. It is cast into the shoe: 5" for 1/2" EMT, 6" for 3/4", 8" for 1", 11" for 1-1/4". More →
Gain: The conduit a bend saves compared with two straight legs meeting at a sharp corner. For a 90° on centerline radius R it is 2R − πR/2, about 0.43 × R; measured to the back of the 90, add one conduit diameter. Used when cutting a piece with 90s to length. More →
Shrink: How much shorter a run becomes because of an offset or saddle, since part of the conduit travels diagonally. At 30° it is about 1/4" per inch of offset depth; exactly depth × tan(θ ÷ 2). Added to the measurement when bending toward an obstruction. More →
Multiplier: The number that turns offset depth into the distance between bends: 10° = 6, 22.5° = 2.6, 30° = 2, 45° = 1.4, 60° = 1.2. It is the cosecant (1 ÷ sine) of the bend angle. More →
Depth (offset depth): How far an offset or saddle moves the conduit, measured square to the run.
Rise: The height a kick or stub must reach, measured square to the surface the conduit runs on. More →
Travel: The length of conduit between bend centers, or from a bend to where the rise is reached, measured along the pipe.
Run: The horizontal distance a bend covers, measured along the floor or wall rather than along the pipe.
Developed length: The length of conduit inside a bend (the arc). For a 90° on radius R it is π × R ÷ 2.
Centerline radius: The radius of a bend measured to the middle of the conduit. Hand-bender shoes are built to the NEC Chapter 9 Table 2 minimums: 4" for 1/2" EMT, 4-1/2" for 3/4", 5-3/4" for 1".
True offset: The actual depth of a rolling offset: √(horizontal² + vertical²). More →

Marks on the bender

Arrow: The main reference mark on a hand bender, used for stubs, offsets and kicks. For a stub-up the arrow goes on the mark with the hook facing the end.
Star point: A mark cast into the shoe that shows the back of a 90° when the bender is reversed. Used for back-to-back 90s without subtracting the take-up. More →
Rim notch (teardrop): The mark for the center of a bend, used for the center bend of a 3-point saddle. More →
Degree marks: Sight lines on the shoe at 10°, 22.5°, 30°, 45° and 60°. The bend has reached the angle when the conduit lines up with the mark.
Hook: The end of the shoe that grips the conduit. Its direction relative to the mark decides where the bend lands.

Bends

Stub-up (90° stub): A 90° bend that turns the conduit up out of a floor or wall to an exact height. More →
Offset: Two equal bends in opposite directions that move the run over an obstruction or off a surface and bring it back parallel. More →
Box offset: A shallow offset, about 1/2", that lets conduit enter a box or fitting flush with the surface. Usually two 10° bends, marks about 3" apart.
Kick: A single bend that angles the conduit away from a surface. More →
Kicked 90: A 90° stub with a small kick bent first so the stub stands off the wall.
3-point saddle: Three bends (a center bend and two at half its angle) that lift the conduit over a round obstruction such as a pipe. More →
4-point saddle: Two offsets, one up and one back down, with a flat top, used to clear a wide obstruction such as a duct. More →
Back-to-back 90s: Two 90s in one piece making a U, with an exact distance between the outsides (backs) of the two bends. More →
Rolling offset: An offset that moves the run over and up at the same time, bent in a plane rolled between horizontal and vertical. More →
Parallel offsets: The same offset bent in several conduits on a rack, with each conduit's marks moved spacing × tan(θ ÷ 2) so the runs stay evenly spaced.
Segmented bend (shots): A large-radius bend made from several small bends called shots. More →
Concentric bends: Nested 90s on a rack, each conduit on a radius larger than the one inside it by the center-to-center spacing.

Problems and technique

Dog-leg: An offset or kicked 90 whose bends are not in the same plane, so the conduit twists sideways. Caused by not rotating exactly 180° between bends.
Spring-back: The few degrees a bend relaxes when the handle is released. EMT springs back about 2°, so bend slightly past the angle.
Kink: A flattened or buckled bend. Kinked conduit reduces the internal diameter, which the NEC does not allow (for EMT, 358.24), and must be cut out.
Hickey: A tool for bending rigid conduit in place, and also a fitting used to hang fixtures.

Code and conduit

360° rule: The NEC limit of 360° of bends in total between pull points (for EMT, 358.26).
Conduit fill: The share of a raceway's internal area the conductors take up. NEC Chapter 9 allows 53% for one conductor, 31% for two and 40% for three or more. More →
Nipple: A raceway 24" or shorter between boxes or enclosures; it may be filled to 60%.
Box fill: The volume a box needs for its conductors, devices, clamps and grounds, per NEC 314.16. More →
EMT: Electrical metallic tubing: thin-wall steel conduit joined with set-screw or compression fittings, bent with hand benders.
RMC and IMC: Rigid metal conduit and intermediate metal conduit: threaded, thicker-walled steel conduit. On hand benders, the next EMT size up bends it (a 3/4" EMT shoe bends 1/2" rigid).
PVC: Rigid PVC conduit, Schedule 40 or 80. It is bent with heat (a hot box or heat blanket), not with a hand bender.