Conduit 90-Degree Bend Take-Up Calculator

A conduit 90 bend take-up calculator determines the Bend mark from end for a stub-up. That mark is the layout point placed on the conduit before bending so the finished 90° stub reaches the intended height from its reference end.

Related tools: Stub-Up Bend Calculator, Box Offset Calculator, and Offset Bend Calculator.

For this worksheet, the output is used directly in conduit bending layout. It does not size conduit, evaluate raceway fill, calculate conductor ampacity, determine voltage drop, or select a branch-circuit or feeder conductor. Its purpose is limited to locating the bend mark using a take-up value already established for the bender and field reference being used.

Stub-Up Bend Mark

A stub-up is a 90° bend made near the end of a conduit to raise the raceway from a horizontal run, slab penetration, box approach, equipment connection, or similar reference point. The required finished dimension is the Desired stub height.

The bender does not form the center of the 90° bend exactly at the end of the finished stub. The bender’s geometry creates a take-up relationship that must be accounted for when locating the mark. In this mode, that relationship is entered directly rather than selected from a conduit-size table.

The calculator produces:

Result	Electrical layout use
Bend mark from end	Distance measured from the conduit reference end to the mark used for the 90° bend layout
Desired stub height	Finished target height entered for the stub-up
Entered take-up	Take-up value supplied from the selected bender or verified field reference

The completed mark should be measured from the same conduit end used to define the finished stub height. Changing the reference end, reversing the field convention, or using a different bender can change the required layout.

Take-Up Formula

The calculator applies the entered value using its local stub-up convention:

\(\displaystyle \text{Bend mark from end} = \text{Desired stub height} + \text{Entered take-up}\)

Where:

• Desired stub height is the finished stub dimension from the reference end, entered in inches.
• Entered take-up is the take-up value recorded for the bender, manufacturer, or established field layout reference.
• Bend mark from end is the resulting distance from the conduit end to the bend mark.

The calculator does not infer take-up from conduit trade size, EMT, IMC, RMC, PVC, bender shoe type, or manufacturer. Those conditions must be represented by the take-up value supplied in the input.

Calculation Example

For a finished stub height of 18 in and an entered take-up of 6 in:

\(\displaystyle \text{Bend mark from end} = 18\text{ in} + 6\text{ in} = 24\text{ in}\)

Field	Value
Desired stub height	18 in
Entered take-up	6 in
Take-up source reference	bender-record-a
Bend mark from end	24 in

Mark the conduit 24 in from the reference end under the same stub-up convention used to establish the 6 in take-up. The resulting 90° bend is intended to produce an 18 in finished stub height.

Take-Up Source Reference

The Take-up source reference records where the entered take-up came from, such as a specific bender record, manufacturer reference, shop standard, or verified field measurement. A label such as bender-record-a does not validate the take-up value; it preserves traceability between the layout calculation and the equipment or record used.

This is especially useful when several benders are present on a project or when conduit material, trade size, shoe geometry, or marking practices vary. Do not transfer a take-up value between benders without confirming that the local reference convention and actual field result match.

Field Verification

Verify the following before cutting or bending production conduit:

• Confirm the Desired stub height is measured from the intended finished reference end.
• Confirm the entered take-up belongs to the actual bender and conduit setup in use.
• Confirm whether the local bender reference treats take-up as an added or deducted layout value; the worksheet uses the stated addition convention.
• Confirm the conduit trade size, raceway material, bender shoe, and bending mark location agree with the take-up record.
• Make a test bend when the finished stub must align with equipment elevations, box entries, slab penetrations, rack elevations, or prefabricated assemblies.
• Account separately for couplings, connectors, offsets, kicks, parallel runs, cutting allowances, and field tolerances.

The result is a layout dimension based solely on the entered record: Bend mark from end = Desired stub height + Entered take-up. Final conduit installation still requires field verification of the bender, conduit size, sign convention, source reference, and actual bend markings.