Conduit Offset Bend
45° Conduit Offset
Everything for a 45 degree offset: the multiplier, the shrink, a worked example, and the calculator, all from the same math your bender uses.
The 45° Offset Numbers
| Multiplier (bender chart, applied / exact 1/sin) | 1.4 / 1.41 |
| Shrink per inch of offset | 3/8″ (0.3750″) |
| 6″ offset: distance between bends | 8.4″ |
| 6″ offset: shrink to subtract | 2.25″ |
Distance between bends = offset depth × 1.4. Shrink = offset depth × 3/8″. Both bends are 45 degrees, rotated 180° apart. Bender charts print 1.4 at 45°, which the calculator applies; exact 1/sin is 1.41. The chart value is what the calculator applies, so its marks match the table on your bender (see the offset multiplier chart).
The Geometry of a 45° Bend
A 45 degree offset is two 45 degree bends. On a standard 3/4" EMT bender the centerline radius is 4.5″, so each 45 degree bend has a developed length of 3.53″ of conduit through the curve (developed length = radius × the angle in radians). That is the exact geometry the 3D renderer draws for this bend. For the developed length at every size and angle, see the bend radius and developed length reference.
Calculate Your 45° Offset
The calculator opens on the worked example, a 6″ offset at 45°. Enter your own offset depth for its mark spacing and shrink.
Frequently Asked Questions
What is the multiplier for a 45 degree offset?
The multiplier for a 45 degree offset is 1.4, the constant bender-manufacturer charts print, and it is what this calculator applies. It is the rounded cosecant: exact 1/sin(45 degrees) is 1.41. Multiply your offset depth by the multiplier to get the distance between the two bend marks. For a 6 inch offset that is 6 x 1.4 = 8.4 inches between marks.
How much does a 45 degree offset shrink?
A 45 degree offset shrinks 3/8 inch for every inch of offset depth. So a 6 inch offset shrinks the run about 2.25 inches, and a 4 inch offset shrinks about 1.5 inches. Subtract the shrink from your measurement so the conduit ends and fittings still land where you need them.
How do you bend a 45 degree offset?
Mark the first bend where the offset should start, then measure 8.4 inches (for a 6 inch offset) toward the free end and mark the second bend. Bend both marks to 45 degrees, keeping the bends in the same plane and rotating the conduit 180 degrees between them so the offset lies flat. Check the depth against your target and subtract the 2.25 inch shrink when you cut or measure the run.
When should I use a 45 degree offset?
A 45 degree offset is a tight offset for close obstacles. Its high angle keeps the bends close together (multiplier 1.4) so it fits small spaces, but it shrinks more (3/8 inch per inch) and is a harder wire pull. Use it when you must step over something in a short distance.