60 degree conduit offset: multiplier and shrink
By Andrew ·
Quick answer
The multiplier for a 60 degree offset is 1.155, which the trade rounds to 1.2. Shrink is 0.577" per inch of height, much more than the 1/2" the rule of thumb gives. A 10" offset at 60° puts the bends 11 9/16" apart and shrinks 5 3/4", where the rule says 5".
60° offset marks
| Offset height | Distance between bends | Shrink |
|---|---|---|
| 1" | 1 1/8" | 9/16" |
| 2" | 2 5/16" | 1 1/8" |
| 3" | 3 7/16" | 1 3/4" |
| 4" | 4 5/8" | 2 5/16" |
| 5" | 5 3/4" | 2 7/8" |
| 6" | 6 15/16" | 3 7/16" |
| 7" | 8 1/16" | 4 1/16" |
| 8" | 9 1/4" | 4 5/8" |
| 9" | 10 3/8" | 5 3/16" |
| 10" | 11 9/16" | 5 3/4" |
| 12" | 13 7/8" | 6 15/16" |
| 15" | 17 5/16" | 8 11/16" |
| 18" | 20 13/16" | 10 3/8" |
| 24" | 27 11/16" | 13 7/8" |
The steepest offset: when 60 degrees is worth it
At 1.155 the bends are barely further apart than the offset is tall: a 10" offset needs only 11 9/16". That makes 60° the answer for a tall offset that has to happen in very little length, such as coming around the edge of a beam or a duct that sits right at the box. It is rarely the first choice, because a steep angle is hard on the wire and costs the most shrink.
- Only where 45° still does not fit in the space.
- Tall offsets, from about 6" up. A small offset at 60° puts the two bends almost on top of each other.
- Where both bends have to finish within a few inches of a fixed point, such as a box or a coupling.
The shrink is large, and the rule is short
The exact shrink at 60° is 0.577" per inch, and the usual rule of 1/2" per inch is well under it. On a 10" offset the rule leaves you 3/4" short, enough to notice at the box. The multiplier rule of 1.2 errs the other way, a little long. Use the exact numbers for this angle.
| Offset height | Between bends at 45° | Between bends at 60° | Shrink at 45° | Shrink at 60° |
|---|---|---|---|---|
| 4" | 5 11/16" | 4 5/8" | 1 5/8" | 2 5/16" |
| 6" | 8 1/2" | 6 15/16" | 2 1/2" | 3 7/16" |
| 8" | 11 5/16" | 9 1/4" | 3 5/16" | 4 5/8" |
| 10" | 14 1/8" | 11 9/16" | 4 1/8" | 5 3/4" |
| 12" | 17" | 13 7/8" | 4 15/16" | 6 15/16" |
Bending it on a hand bender
Most hand benders put a 60° line or center-of-bend notch toward the heel of the head, so you pull the handle a long way. The bend takes more effort than a 30° bend, and the two bends need straight conduit between them to grip. If the arcs would run into each other, the offset is too small for 60° and you need a shallower angle.
- Check the offset is tall enough for 60°: a short offset puts the bends so close together that the bender has nothing to hold on the second one.
- Mark both bends with the exact spacing and the exact shrink.
- Bend the first mark to 60°, roll half a turn, and bend the second to match. Check the legs are parallel.
The NEC allows 360° of bends between pull points, and a 60° offset uses 120° of it. Three of them use the whole allowance.
Get the marks for your bender
BendMate works this out from your bender’s radius and deduct, flags a bend that won’t work, and shows you every mark.
Common questions
What is the multiplier for a 60 degree offset?
1.155, usually rounded to 1.2. An 8" offset needs 9 1/4" between the bends.
How much does a 60 degree offset shrink?
0.577" per inch of height, so a 10" offset shrinks 5 3/4". The 1/2" rule of thumb undershoots it.
Is a 60 degree offset too steep?
It is the steepest standard angle: hard on wire pulls, heavy on shrink, and a poor fit for small offsets. Use it only when 45° will not fit in the space.