90° Stub-Up Calculator — Take-Up Marks for Hand Benders
Who this is for: For apprentices nailing their first panel stubs and journeymen who want the mark confirmed before bending the last stick of the day — no chart, no scrap, no second bend.
Not the right tool for: Back-to-back legs and kicks off a fixed point — the star-mark method has its own measuring flow · Segmented (shot) bends on large rigid — developed-length math, not take-up
Enter the stub height and conduit size — get the take-up, the exact mark from the end of the conduit, and the full take-up table.
Quick answer: Stub mark = rise + take-up, measured from the end of the conduit: 1/2" take-up is 5", 3/4" is 8", 1" is 11", 1-1/4" is 14". A 25" stub on 1/2" EMT marks at 30"; a 30" mark gives a 25" rise (30 − 5). Line the bender's arrow up on the mark and bend.
Finished height, deck to back of the 90°.
| Take-up table — mark for a 25" rise | 1/2" | 3/4" | 1" | 1-1/4" |
|---|---|---|---|---|
| Take-up / mark from end | 5″ → 30″ | 8″ → 33″ | 11″ → 36″ | 14″ → 39″ |
| Formula | mark from end = rise + take-up |
|---|---|
| Take-up | 1/2" = 5" · 3/4" = 8" · 1" = 11" · 1-1/4" = 14" |
| Example | 25" rise on 1/2" EMT → mark at 30" |
| Reverse | 30" mark → 25" rise (30 − 5) |
| Reference mark | Arrow (star is for back-to-back legs) |
| Status | Hand-bender teaching reference (Benfield take-ups, multipliers and shrink), compiled September 2026. Brand shoes vary — the chart stamped on your bender wins. Factory elbows, hydraulic and mechanical bender work are different methods. |
How does the stub-up mark work?
A 90° bend consumes conduit — the arc from the start of the bend to the back of the stub. That consumption is the take-up, and the teaching-standard values are 5" for 1/2", 8" for 3/4", 11" for 1" and 14" for 1-1/4". The mark goes at rise + take-up, measured from the end of the conduit: a 25" stub on 1/2" EMT marks at 30" (25 + 5). After the bend, the finished height is the mark minus take-up — a 30" mark lands a 25" rise (30 − 5). Measure from the end of the conduit, line up the bender's arrow on the mark, and pull the bend in one smooth motion, keeping the conduit flat on the ground so the stub rises vertically. If you know the mark (say the stub must fit in 30" of wall space), the calculator reads backwards too: rise = mark − take-up.
Common uses
- Bending stub-ups to land on a panel or box knockout at a set height
- Cutting stub stock to exact length before bending — no wasted inches
- Checking an apprentice's marks before the scrap bin gets them
- Working backwards from a fixed wall space to the achievable rise
Keeping the stub square
The math puts the mark in the right place; technique keeps the stub vertical. Anchor the conduit foot on the ground, keep the conduit level in the bender saddle, and pull the handle in one smooth stroke until the shoe reads 90° — eyeball the rise against a level or the wall. Two common failures: bending off-plane because the conduit twisted in the saddle (the stub leans), and overbending past 90° because the last inch of pull comes fast. Most benders slightly over-travel at the stop; many electricians bend stubs a hair past 90° deliberately and let the conduit's own springback settle it square — check your shoe's behavior once on scrap and you'll know its habit.