Conduit bending for apprentices: learn it, practice it, check it

What apprentices bend, and where it goes wrong

Most apprentices start on EMT with a hand bender: stub-ups out of boxes, offsets to clear a beam or step onto a box, 3-point saddles over a pipe, and kicks to bring a run off the wall. The bends are simple. So are the mistakes, and each one costs a stick of conduit.

• Adding the deduct instead of subtracting it. The stub comes out long by twice the deduct.
• Forgetting shrink. The offset lands short of where you measured.
• Spacing the marks for one angle and bending to another. The offset ends up the wrong height.
• Guessing the angle. Two bends a few degrees apart leave the conduit out of parallel.
• Rolling the conduit between bends. The second bend comes out of plane, and you have a dog leg.

The math, in four ideas

Gain is the fourth idea. A bend on a radius uses less conduit than the sharp corner on paper, so a 90 measured to its back, or a back-to-back 90, has to allow for it. Learn these four and every other bend is a combination of them.

Free practice on this site

Everything here is free and needs no account. The problems are worked out by the same engine as the app, with the multiplier method, so the answers match the textbook.

• Practice problems with answers: offsets, shrink and 90 marks, each answer hidden until you open it.
• The worksheet: a mixed set of offsets, saddles, 90s and kicks, so you practice choosing the method as well as the math.
• Journeyman exam prep: exam-style problems, the formulas to know cold and the traps that cost marks.
• The study guide: seven stages, from the parts of a bender to full runs with a cut length.
• The formulas page and the printable chart: every formula with a worked example, and the multipliers, deducts and conduit sizes on one page for your bag.
• Free calculators: offsets, saddles, kicks, stub-ups, rolling and parallel offsets and segmented 90s, to check your answers.

The app, on the phone you already have

BendMate runs in your phone’s browser, so there is nothing to install from an app store and no account to make. The free version works out offsets, 3- and 4-point saddles, 90s and kicks for any hand bender, or with the multiplier method, and includes the level, which reads a bend’s angle with the phone’s tilt sensor, and the bending tables. The bends most apprentices learn first are all in it.

• Pick the bender you were handed, and the marks come from its own radius and deduct.
• Switch to the multiplier method when you want the textbook numbers for class.
• A red or orange warning tells you when bends would overlap or leave too little straight for the shoe.
• It works offline once it has loaded, in a basement or a shop with no signal.
• The whole app and every guide are in Spanish as well as English, with the words used on job sites in the US and Mexico.

Pro is a one-time $5.99, with no subscription. It adds the rest of the 17 bend types, such as rolling and parallel offsets and compound and segmented 90s, mechanical, electric and hydraulic benders, several bends on one stick with the cut length, and the rack builder. You don’t need it to learn the basics.

A routine that works

1. Read the guide for one bend and work through its example.
2. Do five practice problems by hand.
3. Check them, then rework the ones you missed without looking.
4. Bend one on a scrap, measure it, and compare it with BendMate’s marks for your bender.
5. Write down each mistake and its cause, and redo those problems the next week.