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Bend It Like a Pro!

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dquintiliani

Tier 1
For Schools

Lesson Plan

Bend It Like a Pro! Lesson Plan

Students will be able to identify common EMT conduit bends, understand basic bending calculations, and apply these concepts to solve practical problems related to conduit installation.

Mastering EMT conduit bending is a foundational skill for anyone entering the electrical trades. This lesson provides essential knowledge that directly translates to real-world job readiness and safety in electrical installations.

Audience

11th Grade

Time

30 minutes

Approach

Direct instruction, visual aids, interactive questioning, and practical application problems.

Materials

Bend It Like a Pro! Slide Deck, EMT Bending Warm-Up, EMT Bending Practice Worksheet, EMT Bending Answer Key, and EMT Bending Cool-Down

Prep

Teacher Preparation

15 minutes

  • Review the Bend It Like a Pro! Slide Deck for content and flow.
    - Print copies of the EMT Bending Warm-Up for each student.
    - Print copies of the EMT Bending Practice Worksheet for each student.
    - Review the EMT Bending Answer Key to ensure understanding.
    - Prepare to project the Bend It Like a Pro! Slide Deck.
    - Gather a piece of actual EMT conduit (if available) and a hand bender for demonstration purposes (optional).
    - Familiarize yourself with the Teacher Script.
    - Print copies of the EMT Bending Cool-Down for each student.

Step 1

Warm-Up: What's Your Angle?

5 minutes

  • Distribute the EMT Bending Warm-Up.
    - Instruct students to complete the warm-up independently.
    - Briefly discuss student responses, connecting them to prior knowledge or everyday observations of angles and bends.

Step 2

Introduction to EMT Bending

10 minutes

  • Use the Bend It Like a Pro! Slide Deck to introduce EMT conduit and the importance of precise bending.
    - Explain common bends: 90-degree bend, offset bend, and saddle bend.
    - Demonstrate (or visually explain using slides/diagrams) the basic principles of using a hand bender, including the star/arrow, hook, and degree marks.
    - Highlight key terms: 'take-up,' 'stub-up,' 'gain,' and 'shrinkage.'
    - Refer to the Teacher Script for guiding questions and talking points.

Step 3

Bending Calculations Practice

10 minutes

  • Distribute the EMT Bending Practice Worksheet.
    - Guide students through the first few problems on the worksheet, focusing on 90-degree and offset bend calculations.
    - Encourage students to work collaboratively or in small groups to solve the problems.
    - Circulate the room to provide support and answer questions.
    - Use the EMT Bending Answer Key as a reference.

Step 4

Cool-Down: Quick Check

5 minutes

  • Distribute the EMT Bending Cool-Down.
    - Students should independently complete the cool-down.
    - Collect cool-downs to assess student understanding and inform future instruction.
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Slide Deck

Bend It Like a Pro!

The Art of Conduit Bending

Why is bending conduit important?

  • Safety First! Proper bending protects wires.
  • Looks Professional! Neat installations are a sign of a skilled electrician.
  • Efficiency! Reduces the need for costly and time-consuming fittings.
  • Real-world skill! A key trade skill for electricians.

Welcome students and introduce the exciting topic of EMT conduit bending! Briefly explain why this skill is vital in electrical work. Connect to prior knowledge or everyday observations of pipes and wires.

What Kind of Bends Do We Need?

Common EMT Conduit Bends

  1. 90-Degree Bend: The most fundamental bend, creating a right angle.
  2. Offset Bend: Used to navigate around obstacles or change elevation.
  3. Saddle Bend: Used to go over a large obstruction, like another pipe or beam. (We'll focus on 90s and offsets today!)

Introduce the main types of bends students will encounter. Briefly describe each one and perhaps ask students if they've seen these shapes in real life.

Meet Your Bender: Key Parts

The Hand Bender

  • Hook: Secures the conduit during the bend.
  • Foot Pedal/Foot Correcter: Provides leverage.
  • Arrow/Star: Alignment mark for bending.
  • Degree Marks: Used to measure angles (e.g., 10°, 22.5°, 30°, 45°).
  • Stub-Up/Take-Up Mark: Indicates the distance from the shoe to the bending point.

Explain the essential parts of a hand bender and their functions. Emphasize that knowing these parts is crucial for successful bending. You can physically show a bender if you have one.

The Mighty 90-Degree Bend

The Basics of a 90

  • Goal: Make a perfect right angle (90 degrees).
  • Key Concept: Take-Up (or Stub-Up): This is the distance from the end of the conduit to the bending mark.
    • Every bender has a specific take-up value (e.g., 5 inches for 1/2" EMT bender).
  • Formula: Desired Stub-Up - Take-Up = Mark on Conduit

Example: If you want a 10-inch stub-up and your bender has a 5-inch take-up, where do you mark?

Focus on the 90-degree bend. Explain the concept of 'take-up' or 'stub-up' and how it's measured. Provide a simple example.

Offset Bends: Going Around Obstacles

Navigating Around Things

  • Purpose: To move the conduit around an obstruction while keeping it parallel to the surface.
  • Two Bends, Same Direction: An offset uses two equal bends.
  • Key Concept: Shrinkage: When you bend conduit, it gets shorter. Offsets cause shrinkage!
  • Calculating Shrinkage: Requires a bit more math, often using multipliers based on the angle (e.g., 30-degree bend = 1/4" shrinkage per inch of offset).

Introduce offset bends and their purpose. Explain the 'shrinkage' concept simply. The formula can be introduced, but the focus should be on the practical application and understanding why it's needed.

Saddle Bends: Going Over Large Objects

Smoothly Crossing Barriers

  • Purpose: To smoothly go over a larger obstruction, like another pipe.
  • Three Bends: A saddle bend consists of a center bend and two smaller 'kick' bends on either side.
  • Complex Calculations: Involves more advanced math to account for gain and shrinkage across multiple bends.
  • Today's Focus: We will primarily focus on 90-degree and offset bends to build our foundation.

Briefly mention saddle bends for context, but reiterate that the main focus for today is 90s and offsets due to time constraints.

Time to Practice!

Apply Your Knowledge

  • You'll now receive a worksheet with practice problems.
  • Work through the 90-degree and offset bend calculations.
  • Don't be afraid to ask questions or work with a partner!
  • Remember: Accuracy is key in electrical work!

Transition to the worksheet and encourage students to apply what they've learned. Remind them that practice is key.

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Script

EMT Bending: Teacher Script

Warm-Up: What's Your Angle? (5 minutes)

(Teacher says): "Good morning/afternoon, everyone! To get our brains warmed up, I've handed out a quick EMT Bending Warm-Up. Take about 3 minutes to complete it quietly on your own. Think about angles you see around you every day and how things are bent or shaped to fit."

(Pause for students to complete warm-up)

(Teacher says): "Alright, let's briefly chat about what you noticed. Who can share an example of an angle or a bend they identified? Why do you think it was shaped that way?"

(Facilitate a brief discussion, connecting student responses to the idea of needing to route things effectively.)

Introduction to EMT Bending (10 minutes)

(Teacher says): "Great job! Today, we're diving into a super important skill for anyone interested in electrical work: EMT Conduit Bending. As electricians, you'll often need to run electrical wires through metal tubes called EMT conduit to protect them and ensure a safe, organized installation. But buildings aren't always straight lines, are they? That's why we need to bend this conduit precisely."

(Advance to Slide 1: Bend It Like a Pro!)

(Teacher says): "Take a look at our first slide, 'Bend It Like a Pro!' The goal here is to understand why accurate bending is so critical. Think about it: if the conduit isn't bent correctly, what problems could that cause?"

(Allow 1-2 student responses. Guide them toward safety and efficiency.)

(Teacher says): "Exactly! Poor bends can damage wires, make the job look messy, and even cause dangerous electrical issues. But with the right skills, you'll be bending conduit like a pro, making installations safe, professional, and efficient. This is a real-world skill that employers value!"

(Advance to Slide 2: What Kind of Bends Do We Need?)

(Teacher says): "There are a few common types of bends you'll use. Today, we'll focus on the basics: the 90-degree bend which makes a perfect corner, and the offset bend, which helps us go around obstacles. We'll briefly mention the saddle bend for larger obstructions, but our main focus will be on the first two."

(Advance to Slide 3: Meet Your Bender: Key Parts)

(Teacher says): "To make these bends, we use a tool called a hand bender. It might look simple, but each part plays a crucial role. Pointing to the screen... This is the hook, which holds the conduit. The foot pedal gives us leverage. And these marks here – the arrow or star and the degree marks – are essential for measuring our bends accurately. The stub-up/take-up mark tells us where our bend will start relative to the bender shoe."

(If you have a physical bender, demonstrate holding it and pointing out the parts.)

(Advance to Slide 4: The Mighty 90-Degree Bend)

(Teacher says): "Let's start with the most common bend: the 90-degree bend. Imagine you need to run conduit up a wall and then turn it to go across the ceiling. That's a 90-degree bend. The key concept here is take-up or stub-up. This is the measurement from the very end of your conduit to where the bend will begin, ensuring you get the exact height you need."

(Teacher says): "Every bender has a specific 'take-up' value. For a typical 1/2-inch EMT bender, it's usually around 5 inches. This means the bend will start 5 inches from the hook. So, if you want a 10-inch stub-up (the finished height of the bent conduit), you would mark your conduit at 5 inches from the end. Why do you think that is?"

(Allow students to think/respond. Guide them to understand the bender itself takes up space.)

(Teacher says): "Exactly! The bender itself accounts for some of that length. The simple formula is: Desired Stub-Up - Bender Take-Up = Mark on Conduit. So for our 10-inch stub-up with a 5-inch take-up bender, you'd mark your conduit at 5 inches from the end, place that mark at the arrow on your bender, and make your bend."

(Advance to Slide 5: Offset Bends: Going Around Obstacles)

(Teacher says): "Next, we have offset bends. These are used when you need to run conduit along a wall, but there's something sticking out – maybe another pipe or a structural beam – that you need to get around. An offset essentially creates two gentle bends in the same direction to move the conduit out and then back in, keeping it parallel to the surface."

(Teacher says): "A crucial thing to remember with offsets is shrinkage. When you bend conduit, it actually gets a little shorter. So, we have to account for that in our measurements. For example, if you use two 30-degree bends to make an offset, the conduit will shrink by a certain amount, and you need to know how to calculate that to ensure your conduit run ends up the correct length."

(Advance to [Slide 6: Saddle Bends: Going Over Large Objects](#bend-it-like a-pro-slide-deck))

(Teacher says): "Finally, very briefly, saddle bends are used for larger obstructions. They involve three bends: a center bend and two smaller bends on either side, creating a smooth arc over an object. The calculations for these are a bit more complex, and we won't dive deep into them today, but it's good to know they exist for when you encounter bigger obstacles."

Bending Calculations Practice (10 minutes)

(Advance to Slide 7: Time to Practice!)

(Teacher says): "Now it's your turn to apply what we've learned! I'm handing out the EMT Bending Practice Worksheet. We'll focus on the 90-degree and offset bend calculations. I want you to work through these problems. Feel free to collaborate with a partner, but make sure everyone understands the process. I'll be circulating to answer any questions you have."

(Distribute worksheets. Circulate, provide support, and use the EMT Bending Answer Key as a reference for guiding students.)

Cool-Down: Quick Check (5 minutes)

(Teacher says): "Excellent work today, electricians! To wrap up, please complete this quick EMT Bending Cool-Down before you leave. It will help me see what you've understood and what we might need to review. Hand them to me as you finish up."

(Collect cool-downs.)

(Teacher says): "Great job today, everyone! Keep thinking about those angles and bends you see around you. See you next time!"

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Warm Up

EMT Bending Warm-Up: What's Your Angle?

Instructions: Think about your everyday environment. Look around the classroom, or imagine parts of a building or a park. Answer the questions below.

  1. Can you identify three different objects or structures that have a bend or an angle in them? Describe them and the type of bend/angle you see.










  2. Why do you think these objects were designed or built with a bend or angle instead of being perfectly straight? What purpose does the bend serve?






  3. Imagine you are trying to run a cable from one point to another, but there is an obstacle in the way. What might you have to do to the cable (or the pipe holding the cable) to get it past the obstacle?






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Worksheet

EMT Bending Practice Worksheet

Instructions: Read each problem carefully and use the information provided to calculate the necessary measurements for bending EMT conduit. Assume you are using a 1/2-inch EMT hand bender with a take-up of 5 inches for 90-degree bends.

Part 1: 90-Degree Bends (Stub-Ups)

For a 90-degree bend, use the formula: Mark on Conduit = Desired Stub-Up - Bender Take-Up

  1. You need to create a 90-degree bend with a finished stub-up height of 8 inches. Where should you place your mark on the conduit before bending?



  2. An electrical box is mounted on a wall, and you need to run conduit from the floor to the bottom of the box. The bottom of the box is 15 inches from the floor. Where do you mark the conduit for your 90-degree bend?



  3. You have a piece of conduit and want to create a stub-up that is 12 inches tall. What measurement should you mark on the conduit?



Part 2: Offset Bends

For offset bends, we need to consider the depth of the offset and the angle of the bends. For these problems, use the following multipliers and shrinkage values:

  • 30-degree bends: Multiplier = 2, Shrinkage = 1/4 inch per inch of offset depth
  • 45-degree bends: Multiplier = 1.414, Shrinkage = 3/16 inch per inch of offset depth

Offset Formula:

  • Distance Between Marks (DBM): Offset Depth x Multiplier
  • Total Shrinkage: Offset Depth x Shrinkage Rate

  1. You need to create an offset to go around an obstacle that is 2 inches deep. You decide to use two 30-degree bends.

    • What is the Distance Between Marks (DBM) you should measure on the conduit?



    • What is the total shrinkage for this offset?



  2. You encounter a shallower obstruction, 1.5 inches deep, and choose to use two 45-degree bends.

    • What is the Distance Between Marks (DBM) you should measure on the conduit?



    • What is the total shrinkage for this offset?



  3. Challenge Question: You need an offset to clear a 3-inch deep obstacle. If you use 30-degree bends, what will be your DBM and total shrinkage? If you use 45-degree bends, what will be your DBM and total shrinkage? Which option results in less shrinkage?

    • 30-degree bends:
      • DBM:
      • Shrinkage:


    • 45-degree bends:
      • DBM:
      • Shrinkage:


    • Which option has less shrinkage and why might that be important?






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Answer Key

EMT Bending Practice Worksheet: Answer Key

Part 1: 90-Degree Bends (Stub-Ups)

Assume 1/2-inch EMT hand bender with a take-up of 5 inches.

Formula: Mark on Conduit = Desired Stub-Up - Bender Take-Up

  1. You need to create a 90-degree bend with a finished stub-up height of 8 inches. Where should you place your mark on the conduit before bending?

    • Thought Process: The desired stub-up is 8 inches. The bender has a take-up of 5 inches. To find where to mark, subtract the take-up from the desired stub-up.
    • Calculation: 8 inches - 5 inches = 3 inches
    • Answer: Mark the conduit at 3 inches from the end.

  2. An electrical box is mounted on a wall, and you need to run conduit from the floor to the bottom of the box. The bottom of the box is 15 inches from the floor. Where do you mark the conduit for your 90-degree bend?

    • Thought Process: The desired stub-up height is the distance to the bottom of the box, which is 15 inches. Use the bender take-up of 5 inches.
    • Calculation: 15 inches - 5 inches = 10 inches
    • Answer: Mark the conduit at 10 inches from the end.

  3. You have a piece of conduit and want to create a stub-up that is 12 inches tall. What measurement should you mark on the conduit?

    • Thought Process: The desired stub-up is 12 inches. The bender take-up is 5 inches.
    • Calculation: 12 inches - 5 inches = 7 inches
    • Answer: Mark the conduit at 7 inches from the end.

Part 2: Offset Bends

Multipliers and Shrinkage Values:

  • 30-degree bends: Multiplier = 2, Shrinkage = 1/4 inch per inch of offset depth
  • 45-degree bends: Multiplier = 1.414, Shrinkage = 3/16 inch per inch of offset depth

Offset Formulas:

  • Distance Between Marks (DBM): Offset Depth x Multiplier
  • Total Shrinkage: Offset Depth x Shrinkage Rate

  1. You need to create an offset to go around an obstacle that is 2 inches deep. You decide to use two 30-degree bends.

    • What is the Distance Between Marks (DBM) you should measure on the conduit?
      • Thought Process: Offset depth is 2 inches. Multiplier for 30-degree bends is 2.
      • Calculation (DBM): 2 inches x 2 = 4 inches
      • Answer (DBM): 4 inches
    • What is the total shrinkage for this offset?
      • Thought Process: Offset depth is 2 inches. Shrinkage rate for 30-degree bends is 1/4 inch per inch.
      • Calculation (Shrinkage): 2 inches x 0.25 inches/inch = 0.5 inches
      • Answer (Shrinkage): 0.5 inches (or 1/2 inch)

  2. You encounter a shallower obstruction, 1.5 inches deep, and choose to use two 45-degree bends.

    • What is the Distance Between Marks (DBM) you should measure on the conduit?
      • Thought Process: Offset depth is 1.5 inches. Multiplier for 45-degree bends is 1.414.
      • Calculation (DBM): 1.5 inches x 1.414 = 2.121 inches
      • Answer (DBM): Approximately 2.12 inches
    • What is the total shrinkage for this offset?
      • Thought Process: Offset depth is 1.5 inches. Shrinkage rate for 45-degree bends is 3/16 inch per inch.
      • Calculation (Shrinkage): 1.5 inches x (3/16) inches/inch = 1.5 x 0.1875 = 0.28125 inches
      • Answer (Shrinkage): Approximately 0.28 inches (or 9/32 inch)

  3. Challenge Question: You need an offset to clear a 3-inch deep obstacle. If you use 30-degree bends, what will be your DBM and total shrinkage? If you use 45-degree bends, what will be your DBM and total shrinkage? Which option results in less shrinkage?

    • 30-degree bends:
      • Thought Process (DBM): Offset depth = 3 inches. Multiplier = 2.
      • Calculation (DBM): 3 inches x 2 = 6 inches
      • Answer (DBM): 6 inches
      • Thought Process (Shrinkage): Offset depth = 3 inches. Shrinkage rate = 1/4 inch per inch.
      • Calculation (Shrinkage): 3 inches x 0.25 inches/inch = 0.75 inches
      • Answer (Shrinkage): 0.75 inches (or 3/4 inch)
    • 45-degree bends:
      • Thought Process (DBM): Offset depth = 3 inches. Multiplier = 1.414.
      • Calculation (DBM): 3 inches x 1.414 = 4.242 inches
      • Answer (DBM): Approximately 4.24 inches
      • Thought Process (Shrinkage): Offset depth = 3 inches. Shrinkage rate = 3/16 inch per inch.
      • Calculation (Shrinkage): 3 inches x (3/16) inches/inch = 3 x 0.1875 = 0.5625 inches
      • Answer (Shrinkage): Approximately 0.56 inches (or 9/16 inch)
    • Which option has less shrinkage and why might that be important?
      • Answer: The 45-degree bends result in less total shrinkage (0.56 inches vs. 0.75 inches).
      • Importance: Less shrinkage can be important because it means you lose less overall length from your conduit run, which can be critical for maintaining accurate measurements over longer distances or when working with pre-cut lengths of conduit. It also means you may have to make fewer adjustments to your overall conduit length.
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Cool Down

EMT Bending Cool-Down: Quick Check

Instructions: Briefly answer the following questions to reflect on what you learned about EMT conduit bending today.

  1. What is one reason why it's important for electricians to know how to bend EMT conduit accurately?



  2. You need to make a 90-degree bend. If your bender has a 5-inch take-up and you want a finished stub-up of 14 inches, where would you mark the conduit?



  3. In your own words, explain what an

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