Chapter 7: Knowledge Check

Check Your Knowledge: Chapter 7

Quiz yourself using the following chapter review questions to check how well you can recall the material.

Review Questions

1. True or false: Similar to thread designations, a saw blade is described by the number of teeth in one inch of length.
2. What type of sawing will require the least effort?
   1. Vertical Bandsaw
   2. Chop Saw
   3. Horizontal Bandsaw
   4. Shop helper
3. True or false: Do not wear gloves while cutting parts on the saw because the blade could catch the glove and pull the hand and/or fingers into the blade.
4. True or false: It is acceptable to push a part into a saw blade with a piece of wood.
5. True or false: Having at least three teeth engaged in the part will help stabilize the saw when cutting.
6. Got Chips Accordian:
   1. Chips are like tea leaves – they tell a story.
   2. Where there is smoke, there is…
   3. Bigger chips aren’t always better
7. Which is the best course of action to take when preparing for and performing machine work in the shop?
   1. Sweeping up the chips on the floor between cuts so that people do not walk on them, and track them throughout the shop
   2. Ensure the coolant tank is full before the machine is started up.
   3. Laying your tools out neatly as a doctor does for a surgery.
   4. All of the above
8. Which is the best course of action to take when preparing for and performing machine work in the shop?
   1. Ensure the coolant tank is full before the machine is started up.
   2. Sweeping up the chips on the floor between cuts so that people do not walk on them, and track them throughout the shop.
   3. Laying your tools out neatly as a doctor does for a surgery.
   4. All of the above
9. True or false: It is necessary to clamp a round bar to a plate or block when sawing on the vertical bandsaw.
10. Use the correct term to complete the sentence. If you are not careful while using a shop saw, the part can become damaged from the __________ generated by the cutting blade.
11. Bandsaw blade characteristics: Accordian
    1. The pitch is the distance between each tooth. Use this to determine the minimum thickness of the material to be cut.
    2. The width of the blade will determine the size of the corner that can be cut.
    3. The kerf of the blade is important to remember when determining the overall material needed for the job.
12. Use the correct term to complete the sentence. When using a chop saw to cut mild steel parts, an __________ blade is the best choice.
13. There is a relationship between the band saw blade, the speed or RPM that i moves at, and the material to be cut: Accordian
    1. On soft material, use a blade with a low tooth number designation.
    2. When cutting mild steels, a slower speed of the blade is needed to allow the saw time to cut into the material.
    3. As the hardness of the material goes up, so should the number of teeth of the blade being used to make a cut.
14. True or false: Setting the guide arms close to the material being cut on the horizontal band saw will assist the blade in cutting properly.
15. Work-holding and the types of saws: Accordian:
    1. The horizontal band saw requires the least effort when making the actual cut.
    2. The vertical band saw does not have a vice. The material is typically smaller, and needs to be physically pushed into the blade with your hands
    3. The chop saw benefits from being quick
16. Use the correct term to complete the sentence. The __________ saw could be considered the most productive saw in the shop.

Answer Key

1. True – Yes, Illustrated above are three variable pitch blades. The one on top is the easiest to see. It has between 5 and 8 teeth in one inch of length.
2. Horizontal Bandsaw – This is the best choice. The part is held in a vice, and gravity brings the saw down onto the part.
3. True – Yes, do not wear gloves near any saw, or moving parts in the shop. Gloves can get caught in the equipment and pulled into the blades.
4. True – Yes. It is very easy to get another piece of wood when the one being used gets cut in the saw, as it would be to grow a new finger.
5. True – Yes, the pressure of the blade pushing into the part is spread across all of the teeth. This will help the blade to cut smoothly.
6. Accordian answer:
   1. When chips can be seen coming off of the blade, and the sound is smooth and consistent, it indicates an efficient and productive cutting process.
   2. Dull teeth. If chips are not being formed, the blade is rubbing more than cutting. This will lead to excessive heat and premature wearing of the saw blade.
   3. Unless you have some salsa, this isn’t good. Excessive cutting pressure can cause overly large chips. While this may seem efficient, the teeth will eventually break, and then it will go back to rubbing the part, and work hardening it. When the part is work hardened, it may be unacceptable for use on the customers part…
7. All of the above –Yes, definitely. Keeping the area clean, and organized will benefit the work being done. Machinists are highly skilled workers, just like a surgeon. Organization, and cleanliness shows pride in craftsmanship.
8. All of the above – Yes, definitely. Keeping the area clean, and organized will benefit the work being done. Machinists are highly skilled workers, just like a surgeon. Organization, and cleanliness shows pride in craftsmanship.
9. True – Yes, Clamping the bar to a plate or block will keep it from rotating while being cut.
10. heat – Yes, The heat from cutting can change the material properties in the area that is being cut. Check the customer specifications to determine if using a chop saw is allowed.
11. Accordian answer:
    1. For example, an 8-tooth blade has 8 teeth per inch. To calculate the pitch:
       • 1 ÷ 8 = 0.125 inches (distance between each tooth).
       • A minimum of three teeth should be engaged with the material at all times.
       • 0.125 × 3 = 0.375 inches (minimum material thickness for an 8-tooth blade).

       This means a material thickness of at least 0.375 inches is needed when using an 8-tooth blade to ensure a proper cut.

    2. For example; A blade with a 1.0-inch width is designed for a straight cut. A blade with a .25-inch width can more readily be guided around corners and features.
    3. The material removed due to the blade cutting through it is called the kerf. When calculating the length of material needed for the job, add up the following: the finished part length, extra material to hold on to, and the material lost from the sawing operation. The kerf is an important part to remember when estimating the overall material required.
12. aluminum oxide – Yes, Aluminum oxide blades are designed to cut ferrous materials.
13. Accordian:
    1. Soft material needs to have room between the teeth for the chips to move. A fine tooth blade on aluminum will plug up, and start to heat up. This can cause the blade to stop in the material, and possibly damage the saw.
    2. If the blade is moving too fast when cutting steel, the blade will be rubbing more than cutting. This will generate heat, and wear down the teeth. Then the part will heat up causing it to work-harden.
    3. A variable tooth blade can cut a wider range of material. From the beginning of Chapter 7, a 5-8 tooth blade could be chosen to cut aluminum. A 10-14 blade would be used on mild steel
14. Yes, The guide arms support the pressure from the blade pushing down on the material.
15. Accordian answers:
    1. The part is held in a vice. If the material is very long, the end can be supported with a stand. Gravity will feed the saw through the material. Go prepare for the next job while waiting.
    2. Extra care must be used when cutting on the vertical band saw. Round parts can have a clamp attached to keep them from spinning out of grasp. Fingers will not grow back, so use a push stick when the parts are small.
    3. A vice is used to hold the parts when cutting, as on the horizontal. With the proper blade, parts can be cut very quickly. The cost is less accuracy, and the heating up of the material.
16. horizontal – Yes, Once setup, and cutting, the machinist is free to prepare the next job, or some other task.