Part 4
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Questions and Answers

What does DNC refer to in machining?

  • Denoted Non-Controlled
  • Denied Notified Connection
  • Direct Numeric Control (correct)
  • Designated New Control

    • What is the maximum angle that a template should have when using a hydraulic tracer attachment on a lathe?

  • 30 degrees
  • 15 degrees
  • 45 degrees (correct)
  • 90 degrees

    • In a CNC lathe, what does the Z axis represent?

  • The movement of the carriage
  • The movement of the crosslide (correct)
  • The movement of the stepper motor
  • The movement of the servo motor

    • How are grinding wheels classified?

    <p>According to abrasive type, size and bonding material</p> Signup and view all the answers

    What supports the Headstock in a CNC turning centre?

    <p>Bed</p> Signup and view all the answers

    What is not evident when the amount cut is a very fine thread on the workpiece?

    <p>The back rack angle</p> Signup and view all the answers

    What is a characteristic of a Chucking Centre machine?

    <p>It is built without a tailstock and has a short centre distance</p> Signup and view all the answers

    What type of lubrication system relies on a pump to force oil under pressure into a bearing?

    <p>The enclosed circulating lubrication system</p> Signup and view all the answers

    What is the main function of a forming tool?

    <p>It is used to cut intricate cylindrical profiles</p> Signup and view all the answers

    What is the typical drill point angle for general purpose use?

    <p>118</p> Signup and view all the answers

    What is the primary function of the MCU in a CNC machine?

    <p>It is the nerve centre of the CNC machine coordinating all machine operations</p> Signup and view all the answers

    What is true with respect to a single spindle-double turret on independent slides in CNC machines?

    <p>Either finish turning or threading can be done at the same time</p> Signup and view all the answers

    What is a characteristic of a solid dead centre?

    <p>It is held in the tailstock spindle and does not turn</p> Signup and view all the answers

    In Quadrant 3, the x and z axes have what coordinates?

    <p>-X, -Z</p> Signup and view all the answers

    What carries the tool turret in a CNC turning centre?

    <p>Saddle</p> Signup and view all the answers

    What can a floating reamer holder minimize?

    <p>the effect of reamer misalignment</p> Signup and view all the answers

    What is an advantage of using grease over oil as a lubricant?

    <p>All of the above</p> Signup and view all the answers

    What type of CNC turning centre does not have a turret to hold cutting tools?

    <p>A vertical single turning center</p> Signup and view all the answers

    What should the feed rate be for a roughing cut?

    <p>as high as the cutting tool and the machine can handle</p> Signup and view all the answers

    What is a characteristic that distinguishes a telescoping taper attachment from a plain taper attachment?

    <p>the cross-slide screw is attached to the guide shoe on the telescoping attachment</p> Signup and view all the answers

    What type of CNC turning center is also called the Swiss style turning center?

    <p>A sliding headstock turning center</p> Signup and view all the answers

    With EIA coding, how many rows can program characters be found?

    <p>8</p> Signup and view all the answers

    What is the calculated RPM for drilling a 32 mm hole in leaded steel using a carbide drill?

    <p>1492.09</p> Signup and view all the answers

    What is full format suppression in CNC machining?

    <p>it allows dimensions to be written without the zeros in front of the decimal point</p> Signup and view all the answers

    What is the primary use of a narrow rule?

    <p>To measure distances along a single edge</p> Signup and view all the answers

    What does the acronym PASS stand for in the context of portable extinguishers?

    <p>Point the nozzle, Aim the hose, Spray, Sweep the fire</p> Signup and view all the answers

    What is the pitch of a 3/8 - 16 UNC screw thread?

    <p>0.0625 in</p> Signup and view all the answers

    What does the WHMIS pictogram represent?

    <p>A toxic or fatal hazard</p> Signup and view all the answers

    What is the characteristic of a crosscut sawmill file?

    <p>It is a triangular shaped single cut file used for sharpening mill saws with M shaped teeth</p> Signup and view all the answers

    How are labels handled under WHMIS?

    <p>They are required for all hazardous materials</p> Signup and view all the answers

    What is the purpose of a machinist's rule?

    <p>To measure distances and make precise markings</p> Signup and view all the answers

    What is the main benefit of printing the exam and answer key?

    <p>It enables you to review the exam offline</p> Signup and view all the answers

    A circle drawn in which type of projection would form an ellipse?

    <p>Isometric projection</p> Signup and view all the answers

    What type of tolerancing is used for fully defining form and controlling angular relationships?

    <p>Geometric dimensioning and tolerancing</p> Signup and view all the answers

    What does the abbreviation TYP stand for in machinist blueprint drawings?

    <p>Typical</p> Signup and view all the answers

    What is a micro-inch?

    <p>One millionth of an inch</p> Signup and view all the answers

    Are anti-friction bearings normally dimensioned in machinist blueprint drawings?

    <p>False</p> Signup and view all the answers

    What does the acronym TPF stand for when referring to tapers on machinist blueprint drawings?

    <p>Taper Per Foot</p> Signup and view all the answers

    What is drawn at actual size when referring to a drawing?

    <p>1:1 ratio</p> Signup and view all the answers

    What does the term waviness refer to in surface finishes?

    <p>An unrepeated or random irregularity in the surface finish</p> Signup and view all the answers

    What is the large diameter of a taper, where TR=1:60, d=42mm, TL=120mm?

    <p>45</p> Signup and view all the answers

    What is machining that produces a channel on the diameter of the workpiece?

    <p>Grooving</p> Signup and view all the answers

    What is the fraction 3/20 expressed in decimal form?

    <p>0.15</p> Signup and view all the answers

    What is the term that refers to machining to separate a part from the main bar stock?

    <p>Parting</p> Signup and view all the answers

    In the diagram, how many degrees is angle θ when α = 550 and β = 450?

    <p>39.3 degrees</p> Signup and view all the answers

    What type of lubrication system relies on a pump to force oil under pressure into a bearing?

    <p>The enclosed circulating lubrication system</p> Signup and view all the answers

    Given that 1 inch = 25.4 mm, what is the value below? 91.44 cm = ______ feet

    <p>4</p> Signup and view all the answers

    What supports the Headstock in a CNC turning centre?

    <p>Bed</p> Signup and view all the answers

    Using the formula, if θ = 38 inches and β = 3 feet, what is α equal to?

    <p>55.5</p> Signup and view all the answers

    What is a triangle that has two equal angles called?

    <p>An isosceles triangle</p> Signup and view all the answers

    What is the typical drill point angle for general purpose use?

    <p>118 degrees</p> Signup and view all the answers

    What is true with respect to a single spindle-double turret on independent slides in CNC machines?

    <p>Either finish turning or threading can be done at the same time</p> Signup and view all the answers

    What is the perimeter, in feet, of the parallelogram in the diagram?

    <p>8.35 feet</p> Signup and view all the answers

    How are grinding wheels classified?

    <p>According to abrasive type, size, and bonding material</p> Signup and view all the answers

    What is the small diameter of a taper, where TR=1:40, D=20.4mm, TL=96mm?

    <p>20.6</p> Signup and view all the answers

    What does the Z axis represent in a CNC lathe?

    <p>The movement of the crosslide</p> Signup and view all the answers

    What is the main function of a resolver?

    <p>To measure positional data</p> Signup and view all the answers

    Which type of drill machine is best suited for drilling in very large workpieces that are difficult to position?

    <p>A radial drill machine</p> Signup and view all the answers

    When is running a dial indicator along a workpiece a good way to align the workpiece?

    <p>When the workpiece has a centre hole but the tailstock centre can not be used</p> Signup and view all the answers

    What is the angle of saddle movement to the axis of the machining spindle?

    <p>Parallel</p> Signup and view all the answers

    When using the back face as program zero, what are all X and Z coordinate values?

    <p>All negative</p> Signup and view all the answers

    What is the calculated RPM for drilling a 45 mm hole in Aluminium using a carbide drill?

    <p>2212.09</p> Signup and view all the answers

    What type of transducer is a resolver?

    <p>Positional</p> Signup and view all the answers

    How is an angle denoted with polar coordinates when measured counter-clockwise?

    <p>Positive</p> Signup and view all the answers

    Which of the following angles is not evident when the amount cut is a very fine thread on the workpiece?

    <p>The nose radius</p> Signup and view all the answers

    What is a characteristic of a CNC turning centre that is suitable for large, heavy and odd shaped workpieces?

    <p>They are suitable for large, heavy and odd shaped workpieces that cannot be held on standard turning centres</p> Signup and view all the answers

    Which of the following best describes a forming tool?

    <p>It cuts on its ends</p> Signup and view all the answers

    What is the primary function of the MCU in a CNC machine?

    <p>Its function is to develop appropriate signals from program data for driving servo motors</p> Signup and view all the answers

    What is a characteristic of a solid dead centre?

    <p>It is held in the tailstock spindle and does not turn</p> Signup and view all the answers

    What carries the tool turret in a CNC turning centre?

    <p>Saddle</p> Signup and view all the answers

    What is an advantage of using grease over oil as a lubricant?

    <p>It tends to adhere better to the surface of the part</p> Signup and view all the answers

    What type of CNC turning centre does not have a turret to hold cutting tools?

    <p>A vertical single turning center</p> Signup and view all the answers

    What is the length of the hypotenuse in a triangle with a vertical component of 165 units and a horizontal component of 310 units?

    <p>351 units</p> Signup and view all the answers

    What is the value of COS 45 degrees?

    <p>0.707</p> Signup and view all the answers

    What is the most accurate method of measuring a taper?

    <p>Using a taper micrometer</p> Signup and view all the answers

    What is the actual diameter of a gear if the scaled diameter is 21 mm on a drawing with a scale of 1:10?

    <p>210 mm</p> Signup and view all the answers

    What does the term 'surface roughness' mean when referring to surface finishes?

    <p>The average deviation from the centerline measured in microinces or micro meters.</p> Signup and view all the answers

    What type of key should be used between the hub and a 6 inch diameter shaft?

    <p>Square key</p> Signup and view all the answers

    What is a FN3 fit used for?

    <p>For ordinary steel parts or light shrink fits on thin sections.</p> Signup and view all the answers

    What does the term 'roughness height' mean when referring to surface finishes?

    <p>The average deviation from the centerline measured in microinces or micro meters.</p> Signup and view all the answers

    When preparing a one-inch hole for hand reaming, how much material should be left?

    <p>0.005 of an inch</p> Signup and view all the answers

    How many types of identification does the WHMIS system require?

    <p>Three</p> Signup and view all the answers

    What type of lubrication system allows lubricant to escape into the environment?

    <p>A flow through system</p> Signup and view all the answers

    In a CNC program, what prepares the machine for the upcoming process?

    <p>G: preparatory function</p> Signup and view all the answers

    When is mounting a dial indicator on the face of the chuck a good way to align the workpiece?

    <p>When the workpiece has a centre hole but the tailstock centre can not be used</p> Signup and view all the answers

    What is the calculated RPM for drilling a 0.585-inch hole into 3.5 diameter brass using an HSS twist drill?

    <p>1305.9</p> Signup and view all the answers

    Which of the following best describes carbide as a cutting material?

    <p>It retains its hardness to a very high temperature and is also known as Stellite</p> Signup and view all the answers

    With CNC turning centres and lathes, what does the term 'parting-off' refer to?

    <p>Machining to separate a part from the main bar stock</p> Signup and view all the answers

    What type of CNC turning center is also called the Swiss style turning center?

    <p>A sliding headstock turning center</p> Signup and view all the answers

    What does the term 'resolution' refer to in CNC machines?

    <p>The smallest slide movement the machine can control and act upon</p> Signup and view all the answers

    What is the recommended cutting speed SFPM for high speed steel drills when the workpiece material is Aluminium?

    <p>300</p> Signup and view all the answers

    What should you do if a machine that you were going to use had one of its safety interlocks disabled?

    <p>Do not use this machine</p> Signup and view all the answers

    What is the calculated RPM for drilling a 32 mm hole in tool steel using a carbide drill?

    <p>1492.09</p> Signup and view all the answers

    What is the oldest and simplest work holding device?

    <p>The lathe dog</p> Signup and view all the answers

    In a CNC program, what does the M code M08 cause to happen?

    <p>It will activate the flood coolant</p> Signup and view all the answers

    When using the right hand rule for identifying an axis, what does the thumb represent?

    <p>The Z axis</p> Signup and view all the answers

    Which axis is commonly used to describe the left and right directions on a machine?

    <p>X axis</p> Signup and view all the answers

    Where is the steady rest typically attached on a lathe?

    <p>To the left side of the bed</p> Signup and view all the answers

    What is the effect of reamer misalignment that a floating reamer holder can minimize?

    <p>Decrease</p> Signup and view all the answers

    What is the cutting speed for a 4-inch diameter workpiece when the RPM is 900?

    <p>942.48 RPM</p> Signup and view all the answers

    What is the primary consideration when determining the feed rate for a roughing cut?

    <p>The maximum capacity of the cutting tool and the machine</p> Signup and view all the answers

    What diameter is used when doing spindle calculations for threading operations with a CNC machine?

    <p>The major diameter of the thread being cut</p> Signup and view all the answers

    What is the characteristic that distinguishes a telescoping taper attachment from a plain taper attachment?

    <p>The telescoping attachment uses two binding screws</p> Signup and view all the answers

    What is the advantage of a side wheel grinder over a bench grinder?

    <p>The grinding surface is flat and the work rest to grinding wheel angle does not change</p> Signup and view all the answers

    What is the length of the hypotenuse of a right-angled triangle with a vertical component of 165 units and a horizontal component of 310 units?

    <p>351 units</p> Signup and view all the answers

    Which type of CNC turning center is also called the Swiss style turning center?

    <p>A sliding headstock turning center</p> Signup and view all the answers

    In EIA coding, how many rows can program characters be found?

    <p>7</p> Signup and view all the answers

    What is the value of COS 45 degrees?

    <p>0.707</p> Signup and view all the answers

    What type of turning application is involved when working on a short slug?

    <p>Chucking work</p> Signup and view all the answers

    If the scale on a drawing is 1:10 and the scaled diameter of a gear is 21 mm, what is the actual diameter of the gear?

    <p>210 mm</p> Signup and view all the answers

    What is the calculated RPM for drilling a 32 mm hole in leaded steel using a carbide drill?

    <p>1492.09</p> Signup and view all the answers

    What limits the size of the workpiece when using a milling attachment?

    <p>The size of the vise on the attachment</p> Signup and view all the answers

    What is full format suppression in CNC machining?

    <p>It allows dimensions to be written without the zeros after the decimal point</p> Signup and view all the answers

    Tailstock support for a CNC turning machine is important when the work overhang is more than how many times its diameter?

    <p>When it is more than 4 times its diameter</p> Signup and view all the answers

    What is surface roughness in the context of surface finishes?

    <p>The average deviation from the centerline measured in microinches or micrometers.</p> Signup and view all the answers

    Which of the following is NOT a type of mandrel?

    <p>Gang</p> Signup and view all the answers

    Which type of key should be used between the hub and a 6-inch diameter shaft?

    <p>Square key</p> Signup and view all the answers

    What is a FN3 fit used for?

    <p>For ordinary steel parts or light shrink fits on thin sections.</p> Signup and view all the answers

    What does the term 'roughness height' mean in surface finishes?

    <p>The average deviation from the centerline measured in microinches or micrometers.</p> Signup and view all the answers

    What is the Top View of the figure?

    Signup and view all the answers

    Study Notes

    Overview of a 1st Year Machinist Apprentice

    • A machinist apprentice is a tradesperson who learns to operate and maintain machinery and equipment in a manufacturing setting.
    • The 1st year of apprenticeship focuses on building foundational skills and knowledge in machining and manufacturing.

    Key Skills and Knowledge

    • Machine operation:
      • Familiarity with manual milling machines, lathes, and drill presses.
      • Understanding of machine safety and proper operation procedures.
    • Tooling and measurement:
      • Knowledge of cutting tools, including types, uses, and maintenance.
      • Understanding of measurement instruments, such as calipers and micrometers.
    • Material properties:
      • Familiarity with common materials, including metals, plastics, and composites.
      • Understanding of material properties, such as strength, hardness, and corrosion resistance.
    • Manufacturing processes:
      • Introduction to machining processes, including turning, milling, and drilling.
      • Understanding of manufacturing terminology and concepts.

    Work Environment and Safety

    • Workshop safety:
      • Familiarity with workshop hazards, such as moving machinery and falling objects.
      • Understanding of personal protective equipment (PPE) and safety procedures.
    • Workshop organization:
      • Knowledge of workshop layout and organization principles.
      • Understanding of tool storage and maintenance procedures.

    Apprenticeship Structure and Expectations

    • Apprenticeship duration: Typically 4 years, with 1st year focused on foundational skills and knowledge.
    • Training and assessment:
      • Combination of on-the-job training and classroom instruction.
      • Regular assessments and evaluations to track progress and identify areas for improvement.
    • Workplace expectations:
      • Apprentices are expected to work safely and efficiently, following established procedures and protocols.
      • Active participation in learning and skill development is essential.

    Overview of a 1st Year Machinist Apprentice

    • A 1st year machinist apprentice learns to operate and maintain machinery and equipment in a manufacturing setting.

    Key Skills and Knowledge

    • Machine operation involves familiarity with manual milling machines, lathes, and drill presses, as well as understanding machine safety and proper operation procedures.
    • Tooling and measurement knowledge includes understanding cutting tools, their types, uses, and maintenance, and measurement instruments like calipers and micrometers.
    • Material properties include familiarity with common materials like metals, plastics, and composites, and understanding material properties like strength, hardness, and corrosion resistance.
    • Manufacturing processes include introduction to machining processes like turning, milling, and drilling, and understanding manufacturing terminology and concepts.

    Work Environment and Safety

    • Workshop safety involves familiarity with workshop hazards like moving machinery and falling objects, and understanding personal protective equipment (PPE) and safety procedures.
    • Workshop organization involves knowledge of workshop layout and organization principles, and understanding tool storage and maintenance procedures.

    Apprenticeship Structure and Expectations

    • The apprenticeship typically lasts 4 years, with the 1st year focused on foundational skills and knowledge.
    • The training and assessment process combines on-the-job training and classroom instruction, with regular assessments and evaluations to track progress and identify areas for improvement.
    • Workplace expectations include working safely and efficiently, following established procedures and protocols, and active participation in learning and skill development.

    Safety and Measurement

    • A softener in lifting and hoisting procedures using a sling is a device used to protect the sling from shape edges of the load.
    • The lead of a screw thread is the axial distance a nut advances on a screw thread after one complete turn.
    • When a fiber rope is hitched, the strength of the rope is reduced by 25 percent.
    • A hacksaw pitch blade is used for cutting material with a small cross section, such as high carbon steel drill rod, and the pitch of the blade depends on the material being cut.

    WHMIS (Workplace Hazardous Materials Information System)

    • WHMIS is designed to provide safety for products called "controlled products".
    • A worker's responsibility when dealing with WHMIS is to ensure that appropriate control measures are in place to protect workers.
    • The employer must provide a material safety data sheet for each controlled product used in the shop.
    • A precautionary statement in WHMIS is a phrase that describes direct measures to alert the worker about the level of hazard.

    Machine Tools

    • A CNC (Computer Numerical Control) machine is a type of machine tool that uses a computer program to control the machine's movements.
    • A CNC machine can be programmed to perform a variety of tasks, such as cutting, drilling, and milling.
    • The advantages of CNC machines include increased accuracy, speed, and efficiency, as well as reduced labor costs.

    CNC Turning Machines

    • A CNC turning machine is a type of CNC machine that is used for turning, facing, and cutting operations.
    • The purpose of centre drilling on a CNC turning machine is to provide a 60-degree conical surface for a bearing centre.
    • The program speed when reaming on a CNC turning machine is generally 25 to 50% of that used for drilling.
    • A self-driving centre on a CNC turning machine is used when the entire length of the workpiece must be machined in one pass.

    CNC Machine Components

    • A transducer is a device that monitors external variables and converts them into signals for a machine control unit.
    • A soft limit switch on a CNC machine is a type of virtual or programmed switch that resides in the computer program.
    • A microset adjustable centre on a CNC machine is used to adjust the centre of the workpiece.
    • A facing tool on a CNC machine is used to cut a flat surface at right angles to the axis of the workpiece.

    CNC Programming

    • The surface speed formula used with CNC turning machines calculates the cutting speed based on the diameter of the workpiece.
    • A CNC program can be used to control the machine's movements, including the spindle speed and feed rate.
    • The M code M30 in a CNC program causes the machine to stop executing a program.

    Machine Operations

    • A taper attachment on a lathe is used to cut tapers and eliminates all backlash.
    • A floating reamer holder may decrease the effect of reamer misalignment.
    • An oil mist lubrication system ensures that the oil is always clean and is not affected by oil viscosity.

    Machine Control

    • The MCU (Machine Control Unit) of a CNC machine is the nerve centre of the machine, coordinating all machine operations.
    • The servo drive control in a CNC machine develops appropriate signals from program data for driving servo motors.
    • Machine zero on a CNC machine is the absolute reference point and origin of the machine coordinate system.

    CNC Turning Centers

    • A sliding headstock turning center is a type of CNC turning center that is also called the Swiss style turning center.
    • A twin spindle vertical turning center is a type of CNC turning center that has two spindles.
    • A gang style horizontal spindle turning center is a type of CNC turning center that has multiple spindles.

    Drilling and Cutting

    • The RPM for drilling a hole depends on the material being drilled and the type of drill being used.
    • A hacksaw pitch blade is used for cutting material with a small cross section, such as high carbon steel drill rod.
    • A band saw blade is used for cutting curved shapes and has a specific pitch and number of teeth.

    Grinders and Lathe Operations

    • A grinder is used to grind and polish materials.

    • The flange of a grinder should be one-third the diameter of the wheel.

    • Backlash on a lathe refers to the space between meshing gears.### Machining Operations

    • Machining that produces a channel on the diameter of a workpiece is known as grooving.

    • Machining to separate a part from the main bar stock is known as parting.

    Lathe Specifications

    • The size of a lathe is determined by the largest diameter of workpiece that can be supported over the ways and the greatest length of workpiece that can be supported between centers.
    • The headstock is always attached to the left side of the bed.

    Lathe Components

    • A stop shaft is clamped to the ways to stop the movement of the carriage.
    • A turret stop is clamped to the ways to stop the movement of the carriage.
    • A lathe dog engages a slot in the drive plate, with different types including safety clamp, straight tail, standard bent tail, and clamp.
    • A blotter is a heavy piece of metal attached to each side of a grinding wheel.

    Machining Techniques

    • Profiling is machining of curved surfaces.
    • The feed rate for a roughing cut should be as high as the cutting tool and the machine can handle.
    • The feed rod moves the carriage at a slower rate than the lead screw does for threading.

    CNC Turning Centres

    • Twin spindle-twin turret arrangements are used in high production machining, allowing work to be machined on both ends.
    • Single spindle-single turret arrangements are the most common arrangement and are used in high production machining.

    Work Holding Devices

    • A vise is a very versatile and convenient work holding device.
    • A tapered pin is used to secure a drill chuck to its shank and has a 3 1/2 inch taper per foot.

    Trade Mathematics

    • 1 pound = 0.454 kg and 1 inch = 25.4 mm are common conversions.
    • The amount of taper is expressed as taper per foot in the imperial system.
    • Angles can be calculated using trigonometric functions.
    • A circle drawn in an isometric projection would form an ellipse.
    • Material section lines on a blueprint represent different materials, such as steel, rubber, and others.
    • A set square is used to draw angles, with common angles including 90°, 45°, 45° and 45°, 60°, 30°.

    Fasteners and Surface Finishes

    • A bolt designation includes the diameter, threads per inch, and thread form, such as 3/8 - 16 UNC X4.
    • A machine screw driving recess can be a slotted spanner, hex castle, self-locking, acorn, or hex flange.
    • Surface roughness is the average deviation from the centerline measured in microinches or micrometers.
    • Waviness refers to the distance between repeated wavy patterns on a surface finish.

    Machinist Practice Test

    • The test consists of 120 questions covering various topics in machinist trade.
    • The test can be printed and answered offline, and the answer key can be printed separately.

    Safety and Measurement

    • A narrow rule is a type of rule that has graduations only along one edge.
    • The PASS acronym outlines the proper use of a portable extinguisher: Point the nozzle, Aim the hose, Spray, Sweep the fire.
    • The pitch of a 3/8 - 16 UNC screw thread is 0.0625 inches.
    • The WHMIS pictogram represents a health hazard.

    Machining Operations

    • A crosscut sawmill file is a triangular shaped single cut file used for sharpening mill saws with M-shaped teeth.
    • DNC stands for Direct Numeric Control.
    • The maximum angle for a template using a hydraulic tracer attachment on a lathe is 15 degrees.
    • The Z-axis on a CNC lathe represents the movement of the carriage.

    Lubrication Systems

    • A lubrication system can be classified into different types, including enclosed circulating, drip feed, ring oiler, and splash lubrication.
    • The enclosed circulating lubrication system relies on a pump to force oil under pressure into a bearing.

    CNC Machines

    • A single spindle-double turret on independent slides allows for different diameters to be machined at the same time.
    • A Chucking Centre machine is designed for work that is held in a chuck at one end and supported with a tailstock at the other.
    • The MCU of a CNC machine is the nerve centre that coordinates all machine operations.

    Tooling and Workholding

    • A solid dead centre is used when the entire length of the workpiece must be machined in one pass.
    • A floating reamer holder can decrease the effect of reamer misalignment.
    • A telescoping taper attachment uses two binding screws to set the depth of cut.

    Drilling and Tapping

    • The feed rate for a roughing cut should be as high as the cutting tool and the machine can handle.
    • The calculated RPM for drilling a 32 mm hole in leaded steel using a carbide drill is 1492.09.

    Tolerancing and Dimensioning

    • Full format suppression is used to reduce the number of zeros in the full format dimensions.
    • Geometric dimensioning and tolerancing is used to fully define form and control angular relationships.

    Blueprint Drawings

    • The abbreviation TYP on a blueprint drawing stands for Typical.
    • Anti-friction bearings are not normally dimensioned on a blueprint drawing.
    • The acronym TPF on a blueprint drawing stands for Taper Per Foot.
    • A ratio of 1:1 is drawn at actual size on a blueprint drawing.

    Machining Operations

    • Machining that produces a channel on the diameter of the workpiece is known as turning.
    • Machining to separate a part from the main bar stock is known as parting off.

    CNC Machines

    • DNC refers to Direct Numeric Control.
    • The Z axis in a CNC lathe represents the movement of the carriage.
    • A single spindle-double turret on independent slides in a CNC machine allows for different diameters to be machined at the same time.

    Grinding Wheels

    • Grinding wheels are classified according to abrasive type, size, and bonding material.

    Lubrication Systems

    • The enclosed circulating lubrication system relies on a pump to force oil under pressure into a bearing.

    Drill Point Angles

    • The drill point angle for general-purpose use is 118 degrees.

    Chucking Centre Machines

    • A chucking centre machine is designed for work that is held in a chuck at one end and supported with a tailstock at the other.

    Forming Tools

    • A forming tool is used to cut intricate cylindrical profiles.

    MCU (Machine Control Unit)

    • The MCU is the nerve centre of the CNC machine, coordinating all machine operations.

    Solid Dead Centres

    • A solid dead centre is held in the tailstock spindle and does not turn.

    Lubrication Advantages

    • The advantage of using grease over oil as a lubricant is that it tends to adhere better to the surface of the part.

    CNC Turning Centers

    • A CNC turning centre without a turret to hold cutting tools is a vertical single turning centre.

    Drilling Machines

    • A radial drill machine is best suited for drilling in very large workpieces that are difficult to position.

    Workpiece Alignment

    • Running a dial indicator along a workpiece is a good way to align the workpiece when the carriage is between the headstock and the steady rest.

    Saddle Movement

    • The saddle movement is at an angle of 90 degrees to the axis of the machining spindle.

    Programming Zero

    • When using the back face as program zero, all X and Z coordinate values are positive.

    RPM Calculation

    • The calculated RPM for drilling a 45 mm hole in Aluminium using a carbide drill is 2012.9.

    Transducers

    • A resolver is a type of positional transducer.

    Band Files

    • A band file consists of a series of short files riveted to a steel band.

    Angle Denotation

    • An angle denoted with polar coordinates when measured counter-clockwise is positive.

    Lathe Dogs

    • A safety clamp is a type of lathe dog that engages a slot in the drive plate.

    Tapers

    • The large diameter of a taper, where TR=1:60, d=42mm, TL=120mm, is 45 mm.

    Decimal Equivalents

    • The fraction 3/2 expressed in decimal form is 1.5.

    Triangle Angles

    • An angle of 550 and 450 in a triangle makes angle 50.7 degrees.

    Unit Conversions

    • 91.44 cm is equivalent to 3 feet.

    Triangle Perimeter

    • The perimeter of a parallelogram with sides 38 inches, 3 feet, and 18 inches is 12.33 feet.

    Trigonometry

    • COS 45 degrees is equal to 0.707.

    Measuring Tapers

    • The most accurate method of measuring a taper is using a taper micrometer.
    • A scale of 1:10 on a drawing indicates that the actual diameter of a gear is 10 times the scaled diameter.

    Surface Finishes

    • Surface roughness refers to the average deviation from the centerline measured in microinches or micrometers.

    Key Types

    • A square key is used between the hub and a 6-inch diameter shaft.

    Fits

    • A FN3 fit is used for ordinary steel parts or light shrink fits on thin sections.

    Machine Tools

    • A solid hand reamer should leave 0.002 inches of material before hand reaming.
    • In a CNC program, a G-code prepares the machine for what is coming.

    Lubrication Systems

    • A flow-through system allows lubricant to escape into the environment after use.

    CNC Machining

    • The calculated RPM for drilling a 0.585-inch hole in 3.5 diameter brass using an HSS twist drill is 979.43.
    • Carbide is a cutting material that retains its hardness to a very high temperature and is also known as Stellite.
    • In CNC turning centers, "parting-off" refers to machining the outside diameter of the workpiece.
    • The term "resolution" refers to the smallest slide movement the machine can control and act upon.

    Safety Interlocks

    • If a machine's safety interlock is disabled, do not use the machine.

    Cutting Speeds

    • The recommended cutting speed SFPM for high-speed steel drills when the workpiece material is Aluminium is 300.

    Work Holding Devices

    • The oldest and simplest work holding device is the lathe centre.

    CNC Programs

    • In a CNC program, an M-code M08 activates the spindle in the forward direction.
    • In a CNC program, an M-code M08 does not stop the machine from executing a program.

    Axis Identification

    • When using the right-hand rule for identifying an axis, the thumb represents the X-axis.

    CNC Machines

    • Full format suppression is used to reduce the number of zeros in full format dimensions.
    • In a CNC machine, the diameter used for spindle calculations for threading operations is the major diameter of the thread being cut.

    Turning Applications

    • Chucking work involves working on a short slug.
    • When the work overhang is more than 4 times its diameter, tailstock support for a CNC turning machine is important.

    PLCs

    • A PLC (Programmable Logic Controller) connects RAM directly to binary logic, allowing machining logic.

    Measurement

    • COS 45 degrees is equal to 0.707.
    • The most accurate method of measuring a taper is using a taper micrometer.
    • On a drawing with a scale of 1:10, a scaled diameter of 21 mm corresponds to an actual diameter of 210 mm.
    • Surface roughness refers to the average deviation from the centerline measured in microinches or micrometers.

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