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• The question paper is a Question Booklet with four versions identified by the Alpha Codes A, B, C, and D.
• The Question Booklet Alpha Code is printed on the top left of the facing sheet.
• Assigned seating position in the Examination Hall corresponds to a specific Question Booklet Alpha Code.
• If the alpha code on the booklet does not match the code is the seating position, the invigilator must be notified immediately.
• The Question Booklet Serial Number can be found on the top right of the facing sheet.
• An un-numbered Question Booklet should be exchanged for a new one with the same alpha code.
• The Question Booklet is sealed and should only be opened when instructed to start answering.
• After the exam begins, check that the booklet has all 100 questions in order.
• Missing or damaged pages should be reported to the invigilator for a replacement with the same alpha code.
• A blank sheet is included in the Question Booklet for rough work.
• Read the instructions on the reverse of the Answer Sheet before marking answers.
• Each question has four answer choices: (A), (B), (C), and (D).
• Select the correct answer and darken the corresponding bubble on the OMR Answer Sheet using a Blue or Black Ball Point Pen.
• Each correct answer earns 1 mark
• For each wrong answer, 1/3 mark is deducted.
• There is no penalty for unanswered questions.
• Candidates must remain in the hall until the session ends and must hand over the Answer Sheet to the invigilator.
• Ensure the invigilator verifies entries on the Register Number Coding Sheet and signs in the designated space.
• Strict adherence to all instructions is mandatory, and any malpractice will result in disqualification.
• A steel rule measures the depth of keyways and small diameter holes that ordinary steel rules cannot.
• Narrow steel rules, or hook rules are effective here
• Ball pein hammers spread metal in one direction.
• Bastard files are suitable for heavy material reduction.
• A Try square measures with an accuracy of about 0.02 mm per 10 mm length.
• Odd leg calipers cannot be used for making internal measurements.
• Dot punches make light punching marks for position dividers.
• The margin is the narrow surface along the groove of a twist drill that keeps the drill aligned.
• Machine Taps are classified into 4 categories based on Rake angles
• Die nuts are not for cutting new threads.
• Tap extractors remove broken taps.
• Tenacity is the tool material property that prevents breakage or bending under sudden loads or impacts.
• The recommended cutting speed for turning aluminum is 70 - 100.
• Machine tools perform metal-cutting operations using power.
• Spring pole lathes rotate the workpiece by pedal.
• The length of the tail stock is not a statement about lathe specification.
• Four-jaw chuck screw shafts have right-hand BSW threads
• An apron is an 'H' shaped iron casting on lathe bed ways.
• A driving plate is used with a bent type carrier to transfer drive to the workpiece.
• Using centers is a suitable work-holding method for turning lengthy jobs to avoid overhanging.
• Tumbler gears change the spindle speed.
• The lip clearance angle of a twist drill ranges from 8° to 12°.
• Counter sinking is beveling the end of a previously drilled hole.
• The ratchet stop ensures uniform pressure when measuring faces.
• The margin of a drill measures the drill diameter.
• Socket reamers are hand reamers for internal Morse tapered holes.
• In the letter series drill, letter 'A' specifies a drill diameter of 5.944 mm.
• Taper lead angle refers to the angle formed by cutting edges of a taper and reamer axis.
• The suitable angle for counter sinking self-tapping screws is 75°.
• The least count of a standard metric three-point internal micrometer is 0.005 mm.

Formula for Turning Time Calculation:

• Length of cut × RPM / No. of cut x 1000.
• The beveled surface of an outside micrometer with graduation markings is the thimble.

Digital Micrometers:

• Present measuring data via LCD with a 0.001 mm resolution and feature carbide-tipped measuring faces.

Outside Micrometers:

• Have a thimble circumference graduated into 50 divisions, and a spindle thread pitch of 0.5 mm in metric versions.
• Common Vernier calipers used for measuring turning surfaces offer an accuracy of 0.02 mm.
• As shown in the image, Vernier Calipers measure 60.56 mm.
• The image shows the barrel of an External Micrometer.
• Negative zero error occurs when the zero mark on a micrometer's circular scale is above the main scale line when the anvil and spindle faces are closed.
• The reading shown in the image while measuring with a 50 to 75 mm micrometer is 64.13mm.
• Scale graduations on the beam of Vernier Callipers are known as the Vernier scale.
• Micrometers work on the principle of screw and nut mechanisms.
• Ring oiling is an example of a gravity feed method in lubrication.
• High viscosity is not good for lubricants
• Coolant selection is independent of the surface finish required.
• Medium knurling has a pitch of 1.25 mm.
• Mandrels accurately hold the machining outside diameter relative to their bore.
• Tolerance, within the BIS system for limits and fits, is the difference between the maximum and minimum size limits of a component.
• In the expression 20 H7/p6 representing a type of Fit, "H" denotes the Fundamental deviation of the hole.
• In a clearance fit, the maximum clearance is the difference between the minimum hole size and the maximum shaft size.
• Driving plates are used to drive work during turning between centers.
• Ball centers are used for facing jobs on a lathe
• A follower rest is affixed to the outer guideways on the lathe bed.
• Plunger dial indicators operate on the rack and pinion principle.
• Tool center height is adjusted in a four-bolt tool post with parallel packing.
• Maximum interference for the given clearance fit expression is +0.056.
• Callipers and steel rules can measure job diameters to an accuracy of 1 mm.
• Metric tapers are expressed as a number.
• The included angle of a Morse taper is 3°.
• The letter “K” designates conicity of taper.
• Tapers provide self-alignment when assembled using bolts and nuts.
• Tapers are expressed by small or big dia.
• The tangent (tan) value is the ratio between the opposite and adjacent sides of a right-angled triangle.
• The taper angle of metric tapers is 1° 29’ 29”.
• The diameter of a taper pin is specified by the big diameter.
• Number/8 is the formula used to find big diameter dimension of jarno taper
• Plain boring is not produced using the compound slide method.
• In the tail stock offset method, the job is aligned parallel to the axis, and the tool moves at an angle.
• The taper ratio of the British standard pin taper 1:50.
• During taper turning by offsetting the tail stock, the tailstock spindle is set off.
• Morse standard tapers are available in 8 numbers.

Taper Turning Attachment

• Uses the formula Tan𝛷= (D-d) ÷ 𝘐 For calculating the setting angle.
• It is false to say that tightening a screw thread clockwise applies a right-hand direction in the tightening force
• Pitch diameter is the difference between the major diameter and single depth of thread.
• Buttress threads have one flank perpendicular to the axis and another flank that is inclined.
• A worm thread is used in places where motion is transmitted between shafts at varying angles, giving a high speed reduction.
• The minor diameter of a M12 × 1.5 thread is 10.16 mm.
• Buttress threads handle high axial thrust in one direction.

Change Gears

Change gears to cut a 2.5 mm pitch thread on a lathe with a 5 mm pitch lead screw are,

• Driver (50 teeth) & Driven (100 teeth).
• The lead of a M20 × 2.5 triple start thread is 7.5.
• A driver gear with 60 teeth to cut a 3 mm pitch thread is used on a 6 mm pitch lead screw lathe if the driven gear has 120 teeth.
• Screw thread micrometers measure the minor diameter of external threads.
• Hand chasers are intended to correct and finish a thread.
• The root diameter of a thread is a criteria for selecting an interchangeable anvil of a screw thread micrometer.

Matching Table

• Screw thread micrometer = Bolt
• Thread plug gauge = Nut
• Thread ring gauge = Effective diameter of the thread
• The driven gear and the driver gear, when thread cutting, shift based on the pitch of the thread.
• Knuckle threads are used in railway carriage couplings.
• Encoders are located inside the control unit.
• Point-to-point control systems are suited for drilling operations.
• G20 provides data input in inches.
• Hydraulic systems drive CNC machines.
• The workpiece zero point determines the workpiece coordinate system in relation to the machine zero point.
• The code “N006 G00 Z60” means the tool retracts from the workpiece.
• In the program line "G71 P10 Q20 U1.0 W0.5 F0.3", W0.5 defines the depth of cut per pass in the Z axis.
• G75 G code is not used for thread cutting. The program G74 R4.0; G74 Z -50.0 Q8000 F0.05 is a drilling operation.
• ATC (Automatic Tool Changer) in CNC machines automatically swaps tools.
• Incremental programming systems reference the previous tool location for the next tool location.
• In the ISO designation PCLNL2525M – 12 the letter 'P' designates clamping of insert.
• A manual part program does not require a compiler program.
• The tool nose radius compensation (G41 and G42) is essential in taper turning and ball turning.
• Recirculating ball screws prevent backlash in positioning tools in CNC machines.