Lesson 1Threading on a conventional lathe: single-point external threading technique, pitch engagement, thread profile checks, and thread length controlThis part covers single-point external threading on a conventional lathe, including tool setup, pitch engagement, infeed methods, thread profile verification, and control of thread length and runout for accurate, repeatable results in local operations.
Thread form, pitch, and diameter terminologyTool geometry and insert selection for threadingSetting compound angle and infeed strategySynchronising pitch with leadscrew and gearboxChecking thread profile with gauges and templatesControlling thread length, runout, and undercutsLesson 2Surface finish for bearing fits: achieving required Ra using finishing passes and tool geometryHere you will learn how to achieve bearing-quality surface finishes on shaft seats by combining proper tool geometry, cutting parameters, and finishing passes, while controlling vibration, built-up edge, and tool wear for Zambian machining standards.
Surface roughness terms and Ra requirementsTool nose radius and rake for fine finishingLight finishing passes and spring cutsControlling chatter and workpiece deflectionCoolant use and chip control for fine finishVerifying finish with comparators and gaugesLesson 3Dimensional inspection methods on lathe parts: micrometers, calipers, dial indicators, and go/no-go gaugesYou will explore dimensional inspection methods for lathe parts, using micrometers, calipers, dial indicators, and go/no-go gauges to verify diameters, lengths, runout, and threads, and to document results against drawing requirements in workshops.
Using calipers for quick checks and layoutOutside micrometers for precise diametersDial indicators for runout and alignmentGo/no-go plug and ring gauges for threadsRecording measurements and tolerancesHandling and caring for precision gaugesLesson 4Workholding methods: 3-jaw chuck, 4-jaw chuck, live center in tailstock, and driving dogs for shaft workYou will study common workholding methods for shaft work, including 3-jaw and 4-jaw chucks, live centers, and driving dogs, learning how to select, set up, and verify each method to ensure concentricity and secure clamping safely.
Using a 3-jaw chuck for general shaft workIndicating and centring in a 4-jaw chuckSupporting long shafts with live centresDriving between centres with dogs and faceplatesReducing runout and deflection on slender shaftsSafety checks for clamping and overhangLesson 5Selecting raw round-bar size and calculating stock allowance for 30 mm to 20 mm stepped shaftThis part explains how to select raw bar size and calculate stock allowance for a 30 mm to 20 mm stepped shaft, considering straightness, cleanup, chucking, and machining allowances for roughing and finishing operations in practice.
Reviewing final shaft dimensions and featuresChoosing bar diameter above largest stepAllowing stock for roughing and finishing cutsConsidering straightness and material conditionLength allowance for facing and workholdingWorked example for 30–20 mm stepped shaftLesson 6Tool selection for each turning step: carbide/ HSS turning tools, parting tools, threading tools, drill bits for center holes, and form/rounding toolsThis part details how to select tools for each turning step on stepped shafts, including carbide and HSS tools, parting and threading tools, center drills, and form tools, matching geometry and grade to material and operation effectively.
Choosing carbide versus HSS turning toolsNose radius and chipbreaker selectionSelecting and setting parting toolsChoosing threading tools and insertsCentre drills and twist drills for centre holesForm and rounding tools for fillets and radiiLesson 7Sequence of turning operations: facing, center drilling, rough turning, finish turning, parting, threading, and chamferingThis part explains how to plan the logical sequence of turning operations for stepped shafts, from facing and center drilling through roughing, finishing, threading, chamfering, and parting, to minimise errors, distortion, and rework in the shop.
Planning operation order from drawing requirementsFacing and establishing reference surfacesCentre drilling and supporting between centresRough turning diameters and shouldersFinish turning critical diameters and fitsChamfering, threading, and parting off safelyLesson 8Cutting parameters: spindle speeds (RPM), feed rates (mm/rev), depths of cut for rough and finish turning on medium carbon steelHere you will learn how to choose spindle speed, feed rate, and depth of cut for roughing and finishing medium carbon steel, balancing tool life, surface finish, and productivity while respecting machine power and rigidity limits locally.
Relating cutting speed, RPM, and work diameterSelecting feeds for roughing and finishing passesChoosing depth of cut by rigidity and power limitsAdjusting parameters for tool wear and chatterEffect of coolant and lubrication on cutting dataUsing tables and catalogues to set starting valuesLesson 9Interpreting shaft dimensions, tolerances, and surface-finish requirementsThis part trains you to read shaft drawings, interpret dimensions, tolerances, and surface-finish symbols, and relate them to functional requirements such as bearing fits, shoulders, and thread engagement on stepped shafts for accurate work.
Linear and diameter dimensioning on shaftsLimit dimensions and fit designationsGeometric tolerances for runout and concentricitySurface-finish symbols and bearing seat needsRelating drawing data to machining strategyCommon mistakes when reading shaft drawings
