Lesson 1Workhardening, built-up edge (BUE), and effects on tool life and surface finishThis section examines workhardening and built-up edge in 6061, explaining how they arise and damage tools and finish. You will learn parameter, geometry, and coolant adjustments that limit BUE, rubbing, and premature edge failure, useful for local machining practices.
Mechanisms of workhardening in 6061How BUE initiates on cutting edgesEffects on tool wear and chippingSurface finish and dimensional errorsParameter changes to reduce BUETool and coolant choices to limit BUELesson 2Selecting tool materials and coatings for aluminium (carbide, uncoated vs DLC/AlTiN)Here you will compare carbide grades and coating options for aluminium 6061. The section explains when to use uncoated, DLC, or AlTiN tools, considering adhesion, heat, built-up edge, and cost in both dry and coolant-assisted milling, adapted for Gambian conditions.
Micrograin carbide grades for aluminiumUncoated tools and adhesion behaviourDLC coatings for abrasive or dry cuttingWhen AlTiN is acceptable on aluminiumCoating impact on heat and chip flowCost versus performance trade-offsLesson 3Coolant and lubrication strategies for aluminium (flood coolant, mist, or dry with lubricant)Here you will compare coolant and lubrication methods for 6061, including flood, mist, MQL, and near-dry cutting. The section covers heat removal, chip flushing, safety, and how lubrication reduces built-up edge and improves surface finish in tropical climates.
Flood coolant flow and nozzle aimingMist and MQL setup considerationsDry cutting with external lubricantCoolant chemistry for aluminium alloysManaging foaming and corrosion riskCoolant maintenance and filtrationLesson 4Choosing number of flutes and tool diameters trade-offs for chip evacuation and spindle powerHere you will learn how flute count and tool diameter affect chip evacuation, spindle load, and stability in 6061. The section guides selection of 2, 3, or 4 flutes and diameter sizing for slotting, roughing, and finishing operations in small-scale setups.
Two-flute tools for chip evacuationThree-flute cutters for roughing 6061Four-flute tools for finishing passesDiameter choice versus spindle powerChip packing and slotting behaviourBalancing rigidity and reach needsLesson 5Metallurgical properties of aluminium 6061 relevant to milling (strength, thermal conductivity, chip formation)You will study the metallurgical traits of 6061 that affect milling, including strength, hardness, thermal conductivity, and chip formation. The section links temper, heat generation, and chip shape to tool wear, chatter, and surface finish for practical use.
6061 composition and common tempersYield strength and machinability linksThermal conductivity and heat flowChip formation and chip thicknessEffect of temper on burrs and finishResidual stresses and part distortionLesson 6Tool life estimation and monitoring methods for batch productionThis section presents methods to estimate and monitor tool life in batch production. You will use wear criteria, Taylor equations, counters, and in-process signals to schedule tool changes and avoid scrap or catastrophic failures in local production.
Tool wear types and failure modesDefining end-of-life wear criteriaBasic Taylor tool life equation useUsing part and time based countersSpindle load and vibration monitoringTool life tracking in CNC controlsLesson 7Recommended tool types and sizes for pocketing and holemaking: face mills, flat end mills, slotters, drill vs annular cutter vs helical interpolationThis section details tool types and sizes for pocketing and holemaking in 6061. You will compare face mills, end mills, slotters, drills, annular cutters, and helical interpolation, focusing on rigidity, chip evacuation, and cycle time for efficiency.
Face mill sizing for surfacing 6061Flat end mills for pockets and slotsHigh-feed and slotting strategiesTwist drills versus annular cuttersHelical interpolation for precise boresTool length and rigidity selectionLesson 8Tool geometry for aluminium: helix angle, rake, margin, polished flutes to prevent BUEThis section explains cutter geometry features that improve aluminium machining. You will learn how helix angle, rake, margin width, and polished flutes influence cutting forces, chip evacuation, and resistance to built-up edge in 6061.
High rake angle for free cuttingHelix angle choices for 6061Margin width and tool guidancePolished flutes and chip evacuationCorner prep and edge hone sizeGeometry to reduce built-up edgeLesson 9Climb vs conventional milling in aluminium: advantages, when to use eachYou will compare climb and conventional milling strategies in aluminium 6061. The section explains chip thickness profiles, tool deflection, backlash concerns, and when each method is preferred for roughing, finishing, and thin-walled parts in workshops.
Chip thickness in climb vs conventionalBacklash and machine condition limitsRoughing strategy selection in 6061Finishing passes and wall stabilityTool deflection and dimensional errorEntry, exit, and workholding effectsLesson 10Typical feed, speed, and depth-of-cut ranges for roughing and finishing aluminium 6061 (tabulated for common tool diameters)This section defines practical starting feeds, speeds, and depths of cut for roughing and finishing 6061. You will compare ranges by tool diameter, operation type, and machine rigidity, then learn how to adjust safely from tabulated values for local machines.
Roughing vs finishing parameter objectivesTabulated ranges by tool diameterAdjusting for spindle power and rigidityEffect of radial vs axial engagementChip load per tooth and feedrate mathScaling values for small and large tools
