MMAN1130_Final_report University of New South Wales MMAN 1130

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Final Report Assignment School of Mechanical and Manufacturing Engineering MMAN1130 - Design and Manufacturing Justin Duong – z5257944 25/04/21 1 Table of Contents Part A – Machining Theor... y....................................................................................................................3 1.1.1 Difference Between 3-axis, 4-axis, and 5-axis...........................................................................3 1.2.1 Machinist Instructions..............................................................................................................4 1.3.1 Conveyor Belt Tolerance...........................................................................................................5 1.3.2 Conveyor Belt Bilateral Limit.....................................................................................................5 1.3.3 Interference Fit explained.........................................................................................................5 1.4.1 Turning Operations for Candlestick...........................................................................................5 Part B – CAD Assembly and Process Planning Documents.....................................................................6 2.1.1 Assembly Chart.........................................................................................................................6 2.2.1 Assembly Drawing....................................................................................................................7 Part C – HV Manufacture Study of CNC Machining Assessment Component........................................8 3.1.1 Comparison of Three HV Manufacturing Methods...................................................................8 3.2.1 Cost Analysis of Each HV Manufacturing Method...................................................................11 3.3.1 Method Work Sheet of Primary Component..........................................................................12 3.3.3 Routing Chart..........................................................................................................................14 Bibliography.........................................................................................................................................15 Table of Figures Figure 1 - Three axis diagram with example..........................................................................................3 Figure 2 - Four axis diagram with example............................................................................................3 Figure 3 - Five axis diagram with example.............................................................................................4 Figure 4 - Assembly chart......................................................................................................................6 Figure 5 - Assembly cross-section..........................................................................................................6 Figure 6 - Assembly drawing..................................................................................................................7 Figure 7 - Routing chart.......................................................................................................................14 Table of Tables Table 1 - Cost analysis..........................................................................................................................11 Table 2 - Primary component work sheet............................................................................................12 Table 3 - Complementary component work sheet...............................................................................13 2 Part A – Machining Theory 1.1.1 Difference Between 3-axis, 4-axis, and 5-axis The number of axes a CNC machine has refers to the range of motion available to the machine which can be used to create parts. The difference between CNC mills is the number of axes the machine has access to, which then dictates the complexity of the parts that can be made. A 3-axis machine can move the milling drill in the X, Y and Z plane which are all linear directions [1], these machines are suited for milling on one surface. Further, milling on other sides would require adjusting the stock in the fixture which can reduce milling accuracy. Figure 1 - Three axis diagram with example A 4-axis machine can move the milling drill just like a 3-axis machine, however, also introduces a rotational axis that rotates the fixture on the X-axis (A-axis of rotation) [1]. This allows for more complexity in part manufacturing like creating cylindrical parts and milling on other surfaces without needing to change fixtures. Figure 2 - Four axis diagram with example 3 A 5-axis machine can move the milling drill just like a 3-axis machine, however, also introduces a two rotational axis that rotates the fixture on the X-axis and Y-axis (A-axis and Baxis of rotation). By adding a second axis of rotation any compound angle can be achieved and simultaneously rotating both axis at the same time allows for fully continuous machining, which can achieve highly complex 3D surfaces [1]. Figure 3 - Five axis diagram with example 1.2.1 Machinist Instructions 1. Make a marking in the steel plate using a marker. 2. Line up the centre punch with the marking on the steel and hit the centre punch with a hammer to make a dent in the steel plate. 3. Attach spot drill head onto drill press and line the drill bit above the dent. 4. Apply machine oil to lubricate the drill, turn on the drill press and lower the drill bit into the steel plate slightly to enlarge the hole [2]. Brush off any chips left in the hole or on the plate. 5. Swap the drill bit to a 11mm drill head and line the drill bit above the guide hole [3]. 6. Apply machine oil to lubricate the drill and lower the drill bit into the steel plate until it completely passes through the steel plate. Brush off any chips left in the hole or on the plate. 7. Insert 75mm-long 12mm two-flute taper tap with 1.5mm spacing between each thread (M12 x 1.5 x 75) into a tap wrench and tighten until secure [3]. 8. Line tap up perpendicular to the hole and twist until the tap catches onto the plate. 9. Remove the tap and apply machine oil to lubricate the hole. 10. Continuously make a full revolution clockwise and half a revolution counter clockwise until the tap passes through the material [4]. 11. Remove the taper tap and repeat steps 9 – 11 with a bottoming tap. 12. Remove bottoming tap and check threaded hole with a M12 x 1.5 screw. 13. Repeat tapping process if necessary else clean off plate. 4 1.3.1 Conveyor Belt Tolerance Tolerance for all diameters should be 0.4mm larger for interference fit and inaccuracies of CNC machines. Since this design is for a shaft and bearing, you wouldn’t want the bearing to be loose and spinning on the shaft thus an interference fit would be used. This can be achieved by increasing the radius size by 0.15mm but since diameter is used then 0.3mm should be added to the measurements. CNC machines are not perfect and have inaccuracies, so to account for this and keep interference fitting, we would add another 0.05mm for radius but since diameter is used then another 0.1mm needs to be added. 1.3.2 Conveyor Belt Bilateral Limi [Show More]

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