COORDINATOR: Wan Anuar bin Wan HasssanINSTRUCTORS: Hazami bin Che HussainAsmizam bin MokhtarPROJECT MEMBERS: Muhammad Amirul Azreen bin Mohd Zulkefli (MB12045)Lee Heyy Dee (MB12101)Muhammad ‘Abid bin Ibrahim (MB12009)REPORT FOR MILLING PROJECTMECHANICAL TECHNOLOGY LABORATORY 2SEMESTER 2 2012/2013
1REPORT FORMILLINGPROJECTMECHANICAL TECHNOLOGYLABORATORY 2SEMESTER 2 2012/2013INTRODUCTIONWhat is milling?Where we can use milling?How many process involves?PROCEDURESEnd MillingChamfer MillingFace MillingDrillingCounterboringCountersinkingReamingTappingCONCLUSION AND RECOMMENDATIONSWhat do we get?Important things?MILLINGPROJECTMilling is the mostcommon form ofmachining, amaterial removalprocess, which cancreate a variety offeatures on a part bycutting away theunwanted material
2INTRODUCTIONMilling is the most common form of machining, a material removal process, which cancreate a variety of features on a part by cutting away the unwanted material. The milling processrequires a milling machine, workpiece, fixture, and cutter. The workpiece is a piece of pre-shaped material that is secured to the fixture, which itself is attached to a platform inside themilling machine. The cutter is a cutting tool with sharp teeth that is also secured in the millingmachine and rotates at high speeds. By feeding the workpiece into the rotating cutter, materialis cut away from this workpiece in the form of small chips to create the desired shape.Milling is typically used to produce parts that are not axially symmetric and have manyfeatures, such as holes, slots, pockets, and even three dimensional surface contours. Parts thatare fabricated completely through milling often include components that are used in limitedquantities, perhaps for prototypes, such as custom designed fasteners or brackets. Anotherapplication of milling is the fabrication of tooling for other processes. For example, three-dimensional molds are typically milled. Milling is also commonly used as a secondary processto add or refine features on parts that were manufactured using a different process. Due to thehigh tolerances and surface finishes that milling can offer, it is ideal for adding precisionfeatures to a part whose basic shape has already been formed.
3PROCEDURES1) Six Sides Cuttingi. Vise is aligned and work piece is secured in the vise.ii. Face Mill/End Mill all four sides of the work piece to get the accurate dimension of Length(L) and Width (W). (L = 100 mm and W = 48 mm).iii. Face Mill the top and the bottom of the work piece to get the desired Height (H = 24 mm).” A face mill machines a flat surface of the workpiece in order to provide asmooth finish. The depth of the face, typically very small, may be machined in asingle pass or may be reached by machining at a smaller axial depth of cut andmaking multiple passes.”2) Milling A Shoulderi. Vise is aligned and work piece is secured in the vise.ii. Edge Finder is used to find the edge/side for the front side, than set the y-axis on DRO to0.iii. Manually, the y-axis of the table is moved so that the 0 reading of y-axis on DRO changeto 23 mm.iv. Face Mill the top of the work piece to get the desired Height (H = 24 mm).
43) Chamfering 3mm x 45° and Centering The Drill Holes“A chamfer end mill makes a peripheral cut along an edge of the workpiece or afeature to create an angled surface, known as a chamfer. This chamfer, typicallywith a 45 degree angle, can be machined on either the exterior or interior of apart and can follow either a straight or curved path.”i. Vise is aligned and work piece is secured in the vise.ii. Use countersunk to cut the chamfer 3mm x 45°.iii. Make centering using center drill for all holes need to drill on the work piece.iv. RPM that required for center drill is calculated.
54) Holes drilling“A drill enters the workpiece axially and cuts a hole with a diameter equal to thatof the tool. A drilling operation can produce a blind hole, which extends to somedepth inside the workpiece, or a through hole, which extends completely throughthe workpiece.”i. The holes in the work piece is drilled based on the according size in the figure.ii. Cutting speed that is used: 20m/min.iii. Coolant is used.
66) Thru holes tapping“A tap enters the workpiece axially and cuts internal threads into an existing hole.The existing hole is typically drilled by the required tap drill size that willaccommodate the desired tap. Threads may be cut to a specified depth insidethe hole(bottom tap) or the complete depth of a through hole (through tap).”i. Hand tap is used to produce thread as specified on the drawing.ii. Taper tap is used as a starting, followed with plug and it is finished with bottoming tap.iii. Coolant is used.
77) Counterboring“Acounterbore tool enters the workpiece axially and enlarges the top portion ofan existing hole to the diameter of the tool. Counterboring is often performedafter drilling to provide space for the head of a fastener, such as a bolt, to sitbelow the surface of a part. The counterboring tool has a pilot on the end toguide it straight into the existing hole.”i. The right size of counterboring tool is selected to produce step hole for HCSS M10.ii. The pilot holes are checked to make sure there are exist before step holes are cut usingcounterboring tool.iii. RPM for counterboring process is calculated.iv. The counterbore is brought close to the work and it can be seen that the pilot turns freelyin the drilled hole.v. The machine is started, cutting fluid then applied, and the required depth iscounterbored.
88) End milling of slots“An end mill makes either peripheral or slot cuts, determined by the step-overdistance, across the work piece in order to machine a specified feature, such asa profile, slot, pocket, or even a complex surface contour. The depth of thefeature may be machined in a single pass or may be reached by machining at asmaller axial depth of cut and making multiple passes. The work piece is securedon the table of the milling machine by using the vice.”i. Slot drill is used to machine the slot as shown in the drawing.ii. The edge is find to set the origins or reference points.iii. The slot is made and the cutting speed is 15m/min.iv. The depth of cut should be 0.55mm - 1mm.v. Depth of slot is 2mm, multiple cut might be needed.
99) Chamfering“A chamfer end mill makes a peripheral cut along an edge of the workpiece or afeature to create an angled surface, known as a chamfer. This chamfer, typicallywith a 45 degree angle, can be machined on either the exterior or interior of apart and can follow either a straight or curved path.”i. Chamfers (1.5mm x 45°) is made using chamfering tool or countersunk 45°.
10THE TYPE OF CUTTER MATERIAL, ITS CUTTING SPEED (CS), AND ITS SPINDLESPEED (RPM).End milling- High Speed Steel (HSS)- 30-40 (SFM)- 795 (RPM)Slot Drillimg- High Speed Steel (HSS)- 30-40 (SFM)- 795 (RPM)Chamfer milling- High Speed Steel (HSS)- 30-40 (SFM)- 795 (RPM)Face milling- Carbide- 50-250 (SFM)- 1500 (RPM)Counterboring- High Speed Steel (HSS)- 30-40 (SFM)- 1390 (RPM)Drilling- High Speed Steel (HSS)- 30-40 (SFM)- 1390 (RPM)
11Countersinking- High Speed Steel (HSS)- 30-40 (SFM)- 1390 (RPM)Reaming- High Speed Steel (HSS)- 30-40 (SFM)- 1390 (RPM)Edge Finder- High Speed Steel (HSS)- 30-40 (SFM)- 100(RPM)Tapping- Using hand
12CONCLUSION AND RECOMMENDATIONSFrom this activity, we have learned how to organize the milling machine and understandthe operation involved. Besides that, we also know the purpose of the main parts of thismachine. From the laboratory practice also we realize that the cutter diameter should be chosenin such a manner that it will not interfere with fixtures and other components in the setup.Before begin the operation, we must make sure that the milling cutter that would be used wasnot dull. The laboratory activities also provide us the information about the various type ofmilling machines and cutters available for different milling process in the manufacturing worldprocess. In addition, we had gained the knowledge of understanding their usage and functionwhere it can produce different shapes of work piece with different types of surfaces – smooth orrough. This lab session also provide a student how to calculate and estimate a suitable FEEDand RPM. Moreover, student should are given to do their project individually. The purposebehind this is to improve their skills and give more confidences once they do that. Besides that,students also should be neat, tidy, and safely dressed, develop a responsibility for personalsafety and the safety of other students. We should never think that because we are wearingsafety goggles our eyes are safe. If the lenses are not made of approved safety shatterproofglass, serious eye injury can occur. All safety precautions are also taken seriously with theclear explanation from the instructor.