MACHINE SHOP SAFETY ALWAYS WEAR SAFETY GLASSES Even when you are not working on a machine, you must wear safety glasses. A chip from a machine someone else is working on could fly into your eye. MACHINING Follow directions. If you don t know how to do something, ask. Before you start the machine: Study the machine. Know which parts move, which are stationary, and which are sharp. Double check that your workpiece is securely held. Remove chuck keys and wrenches. Do not leave machines running unattended. Clean up machines after you use them. A dirty machine is unsafe and uncomfortable to work on. Do not use compressed air to blow machines clean. This endangers people's eyes and can force dirt into machine bearings. Report all broken or non-working machines. CLOTHING, JEWELRY, AND HAIR Wear long pants (to your shoes). Wear short sleeves or roll up sleeves. Wear closed toe shoes and socks. Remove all jewelry - watches, bracelets, rings, necklaces, dangling earrings. Long hair or beards must be tied back. If your hair is caught in spinning machinery, it will be pulled out if you're lucky. If you're unlucky, you will be pulled into the machine. No ties, scarves, and dangling clothes. SAFE CONDUCT IN THE MACHINE SHOP Be aware of what's going on around you. For example, be careful not to bump into someone while they're cutting with the bandsaw (they could lose a finger!). Concentrate on what you're doing. If you get tired, leave. Don't hurry. If you catch yourself rushing, slow down. Don't rush speeds and feeds. You'll end up damaging your part, the tools, and maybe the machine itself. Listen to the machine. If something doesn't sound right, turn the machine off. Don't let someone else talk you into doing something dangerous. Don't attempt to measure a part that's moving. No fooling around. VIOLATIONS OF THESE RULES WILL RESULT IN IMMEDIATE REMOVAL FROM THE MACHINE SHOP. Georgia Institute of Technology
George W. Woodruff School of Mechanical Engineering ME 2110 - Creative Decisions and Design Summer 2009 STUDIO 4A - Machining In this lab you will learn about machine shop safety and machining techniques. You will make two parts: i) a nametag and ii) a coupler for a motor shaft. Deliverables For those starting in week 1 Week of June 8 in studio: One of the finished parts (coupler or nametag) Week of June 22 in studio: Both finished parts For those starting in week 2 Week of June 15 in studio: One of the finished parts (coupler or nametag) Week of June 22 in studio: Both finished parts Process Plan for Nametag Note: All dimensions in inches. Do not remove more than 0.020 inches per cut. Do not cut machine or vise when milling. Use wooden spacer to elevate or overhang part to provide clearance between vise and cutting tool. Using Mill: 1. Mill outside dimensions of the block to 2.300x0.25x0.950: a. Clamp on Two smooth sides with a spacer under the part b. Face top and one end c. Slide the part to the other end of the clamp and machine the opposite end to length d. Flip part in vice and machine the bottom side to the proper dimension e. Rotate part 90 in vice and face one of the edges that was clamped f. Rotate part 180 in vice and machine the remaining end to length 2. Mark lines on the part at the correct dimensions for the angled bottom edges. 3. Mill off the angled edge to the appropriate dimension. Repeat for the opposite side 4. Mark holes at the correct locations in the top face of the part. 5. Drill holes using #25 drill bit. 6. Using a dremel tool, etch your first name onto the nametag.
Process Plan for Coupler Note: All dimensions in inches. Do not remove more than 0.020 inches per cut. Readings on the cross slide are radius, not diameter; so removing 0.010 inches from part will result in diameter being reduced in size by 0.020 inches. Do not hit chuck with cutting tool or tool post when machining. On a lathe: Face = machine the flat end of part; this is a radial cut. Turn = machine curved side of the part; this is an axial cut. Using lathe: 1. Chuck part on its outer diameter (OD); make sure part is properly seated in chuck jaws and against chuck face. 2. Face one end (i.e., smooth the end; do not machine part to final length). 3. Turn as much of shaft as possible to 0.900 diameter. 4. Turn 0.500 X 0.500 diameter segment. 5. Flip part in lathe and chuck on 0.500 diameter. 6. Face other end, in doing so machine part to final length. 7. Turn remainder of shaft to 0.900 diameter. 8. Turn 0.750 X 0.500 diameter segment. 9. Drill 0.750 X 0.116 diameter hole using a #32 drill in tail stock. Using drill press or milling machine: 10. Drill radial hole using #36 drill. Use wooden spacer under part. 11. Tap hole drilled in step 10 with 6-32 UNF thread tap; use head of drill press or milling machine to keep tap straight. Use wooden spacer under part. 12. Thread 1/2-20 UNF segment with die; use head of drill press or milling machine to keep die straight.
Nametag All Tolerances ±0.010 unless otherwise specified
Coupler 1/2-20 UNF 6-32 UNC THRU 0.500 0.900 +0.000 0.500-0.005 0.500 0.650± 1/32 0.750 0.250 0.116 φ (#32 Drill) 0.750 DP All tolerances ±0.010 unless otherwise specified