An Introduction to Machining Practices

1 AN Introduction TOMACHINING PRACTICESCORNELL UNIVERSITYEMERSON PRODUCT REALIZATION LABORATORY116 FRANK H. T. RHODES HALLITHACA, NEW YORK 14853-3801 Page 2 The Emerson Laboratory What is the Emerson Laboratory?Simply stated, it is an area where students, faculty, staff, and all other members of the Cornell communitymay use the available machine tools to facilitate completion of their projects and/or Engineering students use the shop to support the various projects in their curriculum includinglaboratory sessions. Many users fabricate items related to design projects, such as the HEV and FormulaSAE projects within the engineering college, as well as other team projects throughout the members fabricate equipment needed by faculty for research projects. Emerson may even be usedfor personal fabrication is the Emerson Laboratory?The machine shop (Emerson Manufacturing Teaching Laboratory) is located on the first floor of Rhodes Hall.

2 When entering the building from the front entrance, turn left after the reception door straight ahead (Room 116) is the shop. Feel free to walk in and look of the Emerson Laboratory What can be done in the Emerson Laboratory?Anyone who has had the proper training on the available equipment may use the shop for fabrication ofparts made from the various metal alloys. We are not able to fabricate from wood, phenolic, epoxy glass,and other materials that create large amounts of residual dust. Metal alloys are the only permissiblematerials allowed. There are some exceptions to this rule that should be discussed with shop personnel asthe situation shop keeps a small inventory of tooling, but Emerson does not have all the tooling that might benecessary for all projects. Technical Service Facilities (TSF), located in the basement of Upson Hall, hasa stockroom of tooling available for purchase or use.

3 Tooling may borrowed , if it is available, by usingthe log out system they have in place. TSF also stocks some raw materials ( screws, nuts, bolts, etc.)that may need to be purchased for machines are available in the Emerson Laboratory?The shop currently has a variety of machine tools. In most cases, more than one of each is be aware of the hours of operation of the lab and the limitations of each machine as explained in is a list of available equipment:Horizontal Bandsaws (2)Disc Sander (1)Vertical Bandsaw (1)CNC Milling Machines (2)Drill Presses (3)CNC Lathe (1)Vertical Milling Machines (2)Instrons (2) [used for material testing, load frames]Horizontal Milling machine (1) coordinate measuring Equipment (Metrology Cell)Lathes (9)Welders:Belt Sander (1)MIG, TIG, Stick and Oxy-acetleneThere are signs near each machine to explain their operation and safety rules. If theyare unclear, please ask for a clarification!

4 Page 3 Design Concepts This section is provided to help plan the activities in the shop during the design stage of a project. Ifmanufacturing issues are considered early in the design, time and frustration during the actual fabricationcan be saved. Plan the design thoroughly with specific sketches and detailed drawings for constructionand Machining . The following list of questions is to get you thinking about some important conceptsduring the design process. If you cannot answer all of these questions, do not get frustrated since some ofthem are open ended. The answers will fall into place as experience is gained. Read through this list andfamiliarize yourself with these concepts. Remember, a design that cannot be built is a failure!General design tipsCan the design be made? Will slight modifications make it easier?Is there already something which does what I need?Am I using standard sizes?

5 Will the part have uses other than the intended?Will the part be subjected to harmful environmental conditions?What tradeoffs can I live with in the design?Can it be fabricated?Can it be made in the shop?Where will I get the materials?Which tools will I need to use?How accurate does it have to be? ( what are the tolerances needed?)What are the Machining steps required? Is this the minimum number of steps?How long will it take?Ease of machiningIn what order will I perform the Machining ?What is the easiest material I can work with?What needs to be accurate, and more importantly, what does not?Is this a one of a kind, or will it be duplicated again later?Page 4 The purpose of this manual is to introduce the various hand operated machinery, tools, andassociated tooling available for student use in Emerson will be basic in nature, and should not be considered a certification course inmachine instruction may be required at the time of actual machine use, and will beprovided by laboratory personnel as their time USE OF ANY machine TOOLS MAY RESULT IN SEVEREINJURY OR DEATH.

6 MANDATORY ADHERENCE TO ALL SAFETY RULESIS REQUIRED. EXPULSION FROM THE LABORATORY WILL RESULTFROM NON-COMPLIANCE WITH THESE 5 Safety RulesThese rules have been broken down into three general categories:General Shop SafetyPersonal SafetySafety in the Work EnvironmentGeneral Shop , CD Players, headphones, etc. are not permitted in the food or drink of any kind is permitted in the shop areas, including the CIM Computer equipment operators and their work will be shown the proper respect by those using this accidents and injuries will be reported to the Shop Supervisor transportation of injured individuals is to be done only by qualified personnel. Call 5-1111(Cornell Police) for eye protection will be worn in the machine shop area at all times. Shop users wishing to usetheir personal glasses must document that the lenses and frames are rated for this footwear will be worn at all times.

7 No bare feet, shoes with open toes, slippers, high heels orsandals are all loose clothing, jewelry, neckties, hair, etc. so that it cannot become entangled in gloves are to be worn while operating any of the equipment, with the exception of welding gloves must be worn whenever first aid involving open wounds is being administered toanother. Also, all medical waste will be disposed of in the proper areas, benches, and aisles will be kept clear and free of obstructions. Coats and backpacksshould be stored on the coat rack at the front of the equipment will be used for any purpose other than that for which is was specifically equipment is to be left running while either physically or mentally equipment will be operated without its guards, shields, and safety locks in place and oil or grease spilled on the floor will be cleaned up IMMEDIATELY and disposed of in the keys will be left in the chucks of the lathes or drill one operator per machine is allowed.

8 Special jobs involving more than one operator require thepermission of the Shop Supervisor. Exception to this rule is only during instructional purpose and/ortraining are basic safety rules which apply to the lab in general. Each machine tool and piece of testequipment has its own additional safety rules and considerations. It is the operator's responsibility to befamiliar with these before using any equipment. Training on a particular piece of equipment will be doneat the convenience of the laboratory 6 Operating Procedures non-metallic materials will be machined without prior damaged, broken, or unsafe equipment will be reported to lab personnel are responsible for knowing the correct operating procedures and any associated safety rules forthe equipment they are using. Shop personnel are there to answer questions or show you how to tools and materials will be returned to their correct storage area IMMEDIATELY upon completionof work.

9 Chips and scraps are to be cleaned from machines, floors, and bench tops IMMEDIATELY uponcompletion of is not to be left set up in machines for more than one (1) hour without prior approval. Work leftpast this time may be removed to make equipment available to hours are 8:00 AM to 5:00 PM., with clean up starting promptly at 4:30 PM. Changes to thesehours will be posted on the door in advance. It is the users responsibility to note them and is a clipboard and pen next to each machine - sign in each time you use the machine with yourname and phone Procedures This is a general guideline of the clean-up procedures for the Emerson sure to sweep up the chips on the floor and on the machine . This includes all parts of themachine ( table, tool holder, slots, collets, etc.). up any excess oil that is on the machine or the floor. This includes any oil which may havegotten onto the vise, tabletop, away all the hand tools that were used in their appropriate 7 Terminology Arbor: A device used to hold cutting tools on a milling machine .

10 It is used for cutters rather : The slop or discrepancy between actual distance and measured distance when using thetable s travel handles on a lathe or a milling machine . Backlash occurs when the direction of rotationof the handle is changed: the handle has to be rotated a little before it catches and moves the Drill: A short stubby drill used to start holes. This drill is double ended, where either end can beused. Since it is short and stubby, it does not deflect upon contact with the workpiece and can beused to create an accurately positioned pilot Punch: A metal device that is gently hit with a hammer to create a dimple that helps to guide thedrill bit to the proper location. Without this dimple, the drill bit can walk away from the : The pieces of material that are removed from a workpiece through Machining ; : A device used to hold items. A drill chuck is used to hold a drill bit to the spindles on a drillpress or to the tailstock on a lathe.