MACHINE SHOP RULES AND REGULATIONS

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1 General MACHINE SHOP RULES AND REGULATIONS The College of Engineering Machine Shop was established for support of student course work and research. Every effort will be made to make the shop available for these projects. Students of Engineering, or other programs on campus, who desire to use this equipment for educationally-related activities are required to abide by the following rules and regulations. Rules and Regulations 1. Students are not allowed to use the equipment in the Shop without going through safety training checkout on each of the machines to be used, passing a written safety test, and completion of the Student Request for Machine Shop Use form (with appropriate approvals). Upon completion of the above a student will be given one of the following badges: Limited Access (Yellow) Access is only during the times there is an authorized supervisor on duty in the lab. Prior approval of all jobs is required. A yellow badge with approved equipment listed must be worn when working in the lab. As an individual progresses through the lab and is safety briefed and trained on individual machines he/she may have unsupervised access to only those machines on which they have been checked and verified. Normal Access (Green) An individual will be awarded a green badge indicating he/she has completed safety checks on all machines and has also been briefed on the current policies concerning lab operations. Prior approval of jobs is not required but drawings or sketches must be present at the work area. Limited TA (Blue) This teaching assistant wears a blue badge and must be thoroughly trained and approved by the shop supervisor. He/she is authorized to open the lab after hours for not more than four students. This person would typically be a member of a project team. The team members would be the only people normally working under this TA s supervision. Unlimited TA (Red) This TA will wear a red badge. He/she is authorized to open the lab after hours. The Unlimited TA is given the authority and responsibility to correct lab activities they consider dangerous to persons or property. Faculty/Staff (White) He/she is authorized to open the shop after hours. The Faculty/Staff member has the authority and responsibility to correct shop activities they consider dangerous to persons or property. This access badge must be displayed while using shop equipment. The safety check and policy review is required every semester. All safety tests and Request for Shop Use forms (PE-002A) must be turned in to the Shop Supervisor s office before semester break. No badges will be issued after semester break. 1

2 2. Students requiring the use of the major machine tools (lathe, mill, grinder, cnc machines, etc.) must sign out for the machines. The student must present his/her access badge to the Shop Supervisor to get a key to the machine and a key to the toolbox assigned to that machine. In times of increased usage, such as when senior projects are due, usage will be limited to three hours at a time, unless special requests are made and can be approved. 3. Students using machines must obey all safety restrictions, either posted or made part of this document. Major restrictions are: * Safety glasses or goggles MUST be worn at all times in the shop area. * Long hair, loose items of clothing, jewelry, etc., shall be constrained so as not to be a hazard near rotating or otherwise moving machinery. * All safety features of the machinery shall be properly utilized. * Exercise extreme care when using compressed air to blow chips off machines. DO NOT use compressed air to blow off clothing or skin. 4. No one is allowed to use machinery alone. If the Instructor is not in the Shop, students are required to work in pairs. This is particularly important when using the machines after normal working hours. 5. The user of a machine shall be responsible for cleaning each machine after use. Cleaning consists of taking all chips off the machine, wiping the machine down with shop cloths, sweeping the floor area, and disposing of all chips and mess created by the user. Making it look like the user was never there. The user is responsible for returning all tools to their appropriate locations. The user is also responsible for returning the machine key and toolbox key to the Shop Instructor. Violation of this rule will get the user suspended from the shop. 6. All tools or equipment taken from the Shop area must be signed out for and returned promptly after completion of the job. 7. The Shop is not a depository for junk. Any project or other material left in the Shop will be discarded, unless special permission is obtained from the Shop Instructor. 8. Students are responsible for their own tooling. Although the Shop contains certain standard tooling (drills, end mills, etc.), as a general rule a student working on a project should be prepared to purchase his/her own tooling, as required. If tooling belonging to the Shop is broken, the student is required to notify the Machine Shop Instructor ASAP. 9. Students are responsible for providing their own materials. Although there is a limited stock of material in the Shop area, it belongs, in general, to specific projects. This stock may only be used with the explicit approval of the Shop Instructor. 10. Students are required to follow all instructions given to them by the Shop Instructor or other authorized individuals. 11. IF IN DOUBT... ASK!!! 12. Any person found misusing the equipment will be subject to disciplinary action. 2

3 After Hours Procedures 1. No students are permitted to operate power tools in the lab alone. 2. Students must display their access badge while they are in the lab 3. After hours, the stock room and many of the tools are secured. Arrangements for access to the required tools and materials should be made with the lab supervisor during normal hours. 4. Students should not remove tools from the lab unless prior arrangements have been made with the lab supervisor. 5. Keys to the machines and toolboxes must be returned by 8:00 am the following morning. Safety Items Following is a list of some of the safety items in the machine shop. This is a partial list only. This does not include all safety issues. General 1. Safety glasses must be worn at all times while in the shop area. 2. Long sleeved shirts or loose clothing should not be worn while running machinery. Moving parts of machinery can catch them. 3. Never wear gloves while operating machinery. 4. Never use rags to hold parts while machining. 5. If you have long hair, you must tie your hair back to keep it out of the way of moving machinery parts. 6. Before you operate a machine make sure that the floor area is clean and dry, make sure the work is securely held, and remove all tools and other items from the machine. 7. It is okay to use shop air to blow off parts and machines, if you use extreme caution. Never use shop air to blow chips or dirt off clothing or hands. 8. Replace or sharpen any tool that becomes dull or chipped. 9. Keep flammable liquids and material away from machines. Flammable liquids and materials should be kept in the explosion proof cabinets when not in use. 10. Always clean chips and dirt off of parts/devises that are going to be mounted together. 11. Cutting oil is for cutting. Lube oil is for lubricating. There is a difference. 12. If you spill oil on the floor, clean it up. 13. Do not do repairs to the machines. If the machine does not run properly, turn it off and contact the shop supervisor Grinders / Sander 1. Do not grind aluminum, brass, wood or plastic on the pedestal grinder. Grind only steel or iron on the pedestal grinder 2. Aluminum, brass, wood, plastic, and steel may be sanded on the belt sander. 3. Quench parts that may become hot in water. DO NOT use gloves or rags to hold parts while grinding or sanding. 4. The tool rest on the pedestal grinder should never be more then 1/8 away from the wheel. Saw 1. Use coolant when running the horizontal saw unless you are cutting wood or other porous material. 3

4 2. The adjustable saw guide for the vertical saw should be as close to the work piece as possible. 3. When sawing steel and thin materials (under 1/8 ), use a fine toothed blade. 4. When sawing aluminum or thick material (over 1/8 ), use a course tooth blade. 5. When sawing round material on the vertical saw, use a vise to hold the work piece. 6. When sawing thin material, use a piece of scrap wood under the piece being cut. 7. Use a pusher block on work pieces that are small. 8. NEVER put your fingers close to the blade while the machine is running. Lathe 1. Turn cams on the cam lock spindle clockwise when mounting chucks. 2. Never leave a chuck wrench in the chuck. Do not take your hand off the chuck wrench until the wrench is out of the chuck. 3. Do not stop the spindle by hand. Let the chuck coast to a stop or use the brake. 4. Always wipe off chips and dirt from mating surfaces when you change chucks, collets, drill chucks, centers, tool holders or any other mating parts. Mounting tooling with chips present can cause permanent damage. 5. When removing chucks from the lathe, place a board across the ways. This prevents possible damage to the ways. If the chuck is stuck after loosing the cams, rap briskly with a SOFT FACE hammer. 6. Before turning on the spindle, make note of all pinch points, remove tools from working area and disengage power feeds. 7. While sanding or filing in the lathe, keep your left hand toward you and your right hand to the back of the machine. Never sand or file with your body over the spinning chuck. 8. Remove stringy chips with pliers while the spindle is off. Never remove stringy chips while the spindle is rotating. Never remove stringy chips with your hands. Chips can have razor-sharp edges. 9. DO NOT use parting tools as turning tools. Mill / Drill Press 1. Make note of all pinch points before tuning on the spindle. 2. Never stop the spindle by hand. Let it coast to a stop or use the brake. 3. Never take your hand off the draw bar wrench until the wrench is removed from the draw bar. NEVER LEAVE THE WRENCH ON THE DRAW BAR. 4. Never leave a drill chuck key in the chuck in the tightening position. Always remove the chuck key after tightening the chuck. When storing the chuck, place the handle of the key in the chuck. 5. Most of the time the spindle will be run clockwise (looking down from the top). Because some tools were made to run counter-clockwise, spindle rotation will be determined by the cutter design. 6. Clean dirt and chips from mating parts when changing cutters, collets, drill chucks, vises, rotary tables, or any other devise. 7. DO NOT mill with a milling cutter in the Drill Chuck. Unsafe practice or obvious abuse of equipment constitutes a danger to people and damages equipment. Therefore the lab supervisor will stop unsafe practice in the lab. Students violating any of these rules will have their Shop privileges revoked for a period of at least two weeks. Longer periods may be assessed, depending upon the judgment of the Shop Instructor and the Precision Engineering Laboratory Director. 4

5 Variable Speed Drives There are four types of machine drives in common use, mechanical variable speed, electrical variable speed, gear drive and step pulley drives. Mechanical Variable Speed Drive. Mechanical variable speed drives commonly use two adjustable width pulleys, one spring loaded and the other adjusted by the operator. A typical example is the system used on Bridgeport style milling machines and the variable speed mechanism on the vertical bandsaw. The operator adjustable pulley is mounted on the tool spindle in the front, and the spring loaded pulley is mounted to the motor in the rear, with a pulley belt connecting them. When the operator closes the width on the spindle pulley, it pulls the belt forward, forcing the motor pulley open against the spring. When the operator opens the width of the front pulley, the spring pushes the back pulley closed, drawing the belt back. This type of drive must be adjusted while the motor is running, to allow the belt to walk back and forth as the pulleys are adjusted. Electrical Variable Speed Drive. Electrical variable speed drives use DC motors with adjustable voltage supplies, or AC motors with control circuits that adjust the frequency of the AC current to control the speed. With either type, the speed can be adjusted while the machine is running or while it is stopped, whichever is more convenient. In the shop an example of this type of drive is the variable speed on the Smithy machines. Gear Drive. Gear drive machines use physical gears to drive the machine spindle. The engine lathes in the shop are all gear driven, except for the Hardinge. These machines do not have clutches, so they must be stopped to change gears. And care must be taken to ensure that the gears are fully engaged before re-starting the spindle. Step Pulley Drive. Step pulley drives use pulleys with various diameter grooves for the belt, from two to four different diameters on each pulley, to change the proportional speed between the machine spindle and the motor. To adjust the speed, the operator stops the machine, loosens the tension on the belt, and uses his hands to move the belt to an alternate pair of steps on the pulleys. Make sure that the power is off before adjusting this type of drive. An example in the shop is the high/low speed selection on the Smithy machines. 5