Portland Community College | Portland, Oregon

Turning Machines & Operations consists of the following modules:

Maintaining the Lathe - The lathe is one of the most important and most versatile machine tools. This module will introduce the student to the lathe, its basic parts, its accessories, lathe safety procedures, and lathe maintenance.

Aligning Lathe Centers - To machine a parallel diameter on work mounted between centers, it is important that the headstock and tailstock centers be in a straight line and true to the centerline of the lathe. If the centers are not aligned, the diameter of the work piece being turned will be tapered. In this module, the student will learn how to align the centers of the lathe using the trial cut method.

Facing on the Lathe - Facing is one of the first operations usually performed on the lathe. It is the operation of machining the ends of your work piece square to the axis. Facing is also done to machine your stock to the proper length. In this module, the student will learn how to face the ends of a work piece to a specified length.

Parallel Turning / Filing - Turning is the most common machine process done on the lathe. Through this process, a revolving work piece is cut with a stationary cutting tool that is fed longitudinally along the work. In this module, the student will learn to turn work on the lathe to "rough" and "finish" quality.

Grooving & Parting - A work piece, after it has been machined, is sometimes cut off on the lathe. The tools used, commonly called cut-off or grooving tools, can also be used to cut grooves and for undercutting. In this module, the student will learn to cut grooves and cut off stock on the lathe.

Cutting Radii & External Tapers - The taper attachment method of machining a taper on the lathe has several advantages over other methods. For example, long tapers may be machined more accurately and the lathe centers remain aligned. In this module, the student will learn to machine an external taper using the taper attachment.

Knurling - Knurling is the process of rolling depressions into the surface of a piece of metal. The knurling tool has hardened steel wheels on which a design is cut. As the wheels revolve against the work piece, the rollers transfer the design to the work piece. Knurling is done to provide a good gripping surface on tools to be adjusted by hand, or to improve their appearance. In this module, the student will learn how to knurl on the lathe.  

The student will be able to turn safely and accurately an exercise piece to print specifications using many of the set-up and various turning operations associated with the lathe.     

PREREQUISITE SKILLS AND KNOWLEDGE:  
MCH 125  

This course is based on performance outcomes. The following performance outcomes are based upon established industry standards. The student will demonstrate knowledge and understanding through the following activities:  

• Given operation manuals for the lathes, and necessary materials and equipment, lubricate a lathe to manual specifications, check level of lathe and concentricity of three-jaw chuck with test indicator and align lathe centers by adjusting the tail stock.
• Safely and accurately face and center-drill both ends of the work piece on a lathe;
• Rough and finish turn the work piece according to print specifications;
• Groove and part the work piece to print specifications;
• Machine an external taper, a radius, and chamfers on the work piece;
• Knurl the work piece to print specifications.  

MCH 180 will be presented by means of audio-visual presentations, demonstrations, lab experiences, and research activities. The course activities and design emphasize the development of skills and knowledge outcomes prescribed by established industry standards. The identified outcomes will be achieved by means of individual and team activities.  

POLICY - Student performance measurements are based on established industry standards. The various areas of study during the course will be evaluated by a variety of activities. Typical of those activities are the following;

1. READING ASSIGNMENTS - Information sheets, textbooks, journal articles and the learning resource center are potential sources of information that the student will reference as directed in the modules identified in the introduction. 

2. PRACTICE - Completion of tasks and projects identified in the reading assignments, information sheets, journal articles and textbooks. Students are required to complete practice activities with 100% competency.

3. SELF-ASSESSMENT - Checking and evaluating the students understanding and knowledge gained through the reading assignments and practices typically done through a practice evaluation.

4. LAB ACTIVITIES - Participation in structured laboratory exercises with the emphasis on developing skills or increasing expertise in the areas of study identified in the module packets.

5. FINAL ASSESSMENT - An assessment in the form of a written exam and/or practical application that addresses the subject areas identified in the module packets. Students are required to complete final assessment activities with 85% competency.

TEXT:  

Machinery's Handbook

Technology of Machine Tools by Krar, Oswald, and St.Amand

Machine Tool Practices, by Kibbe, Neely, Meyer, and White