Portland Community College | Portland, Oregon

Basic Measuring Tools consists of the following modules:

Machinist Scale / Dividers - Every part produced in the machine shop must be measured in some way. The machinist's scale (rule) is used for rough measurements and laying out work pieces for machining. In this module, the student will develop your skill in the use of the scale. Dividers are a measuring device even though they have no scales to read. One of the important uses of the dividers is transferring measurements from a drawing to the work piece. Because of the methods used to reproduce drawings, machinist's scale or the dividers cannot be used directly on the drawing. Instead, the machinist must read the dimensions on the drawing, set the dividers to that measurement to the work piece. In this module, the student will learn to transfer measurements from the scale to the work piece.

Telescoping Gage - How to measure holes accurately is one of the many skills the machinist must learn. There are several different methods and tools that can be used to perform this operation. The telescoping gage is one of these tools. In this module, the student will learn to use the telescoping gage to determine the diameters of holes.

Combination Square / Hermaphrodite Calipers - In this module, the student will learn to use a set of tools called the combination square set to scribe angles and straight lines on a piece of metal and how to layout the center of a piece of round stock. In this module, the student will learn to use the hermaphrodite caliper to scribe parallel lines and find the center of round stock.

Surface Gage / Identifying Surface Finishes - Machinists must sometimes scribe lines on a vertical surface. In this module, the student will learn how to scribe such lines with the surface gage. Much consideration must be given to surface smoothness wherever two machined surfaces come into contact with each other. This module will help the student identify factors that contribute to the quality of surface finish, and give practice in identifying surface finishes.  

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

• Lay out work pieces accurately using the proper transfer measuring tools.
• Accurately measure the inside diameter of a hole using a telescoping gage.
• Identify various machined surface finishes.

The student will be able to transfer various dimensions from blueprints to a work piece by using the correct measuring tool; will be able to measure hole diameters accurately; and will be able to recognize the difference between machined surface finishes.

MCH 135 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