TABLE OF CONTENTS Several terms used with machine parts may need clarification. There are also several different types of holes that may not be familiar to the reader. The purpose of this chapter is to examine some of the machine terms and holes that may not be clear. This review will provide a better understanding of the items and their purpose. The items will then be easier to visualize and have greater meaning when they are seen on a print.
Some of the terms may have different meanings when related to other subjects. Terms such as burr, chamfer, and broach have specific meanings when used with machine parts. The term feature is often used as a general reference to all machine terms and holes. A note may state general tolerances apply to all features that do not have specific tolerances.
Many of the terms that are used with machine parts may not be specified directly on the drawing of a part. As an example, a title block note may state that all fillets have a 0.250 in. radius, unless otherwise specified. The drawing may show a fillet, but it may not have a direct reference or dimension. In mis example, the term fillet must be known in order to understand the drawing. Another example is the term draft. A note may state that all draft are 5 1 , unless otherwise specified. A drawing may or may not show surfaces with drafts. Unless the term draft is understood,...
