A mechanism description paper analyzes the appearance, function and operation of an object. The most difficult hurdle in writing a mechanism description is staying on topic without persuading the reader about the object's value. The paper is meant to present the facts about an object in an objective manner that allows the reader to make his own value judgment. Moreover, the amount of detail you include depends on your audience. If you know your audience and write objectively, writing a mechanical description paper is relatively straightforward.
Write an introduction that outlines the purpose and scope of the description paper. Devote only a few short sentences to this and only write an entire stand-alone paragraph if your paper exceeds two to three paragraphs in length. If the introduction needs to be a stand-alone paragraph, briefly describe the appearance of the object and define its function and operation. Avoid making grand statements in the introduction like, "throughout the ages." Do not attempt to impress your reader by providing unnecessary information and background history of the object of study; only provide accurate and direct information as efficiently as possible.
Dedicate the next portion of the essay to describing and defining the object's mechanical function. Answer the question, "What does it do?" Briefly describe the process in which it participates, if the object is only a part of a large process. Provide background information on the function of the object only if the object is completely unfamiliar to your readers.
Dedicate the next section of the description paper to appearance. Answer the question, "What does it look like?" Break up and categorize all of the object's components into classifications and describe them in an organized sequence. For example, describe the outside features first and the internal features second. Use a bulleted list if you need to break your object into more than three component classifications. Dedicate as much space to this as is necessary to provide a detailed description of the object's appearance.
Dedicate the final section of the description paper to operation. Answer the question, "How does it work?" Use this section of the paper as the conclusion. Avoid conclusive words like "therefore" and "finally." Write instead a direct answer to the above question. Explain how the design helps the object achieve its operative function. Dedicate a few sentences to a paragraph for this section.