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Open-end, box-end, standard, metric, socket, ratcheting box-end, offset, universal or flare-nut? The myriad of wrenches that are available may seem confusing at first, but a quick lesson will prepare you to select the best wrench for almost any job.
For regular, fixed-jaw wrenches, some mechanics prefer the open-end variety, while others prefer the ring or box-end style. Since each offers certain advantages in specific applications, the best-equipped mechanics have a set of each. One alternative is to purchase a set of combination wrenches and get the best of both worlds.
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One of the more common frustrations for the novice do-it-yourselfer (automotive or otherwise) is being without a necessary tool to complete a particular job. And one of the variations on Murphy's law dictates that this circumstance will always present itself when you're halfway through a project -- with parts and tools strewn all over your garage or workshop floor. Almost as bad as not having the proper tool is realizing, during your emergency trip to the hardware store, that you don't know the exact name of the tool you need to purchase. Or the size, or whether it's standard or metric, or whether you need galvanized or chrome, or -- you get the idea. Getting into the habit of exercising some forethought about what tools you'll need to take on a given project, and being armed with some precise tools-terminology, does a surprising amount toward bolstering your confidence and comfort-level. Imagine the satisfaction you'll feel by walking up to a salesperson and stating emphatically, "I need a 12-inch carbide-tipped blade for a sliding compound miter saw and a set of metric 8-point sockets with quarter-inch drive." It's rewarding to be able to "talk the talk." Moreover, a genuine understanding of a wide range of tools is one of the hallmarks of a competent do-it-yourselfer. When it comes to automotive mechanics, the logical place to start learning about tools is with wrenches. Wrenches are the mainstay of the mechanic's arsenal, and if you're serious about your do-it-yourself pursuits, it's wise to invest in quality wrenches. High-quality wrenches last for years without wearing out, while ones of lesser quality tend to wear, slip and damage the components and fasteners on which they're being used. The common feature of the mechanic's wrenches is that they are used for turning nuts, bolts or other square or flat-sided objects. (In contrast to plumber's wrenches or pipe wrenches that have teeth so that they can also grip round objects.) A broad variety of wrenches are commonly available, some of which are designed for very specialized applications. One of the most common household tools is an adjustable wrench, sometimes known as a monkey wrench figure A). These versatile wrenches come in various sizes, and their distinctive characteristic is a movable jaw that can be adjusted to fit a variety of sizes of nuts or bolts with a simple adjustment screw. For light-duty automotive jobs, they can be useful in a variety of applications. Some are made with short or "stubby" handles for use in tight spaces. For more critical work, however, it's wise to use a fixed-size wrench, such as the open-end or box-end varieties (figure B), rather than an adjustable wrench. Open-end wrenches have narrow, steel handles, fixed-size jaws (figure B, left) and are designed specifically for tightening and loosening bolts -- especially those accessible from the side. They tend to be easier to use in tight spaces than an adjustable wrench. The length of the wrench-handle is proportional to the size of the jaws, with larger sizes having longer handles for added leverage. (Short-handled versions are also available for specialized uses.) Wrenches come in a range of jaw-sizes, and each wrench is named according to the size nut it will fit. They are typically sold in sets of metric or standard (inches and inch-fraction) sizes. Those that have an open jaw on each end of the handle (usually in two consecutive sizes, such as 1/8" and 5/16") are referred to as the double-end style. Those that have jaws that are angled slightly from the plane of the handle are referred to as offset wrenches, and are designed to give better access into tight, awkward spots. Box-end wrenches, sometimes called ring wrenches (figure B, right), also have long, steel handles, but instead of an open end, have a closed ring with interior points or "teeth" designed to grip the facets of particular sized nut or bolt. There may be either six points or twelve points on the box interior (figure C). The box-end varieties shares many of the characteristics of the open-end wrenches, but are preferred by some mechanics since, in some circumstances the closed end may prevent the wrench from slipping off the nut. Just like the open-end variety, box-end wrenches are available in double-end and offset styles. Combination wrenches, as the name implies, have an open jaw on one end of their handle and box end on the other -- with the two ends generally fitting the same sized nut. Combination wrenches are considered desirable since their combination of benefits makes them very versatile. Combination wrenches are also available in straight or offset styles. Socket wrenches, also known as ratchet wrenches, can ease your workload considerably. They are designed with a long steel handle topped with a head that contains reversible ratchet mechanism and a square peg or drive. Interchangeable sockets, accommodating different sizes of nuts, are seated on the drive. Once the appropriate sized socket is attached, the socket-wrench can be used to loosen or tighten a nut or bolt very quickly, and with less effort than with a regular wrench. This is because the ratchet mechanism allows the handle to move in two directions -- one direction for effort (loosening or tightening) and then effortlessly back in the other direction. In this way, the wrench does not need to be removed from the nut, then re-seated, with each turn. The base of each socket is equipped with a spring mechanism that holds firmly to the drive. In addition, the ratchet mechanism has a reversing lever, allowing the wrench to be used for tightening or loosening without having to change the orientation of the wrench. Like box-end wrenches, the sockets themselves may be either the six- or twelve-point variety (figure D). Socket wrenches are useful for tightening or loosening nuts or bolts that are accessible from their end, and are adaptable for use in a variety of tight spaces. Socket sets often include accessories such as extenders and adapters that further enhance access in certain situations and allow use of a broader range of sockets. There are also specialized sockets for installing and removing spark plugs. Taking adaptability even further, universal sockets, also known as flex-joints or flexible heads (figure E), rotate allowing the socket to reach in at angles to reach particularly difficult locations. Ratcheting box-wrenches combine features of the socket and box-end wrenches. Though most are equipped with a thinner, flatter handle, they are essentially a box-end wrench equipped with a ratcheting mechanism (figure F). To reverse the ratcheting action (i.e., to switch from tightening to loosening, or vice versa), the wrench simply needs to be turned over. Some are actually etched with the words "on" and "off" to make it simple to discern whether the orientation will result in tightening or loosening. Like ordinary box wrenches, these are available in straight or offset styles. Flare-nut wrenches, also known as flare wrenches or line wrenches (figure G), are similar to regular open-end wrenches but feature more facets to allow better grip. In contrast to a regular open-end, in which only two sides of the jaw will be in contact with the nut, the flare wrench offers more efficient turning power. In applications where nuts or bolts are very tight, difficult to access or made of softer metal, use of a flare wrench may prevent marring or rounding the head of the fastener. Wrench-usage tip: In some circumstances -- such as loosening a motor mount (figure H) -- it may be necessary to hold a nut stationary while loosening the bolt that is attached to it. In this instance, it's often best to use two wrenches, rotating in opposing directions, to break the bolt free. Simply reverse the process to install and tighten a nut-and-bolt combination. Using a ratchet wrench in combination with an open-end or box-end will make the job go even quicker and easier. One of the most important tools for automotive work is the torque wrench, a highly specialized socket wrench designed to tighten a nut or bolt to a particular degree. With many engine parts -- and even in other mechanical applications such as on lug nuts when changing a tire (figure I) -- there are cases where overtightening or undertightening a particular bolt can result in damage or eventual mechanical failure. In such cases printed torque specifications, found in the vehicle's owner manual or service manual (figure J), will tell you numerically how far the bolt needs to be tightened. The torque wrench allows you to install the fastener to that exact specification. A rotating handle, and markings etched on the shaft of the wrench (figure K), allows you to dial in a particular torque spec. Once the torque is set, the torque wrench is used much like an ordinary socket wrench. An audible click tells you exactly when to stop tightening. This results in the fastener being tightened to the precise pre-set amount. Note: With some torque wrenches, the stop-point is denoted by a second click. Follow the instructions that come with your particular wrench.
RESOURCES :
Auto Repair for Dummies
Author: Deanna Sclar
ISBN: 0764550896
Some vehicles provided by Beaty Chevrolet
Beaty Chevrolet
9615 Parkside Drive
Knoxville, TN 37922
Phone: 865-693-7712
Web site: beatychevrolet.com
Some vehicles provided by Ted Russell Ford
Ted Russell Ford
8551 Kingston Pike
Knoxville, TN 37919
Phone: 865-693-7611
Web site: www.tedrussell.com
The Haynes Automotive Tools Manual : The Haynes Manual for Buying and Using Automotive Tools
Model: 1563921073
Author: Eric Godfrey and John H. Haynes
(1994)
To order this title from Amazon.com, click here.
Haynes Publications
The Complete Illustrated Guide to Everything Sold in Hardware Stores
by Steve Ettlinger
(revised edition 1998, Macmillan)
To order this book from Amazon.com, click here.
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