Wrenches are useful tools that tighten and loosen nuts and bolts on furniture, cars, electronic devices, and many other objects. These tools often appear in wrench sets that consist of various styles and sizes that work with different types of nuts and bolts. Although they are simple tools, buyers that want to choose the right wrench for the job need to understand how they work and the different types of tools available.
How wrenches work
The opening on a wrench is slightly larger than the nuts and bolts it fits, so users must select the appropriate size of tool for the task. To use a wrench, a person places the wrench opening over or around the head of the nut. Turning the wrench to the left loosens the nut and turning it to the right tightens it. If the wrench opening does not fit the nut, the user risks stripping the head, which damages the nut and renders it useless.
Types of wrenches
There is a variety of wrenches with different types of designs that make them useful for particular tasks. They need to have shapes that match the heads of the nuts or bolts they are installing or removing. Some wrenches, such as pipe wrenches or oil wrenches, serve only one purpose, while others work in several scenarios.
Adjustable wrenches have expandable heads and a worm screw that adjusts the size of the opening to fit the nut or bolt. As these wrenches do not have predetermined sizes, they work with nuts and bolts of any dimension, including metric and Whitworth. Two common types of adjustable wrenches are crescent and monkey wrenches.
Box-end wrenches have closed ends that form a ring shape and contain six to 12 points along the inside diameter that help to grip the nut or bolt. Some of these wrenches also have ratchets inside for quick turning. Many users find that box-end wrenches grip nuts and bolts more firmly than open-end wrenches and fit better in tight spaces.
Open-end wrenches have flat jaws designed to slide around nuts and bolts. The open end comes in handy in situations when there is not enough space to slide a box-end around the entire nut. Levered for loosening and tightening, these wrenches are quick and easy to use for a variety of projects.
Combination wrenches offer the best of both worlds with a closed box-end on one side and an open-end at the other. These tools are handy because users do not have to buy two sets of wrenches to complete a job.
Sockets are metal cylinders that fit completely over nuts and bolts. Most sockets work with ratchet handles that allow users to tighten or loosen nuts without removing the sockets to speed up the work process. Sockets work well in tight spaces that do not allow users much horizontal movement.
Allen keys, also called hex keys because of their hexagonal shape, are L-shaped pieces of steel. Users insert either end into the matching opening of hex bolts and turn to tighten or loosen them. People use Allen keys frequently when working with furniture and electronic devices.
Choosing the right wrench
Before selecting wrenches, users must inspect the heads of the nuts or bolts and determine their shapes. While doing this, they should also evaluate how much space is around them. They then select a wrench and try to slide it in place over a nut. When the end slides easily around the head and grips it sufficiently, this is the right wrench. Finally, users must choose the right handle length for the job, bearing in mind that short handles reduce the amount of force needed to turn the wrench, while long handles increase the turning force.
How to buy wrenches on eBay
Shopping on eBay is a great way to find the wrenches you need for your toolbox. To discover the available items, enter a descriptive phrase, such as "socket set" or "ratchet wrench", in the search box on any page. As you look through the listings, pay attention to details such as the wrench's measurement system and condition so you know whether the tool meets your requirements. At the same time consider buying additional nuts and bolts so you have spare pieces in case you need them.