Wrench Sets
Posted on 25. Jan, 2012 by Auto Mack in Posts, Tools, Wrench Topics, Wrenches
What is a wrench set?
Bolts come in many sizes and can be in all sorts of places, so wrenches must also come in many sizes to fit them and many shapes to reach them. A wrench set provides buyers with several sizes of wrenches that all share one wrench design letting the user perform one type of job on a wide range of bolts.
In most cases a wrench set will have wrenches sized between 8mm or 3/8″ and19mm or 7/8″. Wrench sets outside these ranges are generally labeled “miniature” or “large.” Some specialty wrench sets will be designed with a few commonly used sizes.
Wrench sets are sold by head and handle design. This can be a little confusing as the same tool design can have multiple names.
Wrench Types
Universal, combination, and box end wrenches: All three names are used to describe a wrench with one box end and one open end. This is by far the most popular type of wrench.
Open-end wrench: Both ends of the handle have open-end heads. Most open-end wrenches have two different sized ends. These are typically two sizes apart as some manufacturers make nuts that are one size away from the bolt they are on. This ensures you will always have two wrenches that will work on a single nut/bolt combo.
Ratchet wrench: This name can refer to a ratcheting handle used with sockets or a stand-alone tool. This later type of wrench has an internal ratcheting mechanism allows the inside of the wrench head to turn, letting it move the bolt or nut without having to be taken off and rejoined with each turn. The ends completely surround the bolt like a box-end wrench, and like open-end wrenches they will often have two ends of different sizes on a single wrench.
Line and flare nut wrenches: These look like box-end wrenches except they have a small slot at the top of the head to let the wrench pass through metal lines. These are mostly used on brass fittings where even a slight increase in surface contact with the bolt head can mean the difference between a turned bolt and a stripped one.
Adjustable wrench: These have adjustable jaws that are moved in and out using a worm gear or small motor. Three or four of these wrenches can replace an entire set of fixed-size wrenches, but they’re exterior size limits where they can be used.
Hammer, striking, and slugging wrenches: One end has an anvil designed for striking while the other end is either an open or box-end wrench. They can be useful for loosening very tight bolts.
Cone wrenches: These flat wrenches are used almost exclusively on bicycles. They are designed to turn the axle cones while the wheel is still bolted to the frame.
Handle Types
Offset: The end of the wrench is bent so that when it’s placed on a bolt the handle sticks out away from the bolt instead of in line with it. The box-end of a combination wrench is normally offset.
Crow foot: An open-end wrench head with a square hole for a socket wrench. This functions as a 90-degree offset wrench.
Half-moon and “S” handles: The handle has one or two bows to allow the heads to reach around objects like starters and water pumps.