They are an essential tool in your toolbox and are used to tighten and loosen nuts, bolts, screws and pipes. Below we look at the most common types of spanners and how to use them.

General spanner guidelines

Choose the right spanner size for the job. To avoid damage to your fastener or yourself, always choose a spanner that matches the fastener you are tightening or loosening. Also, make sure the jaws of your spanner are fully in contact with the fastener before applying pressure. These two things will go a long way to ensuring that your spanner doesn't slip and you swear over an injured knuckle.

Pull, don't push. When using a spanner, you usually want to position yourself to pull it rather than push it. This will ensure that you don't bark a knuckle if the spanner slips off the fastener. If you have to push a spanner, use the heel of your hand to keep the spanner from slipping.

Do not add more leverage with the pipe. You may have seen your father put a longer piece of pipe over his spanner to add leverage when tightening a fastener. You should avoid using "cheater bars" for several reasons. First, they can damage your spanner by bending the handle or jacking up the head. Secondly, because of the extra torque you get with the extra leverage, you risk rounding your fastener if you don't have the right spanner head for the job. Finally, there is the possibility that the cheater bar will slip off the handle of the spanner as you turn it and cause damage to you or others. If you need more leverage, use a longer spanner. If you have a particularly stubborn lock, apply some penetrating oil (like Liquid Wrench) to the thread, wait a few minutes and then try to get loose.

Don't hit a spanner with a hammer. Unless you have a special "impact" spanner designed to be hit with an object, don't take a hammer to your spanner to get more force to turn a stubborn fastener. You risk damaging your spanner.

Do not use a damaged spanner. If the handle is bent or the jaws are wider than they should be, don't use them.

Buy quality spanners. Good spanners last longer; cheap spanners slip more easily. Personally, I'm a craftsman's fan. They have a lifetime warranty on all their hand tools. If a spanner ever bends or breaks, you can pick up a Sears or Ace and they will replace it for free, no questions asked (some sales people might tell you something). I have no affiliation with Craftsman whatsoever - it's just what I use.

Types of spanners and how to use them

This should be your first spanner you buy when you are just starting your tool collection - one large and one small. An adjustable spanner has a fixed jaw and an adjustable jaw that allows you to use it for a variety of fastener sizes. The jaws are typically smooth and flat and designed to grip square and hex nuts. The head of a crescent spanner is typically angled 22 1/2 degrees to the handle, allowing the spanner to be reversed to provide two different grip positions in tight spaces.

How to use a Crescent Wrench

While a crescent spanner is designed to allow you to apply pressure to both the fixed and movable jaws, ideally most of your work should be done so that pressure is only applied to the stronger, fixed jaw. Too much pressure on the weaker, adjustable jaw can cause the spanner to break and you to bark a knuckle. When you put the spanner on your nut, the adjustable jaw should be on the side you want the rotation to be. This puts pressure on the fixed jaw.

Open the spanner

An open-end spanner is a non-adjustable spanner that comes in a variety of sizes. You usually buy them in sets (both metric and standard SAE sizes), although you can buy them individually if you like. There are a few advantages that open-ended spanners offer over adjustable spanners. Firstly, because both jaws are fixed, you don't have to worry about breaking an adjustable jaw. Secondly, they are very handy when you are tightening and loosening a few nuts and bolts of the same size as you don't have to readjust anything when you tighten spanners. Makes tightening and loosening much faster than with an adjustable spanner.