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Choosing the right spanner

Shop for Spanners

Spanner size is very important when choosing your spanner but there are other things to consider too. There are a number of things that need to be taken into account when choosing the right spanner for a task. Along with the obvious choice of spanner size (see What spanner sizes are available?), there are a few other things to consider.
Long spanners are better for larger or stiffer nuts, bolts and fasteners than short spanners. The length of the spanner makes a difference to how much force can be applied to the fastener. Longer spanners create greater torque (turning force) so are better for larger or stiffer fasteners.
Different ways the spanner fits onto the fastener nut creates different stabilities. The profile of the spanner affects the stability of the connection between the spanner and fastener. Profiles that make greater contact with the fastener (such as box spanners) are less likely to slip from the fastener than spanners that only contact a few sides of the fastener (such as open-ended spanners). However, they may not be so versatile.
Jaw thickness and depth of the head changes the strength of the spanner. The thicker and wider the head of the spanner, the stronger it will be. Thick heads and shafts strengthen the whole spanner and provide more contact with the fastener which means the fastener will take less effort to turn and is less likely to get damaged in the process. On the other hand, wide heads don’t fit into small spaces.
Vanadium is used to make chrome vanadium alloy steel for spanners but is very expensive. The material the spanner is made of significantly affects the quality of the tool. Tools made from titanium or from steel with a high percentage of vanadium (up to 1%) are the highest quality on the market and could easily last a lifetime. See What are spanners made of? for more information.
Wonkee Donkee says: But don’t worry too much, if you only need a few spanners for your DIY projects your best bet is a set of standard combination spanners from the local shop.