A Guide To Impact Wrenches

Pneumatic wrenches, along with hydraulic and electric impact wrenches are one of the most used tools in a workshop, by both amateurs and professionals alike. They are used to tighten bolts to the correct torque, and loosen them, and are one of the biggest labour savers in the workshop. All styles work in the same way, by spinning a mass to a high speed and then engaging a clutch to deliver the torque in a quick burst. Of the different types, air impact wrenches are the most popular.

Air impact wrenches are by far the most popular in most workshops, but that is largely due to the fact that most automotive workshops have a large compressor and a full compliment of air tools. If you don’t already have a suitable compressor, and don’t have a need for one, then an air impact wrench might not be your best option. Similarly many commercial workshops will have 1″ and 2″ drives, but do you really need that for working on the family car? We’ll answer those questions and more, so let’s start by considering your choice of power source.

While air powered wrenches are the most popular, they might not be the best choice for the small home workshop. Since they use compressed air as their power source, you’ll need a high power compressor to run one, which can be a considerable extra expense if you don’t already have one. For a home workshop, where an impact wrench will only be used on occasion, a mains powered or cordless wrench is probably more suitable. With modern batteries, a cordless wrench is quite powerful enough for most work and they are quite reasonably priced, especially when you consider that you don’t also need to purchase a compressor.

The next consideration is what size of drive and sockets you’ll be needing. This will be influenced by what you’ll be using the wrench for, and whether you already have some sockets. In general, the heavier the work is the larger drive you’ll need. 1/2″ sockets are quite suitable for working on most cards, with 1″ or even 2″ being needed if you’ll be working on commercial or plant vehicles. Drive sizes over 2″ are normally only used in heavy industrial workshops.

There is one other choice to me made, and that is style. The smallest wrenches are shaped like a screwdriver, but they are only capable of delivering low torque. Most 1/2″ wrenches are of the “pistol grip” variety, shaped like an electric hand drill. As you move up to heavier duty tools you’ll start to come across D and T grips which allow for a much firmer hold, and so much higher torque levels. The correct style for you will depend on the type of work you’ll be doing, so take that into consideration when making a purchase.

Once you have decided on a power source, socket size and style it’s time to hit the stores. Good quality wrenches are made by a number of suppliers such as Ingersol, Draper, Sealy, Makita and more. Shop around for a good deal, and be sure to check out the online stores as there are real bargains to be had!

For more information about impact wrenches visit impact wrench guide