Impact Wrenches

Yes, a cordless impact wrench can be used for heavy-duty work, such as automotive tasks, steel assembly and maintenance work. 

Modern cordless impact wrenches can deliver up to 3000Nm, which is ample for most jobs, and rivals most pneumatic impact wrenches for torque output. However, cordless impact wrenches require rechargeable batteries to function, which makes them ideal for work in remote locations, but batteries will eventually run out, causing some downtime, which is why we recommend using batteries rated at 5Ah or higher to ensure longer run times.

In comparison, air-powered impact wrenches run on compressed air and are less prone to overheating if used for prolonged periods. In addition, they are lighter because there are fewer internal components and no heavy battery attached to the tool, which makes them easier for the operator to use over longer periods.

Yes, impact wrenches can be used at home for various DIY projects, especially for tasks that involve bolts and nuts that require enhanced torque, such as changing the wheel on a car, lawnmower maintenance or loosening bolts on joists.

Cordless impact wrenches are probably the most suitable for home use because the batteries can easily be charged and it means that there is no need to store compressed air in the property.

In most instances, there is no need for industrial, high-torque tooling around the home, so an impact wrench with around 400Nm of torque is likely to be able to handle most tasks.

Always ensure there is a spare battery, so that there is only minimal downtime when one battery runs out and needs recharging. 

There are numerous accessories that can work with an impact wrench, including -

• Impact sockets are an essential accessory because the socket grips the fastener and connects to the anvil of the impact wrench. This type of socket is designed to handle the shock and vibration generated by an impact wrench and is manufactured from chrome molybdenum steel, which is more pliable than chrome vanadium that standard sockets are manufactured from.
• Socket extensions are used to reach recessed or hard-to-access fasteners, however, ensure they are impact-rated to prevent breakage.
• Universal joint (U-joint) sockets allow access to bolts at angles, which makes them useful when accessing fasteners in tight or awkward spaces.
• Impact bit holders and hex adapters enable the operator to use screwdriver bits or drill bits for lighter fastening tasks.
• Protective boots protect the impact wrench from grease and other substances it may come into contact with. 
• Spare batteries. We always recommend having a spare battery that is charged and ready to go, to prevent any downtime when the other battery runs out in a cordless impact wrench.
• Impact adapters enable the operator to change the anvil size to fit a different socket drive size.

Yes, impact wrenches are commonly used in automotive settings for tasks such as removing and tightening wheel lug nuts, loosening rusted or seized bolts and working on suspension components.

Impact wrenches are widely used in the automotive sector due to their enhanced torque output, which means that operators can loosen bolts quicker than with hand tools. However, most bolts in automobiles should be tightened to a specific torque measurement and whilst impact wrenches can tighten fasteners, we strongly recommend using a torque wrench to ensure that the fastener is tightened exactly to the manufacturer's torque recommendation. 

Many modern impact wrenches feature variable speed controls, allowing the operator to adjust torque output depending on the task, which helps improve precision, avoid over-tightening and reduce wear on components. Variable speed on an impact wrench is usually controlled by two methods -

1. The trigger, with the operator pressing lightly for lower speed and harder for full speed.
2. Electronic settings on the impact wrench, which enable the operator to select the speed the anvil rotates at.

Socket size depends on the fastener being used and it should match the bolt diameter and type, so a 17mm impact socket would match a 17mm fastener.

The drive size of the socket should always match the drive size of the impact wrench, so a 1/2" impact socket would fit on the anvil of a 1/2" impact wrench.

If we take the above two measurements of 17mm x 1/2" impact socket, it means that the socket fits on 17mm fasteners and attaches to a 1/2" impact wrench.

Only impact-rated sockets should be used with an impact wrench because they are designed to withstand the twisting force and hammering produced by these tools without cracking. Impact sockets are available from 1/4" drive size, all the way up to 1-1/2", and the general rule of thumb is that the smaller the drive size, the less torque the socket can handle. For example, a 1/4" impact socket would be used for light-duty loosening jobs, whereas a 1-1/2" impact socket would be used for industrial applications, such as removing heavy lug nuts on large machinery, like a truck or tractor.

The torque rating on an impact wrench refers to the amount of rotational force it can generate to tighten or loosen fasteners and is measured in Newton metres (Nm) or foot-pounds (ft-lb).

Impact wrench torque is usually measured in two ways -

• Break-away torque (also known as nut-busting torque), which is a higher force used to loosen seized fasteners.
• Fastening torque, which is the force used to tighten bolts.

The operator should always be cautious about the level of torque applied to a fastener and always adhere to the manufacturer's guidelines. If too much torque is applied to a fastener then it can strip threads and potentially damage components that are being fastened to. If too little torque is applied, then fasteners may not be properly secured. 

When fastening bolts, always finish with a torque wrench to ensure precise final tightening.

Yes, an impact wrench can be used to both tighten and loosen a fastener.

Impact wrenches are ideal power tools for loosening seized or stuck fasteners quickly, with the hammering action transferring high levels of torque to the fastener without affecting the operator's wrists. When using the tool to tighten fasteners, the operator should exercise caution because impact wrenches can apply high levels of torque very quickly, which can make it easy to over-tighten fasteners, damaging their threads and the components that they are being fastened to.

An impact wrench has a hammering mechanism so that it can deliver high levels of torque in a series of short and powerful bursts, rather than delivering it through a smooth and continuous rotation. Applying torque this way has several benefits - 

1. Less kickback is produced from the tool, reducing strain on the operator's hands and wrists.
2. Prevents stalling when the tool is under heavy load.
3. Gradually breaks any resistance a fastener has by 'shocking' it loose.

No. Standard sockets, which are usually made from chrome vanadium, should never be used with an impact wrench because they are not designed to handle the shock and vibration generated by the power tool and may crack or shatter.

The operator should always use impact-rated sockets with an impact wrench.