Pneumatic Impact Wrench - Size Matters

Every DIY enthusiast, mechanic or tradesman, no matter their level of experience, reaches a point when they need something with a little more power – something a little more heavy duty.

Pneumatic impact wrenches provide just such a boost. Providing superior torque and results, impact wrenches make tightening or loosening even the hardest nuts and bolts a synch.

However, within pneumatic air wrenches there are different models with different capabilities. In this article, we will look at the difference between 1/2 “and 1” pneumatic impact wrenches and their different capabilities.


When it comes to torque, pneumatic socket wrenches sit at the top of the power mountain. Electric impact wrenches – cordless or corded, simply cannot provide the same amount of torque.

Because an air tool comes into play when heavy work is underway, it is important to note than only the very top-tier (and, in turn, the most expensive) electric impact wrench can compete with a pneumatic version.

However, the cost of a top-class electric air hammer loses any viability when compared to even a modestly priced pneumatic model, making them a very niche choice.

  • Electric wrenches cannot give the same torque as a pneumatic model
  • Only the very best and most expensive electric socket wrenches can approach pneumatic power levels

Once we begin to look closely at pneumatic  wrenches, we can see just how much power they provide. At the same time, they only require compressed air to operate – that means no cords, battery packs or crazy power usage.

For example, a ½” pneumatic wrench can provide 775 foot pounds of torque, whilst a 1” CP7773 model Chicago pneumatic wrench offers 1200 foot pounds of torque, all from simple compressed air.

These power levels are more than enough for removing the rustiest nuts and taking on even the toughest of jobs.

In terms of torque-to-cost, there is no better option than a pneumatic socket wrench.

Weight and Portability

For most – no matter their trade, weight of tools makes a big difference. For those travelling from job to job, it can mean the difference between a backbreaking load and a compact, effective tool set.

For example, a cordless electric wrench, because of its great power usage, requires a number of power packs and perhaps outlet points. Whilst it offers a portable solution for a while, going electric requires tethering to electricity in some form or another.

Air hammers, on the other hand, requires compressed air and nothing more. This means quick, easy charging and a source of power than can travel anywhere – no matter how isolated the work location.

A ½” Chicago CP8252 pneumatic impact wrench weighs only 2kg, making it the perfect combination of power and portability. The right weight for any toolbox or workshop, its small weight and size – 7.9 inches in length, puts the most troublesome jobs within reach.

The more powerful 1” pneumatic wrench weighs in at a heftier 5.5kg, but still provides an amazing power-to-weight ratio that is far beyond the capabilities of any electric equivalent.

In terms of working on the move, a ½” pneumatic impact tool will probably win out, as it offers half the weight of its bigger brother and better portability.

However, both offer a great, powerful wrench that goes unhindered by a lack of electricity. If the job takes place in a field, ten miles from civilization, a pneumatic impact wrench will get it done.

  • A ½” pneumatic wrench weighs only 2kg, whilst the bigger 1” weighs in at 5.5kg
  • No need for electricity makes even the most remote jobs easy to get to
  • Smaller models are perfect for work on the move

Air Consumption

For some, the main concern with pneumatic impact tool is air consumption. The worry is that the wrench will use a massive amount of air to deliver torque.

The more powerful the wrench, the more compressed air it will use, as there is only so efficient a pneumatic wrench can be. However, many modern air wrenches deliver great air-consumption-to-power ratios.

A 1” CP7773 Chicago  wrench has a 3/8 inch air inlet thread size, and delivers 6300 RPM and 1200 foot pounds of torque. A decade ago or less, a air socket wrench could not have delivered such power and offered such low air consumption.

At the same time, a ½” wrench comes with a ¼” air inlet size and offers  maximum torque of 775 foot pounds and 9000 rpm, all whilst using just 3.4 litres of air per second.

When contrasted to the amount of electricity used by an electric cordless or corded impact wrench, air always comes out on top in power, convenience and portability.

  • Even from just a decade prior, air wrenches are much more efficient
  • No other type of impact wrench offers the same power, portability and efficiency as pneumatic