For any tightening or unscrewing task ahead of you, an impact wrench is a tool that would help you get the job done. However, it is the torque that would enable you to get the best out of this tool and deal with the problem effectively.
It is crucial that you get the correct torque since any deficit or excess may either leave you with unsatisfactory results or lasting damage to the material you are working on.
If you are a handyman who has a hard time knowing the ideal amount of torque to use for a particular application, you are not alone, as it is a common issue out there. Luckily for you, this piece aims to educate you on that subject further.
Have a read!
Table of Contents
What is Torque and Why Does It Matter for an Impact Wrench?
In general, we can define torque as the measure of the rotational force that causes an item to rotate. In our case, it is the force that causes the impact wrench’s drive to rotate. Alternatively, we could say that it is the tool’s twisting force that is needed to get the job done.
So, as the drive rotates, it either loosens or tightens nuts and bolts. With the impact wrench, it does not rely on the rotational force only to loosen or tighten bolts and nuts but has an additional hammer mechanism to make it more effective.
This hammer is vital in providing the extra force that reinforces the drive if it encounters any resistance.
How Much Torque Do I Need in an Impact Wrench?
It all depends on the type of task that you are handling. For instance, a large project such as rail construction may require a torque of up to 700ft-lbs. And for a smaller task such as removing lug nuts from car tires, you will need a torque of 350 ft-lbs.
So, the torque varies from one task to another and using too little, or much of it may not get you the results that you were looking for. Therefore, it is vital that you first know the force needed for the job so that you can set your impact wrench to that particular torque.
Adjusting the Torque in an Impact Wrench
As we mentioned before, there is no standard torque for every task that you will be dealing with. However, it would be costly to get a different tool for every task, and that is why we suggest that you learn how to adjust the torque to the level you are looking for.
For modern tools, making this adjustment is a straightforward affair since it involves setting a dial to achieve your target. But for the pneumatic wrenches, you may have limited options, and we shall look at two major ways of doing so:
I) Regulating the Line Pressure
This method involves regulating the amount of pressure that comes from the air compressor. To regulate the pressure, follow the simple steps below:
- Start by powering on your compressor and allow it to run until it attains maximum pressure
- Then, use an air nose to attach the air compressor to your impact wrench
- After that, reduce the pressure gradually by setting the regulator on your wrench until it attains the torque that you desire
II) Regulating the Tool Pressure
The other method is most suitable for you if your impact wrench does not come with an inbuilt air regulator. Here, you will be passing pressure from the compressor through an air regulator and finally to the impact wrench.
To regulate the tool pressure, the steps are as follows:
- Connect a tool air regulator to the impact wrench before connecting the air nose to the regulator
- Then, simply adjust the regulator until you achieve the desired torque
How to Increase Torque
Even though manufacturers advise against modifying torque settings beyond the recommended limits, you could still do so at your violation. So, instead of getting a more powerful impact wrench, you could follow the steps below and increase your tool’s torque beyond the set limit.
- Start by disassembling the impact wrench. Remove the rear plate and then extract the motor and cylinder
- Use a Dremel to create a new shape on the cylinder ports and do this process for both the front and back of the cylinder
- Then, open the exhaust ports on the cylinder to reveal the endplate and grind it so as to enlarge the inlet ports. Ensure that both ports are of equal size while you should leave a space large enough for the screw hole
- Cut the paper gasket to match the new ports that you have created
- Lastly, assemble the impact wrench back into one piece and remember to clean everything up
We hope our article has told you everything you needed to know about the required torque for an impact wrench. In this piece, we have also provided you with simple guidelines on how you could adjust the torque to your desired levels so that you can get the best results after operation. Always keep in mind that different tasks will need different measures of torque to get the perfect results.