When Not to Use an Impact Wrench?

Sometimes, impact wrenches can be a blessing. Other times, it’s better to leave them in your toolbox.

In this article, I will tell you when you should avoid using the impact wrench.

Impact Wrench is Extremely Powerful

As you know, impact wrenches are designed for high-torque, high-speed applications. Whether electrical or pneumatic, the tool has a hammer mechanism inside that delivers hammer blows to the bolts or nut heads hundreds of times per minute.
They are great for assembling and disassembling jobs at high speeds, and they can apply a lot of force as you just focus on holding it in place and squeezing the trigger.

But, with great power comes the great responsibility of using this tool in the right way.

10 Situations Where an Impact Wrench Should Not Be Used

Following is the list of specific cases where you should not use this powerful tool.

1. On Stripped Bolts or Nuts

Stripped bolts and nuts are probably over-stressed and weakened. Using an impact wrench on them can cause further damage to stripped threads, and it can also snap the fastener, making it even harder to remove.

2. Damage to Surrounding Materials

Don’t use an impact wrench on plastic parts, sheet metal, or painted surfaces. The tool’s high torque can damage the material or its surroundings.

Besides, the vibration produced by the hammering action of the tool can damage painted parts and dent, tear, or bend sheet metal.

3. When Accurate Torque Is Needed

Impact wrenches don’t have accurate torque settings. When you are adjusting parts that need you to apply a specified torque, using an impact wrench won’t help you to do it.

More importantly, using an impact wrench for tightening fasteners may over-torque the fastener, potentially damaging the fastener.

The impact wrench is not for tightening but for loosening the fastener. You can use it to spin the lug nut back on the bolt quickly. But always use a calibrated torque wrench when you want to tighten a fastener accurately.

4. Inadequate Space to Maneuver the Tool

When working in tight spaces, impact wrenches are usually a better option than a lot wrench. However, in some cases, impact wrenches can be hard to reach and maneuver. Their high torque output makes it difficult to keep them steady, and if the tool’s tip gets out from the socket, the tool can damage surrounding parts. Besides, the high torque and vibration of the tool can also damage sensitive and delicate nearby components.

If you can’t avoid using it in tight spaces, hold it firmly in place and apply short bursts to keep vibration to a minimum. A better option would be use a power ratchet.

5. Working with Delicate or Precise Parts

Using an impact tool near delicate or precise parts can already harm them.  Now, imagine using the impact gun on smaller-size fasteners or fasteners that are attached to sheet metal parts. The screw will strip before you even think of stopping the tool. That’s why you shouldn’t use these tools to work with delicate or precision parts.

Also, vibration can cause severe damage to plastic parts and render them unusable.

6. Where Noise is a Problem

Impact wrenches are loud, so you shouldn’t use them if the place doesn’t have enough acoustic insulation, and it could be a nuisance to other people or animals.

This also means it is probably not a good idea to use it in your apartment.

7. When You Don’t Have the Correct Size Socket

While this is true even in the case of hand tools, if the hand wrench slips, you are less likely to cause irreparable damage to the nut or bolt head. But with the high speed rotation, an impact wrench with an oversized socket can completely round off the fastener head in a single burst.

If this happens, it is a pain to remove the nut or bolt. Trust me, I know how bad it can be.

I have personally experienced this. I was on a weekend trip when my car tire got seriously damaged by a sharp metal piece pierced into this. I replaced it with the spare tire (I wish I had a bottle jack) and went to the local auto repair shop to get a new tire since I had to drive a long way. The apprentice mechanic took a wrong-sized socket and, before I could stop him, damaged the lug nuts!

8. Lack of Proper Safety Equipment

Always use ear protection and shock-absorbing hand gloves if you are using your impact wrench for an extended period. Don’t use it if you don’t have safety gear available. Even when you use it for short periods every day, you could suffer severe and/or irreversible injuries in a split second.

9. When You Do Not Have Impact Sockets

Never use regular chrome sockets in an impact wrench. They can crack or shatter, throwing pieces everywhere, which are like flying daggers. Regular sockets are not made to withstand the impact force and vibration of these tools.

Always use impact-rated sockets.

10. Using the Wrong Size Impact Wrench for The Task

Using a large impact wrench for a low-torque job can put too much torque over the fastener, damaging it. On the other hand, using a small tool for a demanding job can break the tool. Always ensure to use the right tool for the job.

For example, ¾ and ½ inch impact wrenches are ideal for automotive work, and 1″ or more is suitable for heavy-duty or industrial work.
Read this guide to find out the right impact wrench size for your job.

Tips for Identifying When Not to Use An Impact Wrench

• Check the screw hole’s thread for damage, rust, and other problems that may prevent the fastener from spinning properly. Also, check for damage on the bolts or nuts’ thread.
• Evaluate the working area. Check if you have enough room to maneuver and stay away from other parts that can be damaged by the tool. Besides, check if there is enough room to place the wrench at the correct angle (perpendicular to the fastener) to minimize the risk of damaging the fastener and the surface and get a proper sitting.
• Make sure to have the right-sized impact sockets for the job.
• Evaluate whether an impact wrench is the most appropriate tool for the job and if your tool has the right power and size to do it. If you are unsure, consider other alternatives before starting.
• Are you applying the final turns to adjust a nut or bolt? Then it’s time to leave your impact wrench aside and use another tool to make the final adjustment.

Alternatives to Using an Impact Wrench

Hand Tools: Traditional hand tools such as ratchets and socket wrenches can come in handy when you don’t want to take risks. For example, when you need to control torque or vibration can be a problem.

Breaker Bar for Extra Oomph: If you need more torque, consider using a proper breaker bar instead of an impact wrench. For example, a regular-sized ratchet won’t be enough to unfasten wheel lug nuts, but a reasonably long breaker bar will help you to safely do the job without over-torquing them.

Torque Wrench: When you need to apply precise torque to a fastener, you can use a torque wrench or a torque limiting extension bar if you want to control the torque output, but you don’t need as much precision.

Driving Screws: Use an electric screwdriver, a cordless drill driver, or an impact driver to drive the screws without stripping the head.

Impact Wrench Safety Tips

Before using an impact wrench, read the user’s manual carefully and follow the instruction.

Here are some of the safety precautions that you should follow:

• Wear Ear Protection: Impact wrenches are loud; always wear ear protection. If you work with other people, make sure everyone near also uses ear protection.
• Safety Glasses: Wear eye protection like safety goggles or a safety mask when using the tool.
• Use Anti-vibration Gloves: Impact tools transfer a lot of vibration onto your hand and can cause serious damage if you use the tool for an extended period of time.
• Prepare your tools and keep the working zone cleared, clean, and tidy. Keep children and pets away from your working area.
• Never use your impact wrench when you are exhausted. You can’t afford to be distracted as you work with power tools.
• Keep a safe distance between you and the object you are working on. The distance varies depending on the tool’s size and power output, but keep at least a clearance of about 30cm or 12”.
• Use a torque-limiting extension bar when needed. These bars break at a specified torque, acting like a fuse between the impact wrench and the fastener.

Conclusion

Impact wrenches are great and useful tools, but sometimes it’s vital to know when not to use them.

It’s important to remember that fasteners can break and be damaged, as impact wrenches can exert too much power over them; that’s why you should never use them to fully fasten bolts and nuts. Besides, always remember that power tools like these can be extremely dangerous; that’s why you must always take all the precautions to make your working experience safe and pleasant.

Last but not least, remember that traditional hand tools can complement your impact wrench and help you to do a great job.