• Post author:
  • Post last modified:February 14, 2024

Changing the MIG (Metal Inert Gas) gun liner is a routine maintenance task that ensures optimal performance of your welding machine. The liner is a crucial component of a mig welder. It guides the welding wire from the wire spool to the contact tip at the end of the MIG gun. 

Over time, the liner can become worn or clogged with debris, affecting the smooth and consistent feeding of the welding wire. Or because of changing mig guns, you may need to change the mig liner. Because you can’t use uniform liner in all guns. 

In this guide, I will cover the step-by-step process of changing the MIG gun liner.

Preparing for Liner Replacement

Before you start to replace the MIG gun liner, it is important to prepare yourself and your work area. This will ensure that the process goes smoothly and safely.

In this section, we will cover the safety precautions you need to take, the tools and materials you will need, and the initial steps you should take before starting the liner replacement.

Safety Precautions

Safety should always be your top priority when working with any welding equipment. Here are some safety precautions you should take before replacing your MIG liner:

  • Make sure the power source is turned off and unplug the welder.
  • Allow the gun to cool down before you start replacing the liner.
  • Wear protective gear such as gloves to protect your hands.
  • Make sure your work area is well-ventilated to avoid inhaling fumes.
  • Keep flammable materials away from your work area.

Tools and Materials Needed

Before you start replacing the MIG gun liner, make sure you have the following tools and materials:

  • New MIG gun liner
  • Wrench
  • Pliers
  • Wire cutters
  • Cleaning brush
  • Lubricant

Initial Steps

Once you have taken the necessary safety precautions and gathered the required tools and materials, you can start the replacement work.

Follow these initial steps:

  1. Remove the MIG gun from the welder and disconnect it from the wire feeder.
  2. Cool down the welder and mig gun if you need to change the liner at the midst of any project
  3. Remove the contact tip and the gas diffuser from the MIG gun.
  4. Pull out the old liner from the MIG gun. You need to pull it from the end of the place where the tip is presented. 
  5. If there is debris or dirt inside the gun, clean them with the help of a brush or clean clothes. You can use a blower machine to do the job also. 
  6. Lubricate the new liner with lubricant. It will make it easier to insert into the MIG gun.

Following these initial steps will ensure that you are ready to replace the MIG gun liner safely and efficiently.

Change the MIG Welder Liner

If you’re having wire feeding issues or experiencing inconsistent welds, it may be time to replace your MIG welder liner. The liner is a crucial component of the MIG gun, as it guides the welding wire from the drive roll to the contact tip.

Here’s how you can replace the liner on your MIG gun.

1. Removing the Old Liner

Before you begin, make sure your power supply is off and the gun is removed from the wire feeder. Start by removing the nozzle, contact tip, and gas diffuser with the help of a plier. If your power pin uses a welder liner set screw, loosen the set screw using a 5/64 inch Allen wrench.

Next, remove the old torch liner from the MIG gun. You can do this by pulling it out from the back of the gun. If it’s stuck, you may need to use pliers to help remove it.

2. Installing the New Liner

Once you’ve removed the old liner, it’s time to install the new one. Begin by straightening out the cable and laying it in a clean area. Take your new liner and insert it into the back of the gun. Make sure it’s pushed in all the way.

Next, feed the liner through the gun until it comes out the other end. Use a wire liner gauge or ruler to ensure the liner is the correct length. Once you’ve confirmed the length, trim the liner to size using a liner cutter.

3. Final Adjustments

With the new liner installed, it’s time to make some final adjustments. First, reattach the gas diffuser, contact tip, and nozzle. If your power pin uses a liner set screw, tighten the set screw.

Next, turn on your power supply and test the wire feed. If everything is working properly, you’re good to go. If you’re still experiencing issues, double-check your liner installation and make sure everything is properly aligned.

Replacing your MIG gun liner is a simple process that can greatly improve your welding performance. By following these steps, you can ensure that your MIG gun is operating at its best.

Post-Replacement Checks and Maintenance

After replacing your MIG gun liner, there are a few post-replacement checks and ongoing maintenance tips that you should follow to ensure that your welding remains safe and efficient.

Testing the Gun

Before using the gun, it’s important to test it to ensure that everything is working correctly. First, check the wire feed to ensure that it is running smoothly. Then, check the gas flow to make sure that it is consistent and not fluctuating. Finally, test the weld quality to ensure that the gun is producing clean, strong welds.

Ongoing Maintenance Tips

Regular maintenance is key to ensuring that your MIG gun liner continues to function correctly. Here are a few tips to keep in mind:

  • Clean the gun regularly: Dirt and debris can build up in your gun over time, so it’s important to clean it regularly. Use a wire brush to remove any debris from the liner and nozzle, and wipe down the gun with a clean cloth.
  • Check the liner regularly: Over time, the liner can become worn or damaged, which can affect the quality of your welds. Check the liner regularly and replace it if you notice any signs of wear or damage.
  • Check the contact tip regularly: The contact tip is another important component of your MIG gun, and it can become damaged or clogged over time. Check the contact tip regularly and replace it if you notice any signs of wear or damage.
  • Use the right wire: Different types of welding wire require different types of liners. Make sure that you are using the right type of liner for the wire that you are using.

By following these post-replacement checks and ongoing maintenance tips, you can ensure that your MIG gun liner continues to function correctly and that your welding remains safe and efficient.

Watch the video on how to install liner in your mig gun

Frequently Asked Questions

1. How do you determine the correct size of a MIG gun liner for aluminum welding?

To determine the correct size of a MIG gun liner for aluminum welding, you need to consider the diameter of the aluminum wire you are using. The liner should have an inner diameter that is slightly larger than the diameter of the wire.
For example, if you are using 0.035-inch aluminum spool wire, you should use a torch liner with an inner diameter of above 0.035″ say 0.040 inches.

2. What is the process for changing a Tweco MIG gun liner?

To change a Tweco MIG gun liner, you need to first remove the nozzle and contact tip from the gun. Then, remove the retaining nut and pull the old liner out of the gun.
Insert the new liner into the gun, making sure that it is fully seated. Reinstall the retaining nut, contact tip, and nozzle.

3. How can you tell when it’s time to replace the liner on your MIG welder?

You should replace the liner on your MIG welder if you notice any kinks or bends in the liner, if the liner is dirty or worn, or if you are experiencing feeding problems.
Additionally, if you are changing the type or size of wire you are using, you may need to change the liner to match.

4. Is it necessary to cut the MIG gun liner?

Yes, it is necessary to cut the MIG gun liner to the correct length for your gun. To do this, first, remove the old liner from the gun and measure it. Then, cut the new liner to the same length, making sure to leave a little extra length at the end to allow for trimming.
Finally, install the new liner into the gun.

5. What are the common mistakes to avoid when replacing a Lincoln MIG gun liner?

When replacing a Lincoln MIG gun liner, some common mistakes to avoid include not properly seating the liner, not cutting the liner to the correct length, and not tightening the retaining nut enough.
Additionally, if you are changing the type or size of wire you are using, be sure to match the liner to the wire.

Conclusion

You must check the liner everytime you face any problems. Regularly checking and replacing the liner helps reduce the premature wear of mig wire. Also this practice increases the lifespan of your mig gun to some extended period.

So replace the liner when it is necessary.

Related Article

Maidul Islam

I am Maidul Shakil and am a welder for more that 6 years. Welding metals and joining them is my hobby and passion. I have learnt all welding techniques, safety issues, fabrication process and rigging from SUNY Westchester Community College . I am now trying to teach beginners about welding to encourage them to come to the field.

Leave a Reply