How to Weld an Exhaust Pipe with Stick, Flux, TIG and MIG welding

Last Updated on May 2022


It is not uncommon for your car`s exhaust pipe to need slight repairs over time.

These mufflers are always on the use, and as a result, can wear out quite fast.

Luckily, with some basic welding knowledge, you won`t need to visit a car repair shop to have your exhaust pipe sorted.

This is where DIY welding comes in handy; you can save on that repair cash and weld your muffler at your home garage or workshop.

Of course, regardless of your experience level, it is prudent to understand the basics of welding an exhaust pipe.

Welding a muffler without the necessary techniques can make the situation worse, which does little to boost your morale as an expert DIY welder.

Luckily, in this read, we will share everything about welding exhaust pipes through the most popular welding techniques.

Read on to as we break down the exhaust pipe welding process using stick, flux, TIG and MIG welding.

The Four Main Steps Associated with Welding

To successfully weld an exhaust pipe, you must have several repair tools at hand. Of course, a functional welder is top on the list. You will also need a hacksaw, grinder, circular chain saw and welding mask.

Below are some of the main steps you will need to observe when welding your exhaust tube

Cut the Pipe

This process is not as straightforward as it might appear at first. You need to cut the muffler with great precision as your cutting technique will play an instrumental role in determining the final appearance of the exhaust pipe. The first step is to mark out the pipe and identify the cutting areas.

Proceed to use a hacksaw or chain pipe cutter to cut the exhaust tubing as neatly as possibly. Cutting straight will make the job more professional and attractive. After you are done, you can proceed to use a grinder to remove the imperfections on the edges and make it finer. Grinding also helps to expose the base metal as it removes dirt, rust or paint that could be on the surface. This allows you to get an impurity free, clean weld.

 Clamp the Pieces

After preparing the tubing pieces through thorough cleaning, the next step is to clamp the pieces. C-clamps will help you in this process. Their function will be to hold the tubing together (two-piece) before you begin to weld. Remember, it is crucial to fit the tubing in your preferred style as these adjustments need to be accounted for when using a c-clamp.

Spot Welding

Since exhaust tubing are usually thin, using spot welds is advisable (doing three to five tiny welds around the tube). Worry not, though, warping will be prevented as a result of the high heat produced when welding. It is easy to bend gaps into place in case they occur on the tube`s opposite side since spot welds play the important role of holding the tube in place.

Complete the Weld

Proceed to weld the gaps remaining in the tubing after spot welding. It is crucial to weld all-round the tubing`s circumference to eliminate the probability of leaks.  For a durable and sturdy weld, we recommend welding over the spot welds.

Using Stick Welding to Weld the Exhaust Pipe

While some might argue that stick welding is not ideal for exhaust pipe repair, you will be shocked to learn that you can successfully use a stick welder and achieve great results. However, be ready to think outside the box when going the stick welding way to repair your muffler.

The first and all-important step is understanding the ideal rod to use. We prefer the 6011 rod for its precise welds on soft surfaces. Also, be sure to go for the thinnest 6011 rod you can get your hands on. The 6011 rod will help you out when spot welding before welding around the muffler`s circumference.

Although stick welding is rarely affected by dirt, paint or rust, we nonetheless urge you to clean the surface to avoid slag.

Pros of using Stick Welding to Fix your Exhaust Pipe

  • You can stick weld anywhere whether outdoors or inside the workshop
  • Stick welding is possible in all weather conditions
  • Stick welding is not sensitive to paint, dirt and rust compared to other welding techniques
  • Stick welding equipment is fairly easy to use and inexpensive

Cons of Stick Welding

  • If not done well, stick welding can lead to the production of slag which can lead to leaks
  • You will use several electrodes

Tips on Staying Safe when Stick Welding your Exhaust

  • Always wear the required protective attire from gloves to welding masks to keep your skin and eyes protected.
  • It is best to maintain a low amperage range to prevent overheating your stick welder and burning through your muffler
  • Stick welding releases heavy fumes; be sure to weld in a properly-ventilated room
  • Never weld when the muffler is attached to the vehicle as the resulting sparks can lead to explosions

 Exhaust Pipe Welding using Flux Core Welding

While not a highly recommended way to repair your exhaust pipe, you can still use gasless flux-core welding to DIY fix your muffler. When flux core welding, however, it is advisable to clean the tubing to reduce the resulting spatter produced.

You should also be prepared to adjust your amperage settings while also reducing the amperage since flux-core welding can produce hotter arcs. The wire feed speed should also be adjusted to make shorter beads and avoid burning through the tube as a result of an extremely hot arc.

Pros of Welding your Exhaust Pipe using Flux-Core Welding

  • Can be done without the need of a gas shielding tank
  • Provides better penetration compared to MIG electrodes
  • Cost is less than that of using MIG wires
  • The cost of equipment is far less compared to MIG and TIG welding
  • The wire is continuously fed thus removing the need of changing the electrode continuously

Disadvantages of Welding the Exhaust using Flux-Core

  • Can easily burn through thin metals, thus needing a high level of precision
  • Flux-core welding will produce more spatter.

 Safety Tips for using Flux Core Weld

  • Wear welding goggles all the time when flux core welding to protect your eyes from heat and UV rays
  • Always were closed shoes to protect your toes and feet from sparks arising from flux core welding
  • Also wear long, fire resistant pants that will protect your feet from the risk of catching fire due to the sparks
  • Always glove up since flux core wires tend to become hot. The gloves should be long enough to provide forearm protection

Exhaust Pipe Welding Using MIG Welding

Compared to stick and flux-core welding, MIG welding is more suited for welding exhaust pipes. You can do a great job fixing your muffler and have it look as good as new. To start welding your exhaust pipes, the first task is to prepare your base metal by cleaning it thoroughly. Ensure that your tubing is completely free of rust and dust. A metal brush will be useful in cleaning the muffler`s tubing and consequently expose the base metal.

We recommend using a combination of carbon dioxide and argon to MIG weld your exhaust pipe. To avoid burning through your exhaust, it is ideal to use a medium amperage range to avoid burning the soft surface.

Advantages of MIG Welding Exhaust Pipe

  • You don’t have to worry about slag since there will be no flux when welding your exhaust
  • You can successfully MIG weld using full and semi-automatic techniques
  • You can use MIG welding on alloys due to its versatility
  • Faster and better welding technique that flux core and stick welding

Disadvantages of MIG Weld Exhaust

  • Requires an external shielding gas tank, thus making it fairly demanding
  • Cannot be used outside or on windy conditions

Safety tips to consider when MIG Welding your Exhaust

  • Always wear fireproof welding gloves since MIG welding creates a hot arc
  • Put on closed-toe shoes to protect your feet from sparks
  • Put on a welding mask to prevent the fumes and harmful UV rays from reaching your face

Welding your Exhaust using TIG Welding

TIG welding is ideal and built for welding thin metal sheets such as exhaust tubing. You can use this technique to weld exhaust pipes made from sensitive alloys like stainless steel. However, you must take extra precaution to TIG weld your exhaust pipe.

Your base surface should be completely free of oils, rust, paint and dirt. The first part is cleaning the tubing and ensuring that no residues are left. Having an acetone raced lag by your side will help to remove oils that might be left as residue emerging from the thick lube oils used on mufflers.

When TIG welding, the most ideal tungsten rod to utilize is a 3/32 inch rod while the filler rod should be the smallest you can get. Your head output needs to be precise due to the soft nature of exhaust tubing. Using a foot pedal can help you adjust the overall heat output depending on the thickness of your metal. Since TIG welding is ideal for thin metals and surfaces, we recommend using it to weld your exhaust pipe.

Advantages of Welding your Exhaust Pipe Using TIG

  • The most ideal welding technique for thin metal sheets like exhaust tubing is TIG welding
  • The resulting weld in usually clean, neat, free from slag and aesthetically appealing
  • TIG welding produces less heat when compared to other welding techniques, making it ideal for thin metals
  • TIG welding is ideal for welding a wide range of thin metal and alloys

Cons of Welding Exhaust Pipes using TIG

  • Takes time to set up by cleaning and compared to other techniques

Safety Tips for TIG Weld Exhaust

  • Always have a long-sleeved apron on that is made from material that is non-flammable to eliminate the risk of fire
  • Wear earplugs to keep your ears safe from sparks that result from welding
  • A face shield should come in handy in protecting your face and eyes from sparks as well as harmful fumes.


Exhaust pipes are usually made from soft metal. Some are even made from alloys, making them extra sensitive to heat. Therefore, to prevent the welds from running through the base metal, it is ideal to choose the right welding technique.

We recommend using TIG welding as it is ideal for use on smooth and highly sensitive metal surfaces and the best for exhaust tubing. You can also use MIG welding if you don’t have the necessary tools for TIG welding.

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