You need to weld your exhaust pipe and want to save money by doing it yourself. Most exhaust systems are made from mild steel, stainless steel, or aluminized steel (rare).
Last year, I walked out to my car after work and noticed that it was extremely loud when I started it. Crawling underneath the car confirmed my suspicions: the catalytic converter bandits had stolen part of my exhaust pipe.
The cheapest way to fix an exhaust pipe is with a welder. Without a welder, you are going to have to unbolt the system and then bolt in a new system. Sometimes, with manifolds, you simply have to do that. But, in my scenario, I needed to weld in a new catalytic converter without replacing the entire system.
Gas Metal Arc Welding (GMAW) or MIG welding is the easiest process to use for exhaust welding. Exhaust pipes are notoriously thin and are prone to burning through with stick welding or even flux core welding.
Theoretically, you could weld exhaust back together by tack welding little “stitches” of weld beads. For example, you could tack it in 4 to 6 spots and then keep working your way around it in a circle, each time filling in the gaps a little more.
This would be a long process.
Mig welders with a low amperage setting and a high wire speed will require more skill but will let you get the weld done quickly without burning holes in the metal.
Best Welders For Exhaust Systems
Hobart 500559 Handler 140 – High End 110v Welder
The Hobart Handler 140 is one of the best welders to consider as an all-around shop tool. Whether you are welding exhaust systems or trying to build a garden cart out of angle iron, this little tool can handle it.
For beginners, it is extremely easy to use. Simply select your wire speed and amperage. A handy chart inside the door of the welder helps you easily get those dialed to the type of work you are doing. There is also a voltage setting that lets you customize the arc pattern and get a deeper and more consistent fusion of material.
Where this tool excels is in the smoothness of welding. The metal drive wheel on the automatic wire feed provides consistent, smooth delivery of welding wire. This allows even the novice to get that “bacon sizzle” on the first try. The weld beads that you get out of this are much smoother than you would expect for a tool at this price point. It is such a reliable welder than many auto shops use it as their sole welding tool.
The duty rating on this unit is on par with the others in its class. With 20% at 90 amps, you ‘ll need to take frequent breaks to make sure the tool doesn’t overheat. However, most of the users are doing smaller projects, so it doesn’t seem to be much of a hindrance.
This welder is heavier than some of the cheaper models, and you will likely want a cart to wheel it around on if you plan on using it quite a bit. With a five year limited warranty, this is one of those key pieces that you are going to be relying on for years to come.
YESWELDER TIG-205DS – Best Welder For Stainless Steel Pipes
Those of you working on stainless steel exhaust pipes, a DC-current TIG welder can be an excellent choice.
Tig welders are similar to MIG in that they need a supply of shielding gas connected to the welder. However, instead of automatic wire feeding, TIG systems use a rod that you have to “melt” into the seam with a hot arc. This creates a very distinctive (And beautiful) “stacked dimes” pattern.
With stainless steel, a TIG weld is strong and provides a rather pretty discoloration. You also can work gently without worrying about burning through the metal as TIG is much better at thinner metals, and is the preferred tool for welding sheet metal.
This one from YESWELDER is an excellent TIG Welding machine. It comes with IGBT soft switch technology for ultimate arc stability and control, providing a reliable, consistent weld bead. It also has automatic compensation for voltage fluctuations, which means there is less customization that you have to do.
The high frequency starts up makes this one easier for newbies to master as you only have to get the tip near the material, and it will automatically strike the arc and start the welding process.
There is a little bigger learning curve with TIG than with MIG, and most do-it-yourselfers choose to go with a high-end MIG system. However, if you are working on tuner cars or other performance models and one that showroom floor weld beads, this is a better option than the “get it done” MIG welders.
You will want to purchase a gas regulator to connect your argon bottle to this machine.
SungoldPower 200Amp 110v/220v Dual Voltage Welder
Are you feeling a little constrained by the power that these other welders offer? Here is an option that is designed to help you get the job done quickly, while also being able to handle the other jobs that come your way. As a dual voltage machine, it can work of both the standard 110v household current and the higher-powered 220v current systems. Not everyone has a shop with 220v circuits, but for working on metal thicker than 1/4″, you are going to need the added power.
The SungoldPower offers an affordable way to weld your muffler as well as just about anything else in the garage that has been broken for a while.
There are a lot of similar welders in this category. None of these are designed for production-level use, but the SungoldPower is more robust than the competition. For example, it uses a full-bridge IGBT inverter (compared to many of the others that use the weaker, half-bridge inverter. It also has an all-metal wire feed to deliver a more consistent wire-rate (similar to the Hobart above).
Because of the better build quality, it ends up weighing about 12 pounds more than the closest competitor.
It ships to your setup for flux core welding. If you are doing exhaust work, you will want to buy a regulator kit to go with it so that you can connect your gas tank.
This also ships with a stick welder attachment. Stick welding is handy to have any time you are working with rusty metal or need to do a unique job such as repairing cast iron or brazing two dissimilar metals together. Most farms have an arc welder around for handling those dirty jobs, and this one fits the bill with its 2-in-one system.
This is also the first welder on this list that is compatible with a spool gun. Spool guns are handy for welding aluminum as it holds the special wire on the handle to deliver a consistent feed. If you want to weld aluminum in the future, you will want to purchase the spool gun separately.
Overall, this is one of the best welders for the money. For the enthusiast who doesn’t like being limited by their tools, this is a good way to go.
Lincoln Electric Weld Pak 140 HD – Budget Welder for Beginners
The Lincoln Electric Weld Pak 140 offers brand name welding power at a price point that is attractive for the average homeowner to afford.
This kit comes ready to use out of the box. It includes the gas regulator and hoses as well as the Mig gun for doing your work.
The thing to keep in mind is that this is a 110-volt welder that is excellent for doing work on thinner metals, under 1/4 of an inch. It needs a 30 amp power circuit to access the full 140 amps of welding power. If you are working on a 20 amp system, it will only deliver about 90 amps.
This one also has a 20% duty cycle at 90 amps. This means that in a 10-minute window, you can weld for 2 minutes and need to let the machine rest for about 8 minutes to prevent overheating.
You can run either flux core welding wire through this welder or stick with the gas. For exhaust pipework, I will always recommend using a shielding gas instead of flux core wire. The ability to run flux core wire is handy for those situations where you don’t have gas available to finish a job.
This little welder is compact and great for carrying from job to job. You can save some money with it, and use it to weld an exhaust pipe. However, it is going to struggle with thicker metals.
Amico 160 Amp Digital Display Arc Welder
An Arc Welder Would not be my first choice of welding process for welding a muffler as they are going to be pretty hot and can burn right through the material that you are working with. Additionally, the sticks are a little hard to control, and you wouldn’t want to use them on the car unless you had a lot of room to work.
The advantage of an Arc welder is that it is an extremely affordable option. These little welders use a small stick for doing the welding that looks a little bit like a sparkler. You just scratch it on the metal to initiate the arc and then hold it a tiny bit away from the material as the bead forms. The trick is getting the stick close enough to the material that it arcs nut not so close that it sticks.
It takes a little bit of practice to master this technique.
However, if you want a budget-friendly welder that will run on any 110-volt circuit, this one will fit those criteria perfectly.
The digital readout makes it easy to dial it into your specifications, and it is an extremely lightweight welder making it easy to carry from job to job. You’ll also appreciate how quiet it is during operation.
Not everyone can afford a MIG welder, so having an affordable and reliable Arc welder on this list helps fill in the gap for those of you trying to repair your muffler on a bare-bones budget.
How To Weld Exhaust Pipe
Protect The Vehicle’s Electronics
Welding a pipe on the vehicle means introducing high amperage voltage to the body of the car. This creates a risk for frying computer systems. Even if you unplug the battery, the voltage can travel through the body of the car, through the ground wires, and into sensitive electronic components.
At the least, you want to clamp the welding clamp as close as possible to the space where you are working. This will decrease the distance that the current has to travel to find the ground.
However, a better suggestion would be to unplug the battery and the car’s computer modules. Typically those are relatively easy to access, and removing their wiring harness prior to welding can protect them against thousands of dollar’s worth of damage.
Clean The Welding Surface
You need a clean surface to weld on. Using a wire brush or an angle grinder with a brush, you want to sand the surface and expose shining metal so you can get a good welding bond.
It is possible that the area you are fixing is too far gone to properly clean. If so, you can cut the exhaust pipe back until you find solid metal and then replace the corroded portion.
Once your pipe is cut, bent (if needed), cleaned, and lined up, you can clamp it in place using tack clamps. A pipe clamp makes the job much easier for holding the butt ends of the muffler in place while you make little tack welds.
Once the muffler is tacked together, you can come back through and complete the welds to create an air-tight junction that won’t allow exhaust links.