Klutch MIG 140si MIG Welder Review

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In Brief: Klutch MIG 140si Welder Review

With dual flux core/MIG welding capabilities and lightweight design, the Klutch MIG 140si welder offers beginner-friendly welding with advanced results. This machine includes infinite voltage control and wire speed control and comes ready to use with an optional spool gun attachment for aluminum.

The Northern Tool & Equipment company manufactures the Klutch line of welders and welding products. This company focuses on providing equipment that lasts and convenient designs that work for home hobbyists.

The Klutch MIG 140si provides dual-process welding including both flux core and MIG options.

This machine keeps welding portable and accessible for beginners while allowing experienced users to hone their skills and perfect their precision welds.

Key Specifications of the Klutch MIG 140si

Klutch MIG 140SI Inverter-Powered Wire-Feed MIG Welder - 140 Amp Output

The Klutch MIG 140si welder comes ready for use out of the box. It includes the basics to help you get started MIG welding and provides the option for flux core welding as well.

With its infinite controls and simple design, this lightweight machine makes welding easy.

Check out the Klutch MIG 140si in action here –


Read the long list of Klutch MIG 140si specs below:

MIG, Flux Core
Power Supply
120V, 20A, 60Hz, 1-PH
No-Load Voltage
69V DC
Minimum Output
30A DC
Maximum Output
140A DC
Duty Cycle
30% @ 90A
19.7 in. x 8.7 in. x 15 in.
WarrantyCheck Manual
FeaturesSpool gun ready
Infinite voltage control
Wire speed control
AccessoriesGround cable and clamp
MIG gun and cable
Gas hose, regulator and flow gauge

Unique Features

With a spool gun ready design and easy controls with advanced options, the Klutch MIG 140si welder offers something for everyone.

Spool Gun Ready

This welder works with an optional spool gun attachment. Since it comes ready to accept a spool gun, you only need to plug in the gun, flip a switch, and use it right away.

Infinite Voltage Control

With infinite voltage control, experienced users enjoy the option to carefully change settings and find the precise adjustments needed to complete projects smoothly.

Wire Speed Control

The machine’s wire speed control function allows users to dial in the right wire speed and make adjustments quickly while working on projects.

Thermal Overload Protection

This welding machine features built-in thermal overload protection to prevent it from becoming damaged or unsafe due to overheating.

When the machine reaches a certain temperature, it shuts off until it cools down enough to operate safely again.

User-Friendly Interface

The Klutch MIG 140si welder comes standard with a user-friendly interface designed for beginners.

The simple dial controls provide convenient welding without much prior experience but allow advanced users to get creative with their welds, too.


Performance & Ease of Transportation

Portable design and powerful performance combine to make the Klutch MIG 140si a strong competitor in the world of lightweight dual-process MIG welders.


This welding machine handles mild steel and stainless steel easily out of the box. With the optional spool gun attachment, it tackles aluminum projects as well.

Customers enjoy working with this machine for both flux core and MIG welding.

Flux core welding operates slightly more smoothly on this machine than MIG welding, but both offer good results.

However, the included gas hose and regulator breaks easily, and customers often need to upgrade or replace it very quickly.

The wire feed on this welder holds up nicely to long-term use. Additionally, the switches function well and the dials turn easily for infinite controls.

Ease of Transportation

The Klutch MIG 140si welder weighs just 27 pounds. This lightweight style keeps it on the low end of the portable dual-process welder scale.

It also features a small profile that keeps it easy to pick up, move, and transport from place to place.

With a built-in handle and a 120V power supply, this machine travels around the home with no trouble. It plugs into household outlets and provides enough durability to remain stable and secure even when moved frequently.


Weld Quality and Available Options

Despite its petite design, the Klutch MIG 140si provides solid welds that last. Both MIG and flux core options create good results when used on steel, and the machine welds hot with smooth, clean results.

When used with gas, this welder tends to burn gas faster than some of its competitors. Despite this, the weld quality remains high.

The Klutch MIG 140si welder comes in just one option. Add the following to enhance your welding experience:

  • Quick Draw Spool Gun: This spool gun attaches easily to the machine and makes aluminum welding a possibility.
  • Gas upgrades: Because of the lower quality of the included gas hose and regulator, customers usually upgrade to a different gas setup quickly when purchasing this welder.

Ease of Maintenance, Repairs & Warranty

The Northern Tool & Equipment company provides some replacement parts available for purchase through the company web site. Customer service may offer other replacement parts as needed depending on the situation.

The company recommends customers refrain from repairing internal components on this machine. Only a licensed technician should access the interior of this welder.

Routine maintenance helps keep this machine up and running for longer. To perform this maintenance, begin by unplugging the power for at least 30 minutes and then removing the cover to access the inside.

Customers should not repair or replace any internal parts. However, customers should use compressed air to gently clean debris and dust from the interior of the machine.

Repeat this compressed air cleaning on the machine’s vents.

Regularly check cables, connectors, terminals, and consumables. Tighten any loose items and repair or replace any damaged ones. Do not operate this machine with damaged accessories or worn consumables installed.

The Northern Tool & Electric company provides a limited warranty for this welder.

The warranty covers three years of parts and labor on rectifiers, transformers, valves, switches, controls, drive motors, drive systems, and PC boards.

The warranty covers one year of parts and labor for MIG guns and cables. However, the warranty excludes consumables as well as expendable parts of the MIG gun.

Contact the Northern Tool & Electric company for more warranty information at 877-304-0294.


What type of wire feed roller does the Klutch MIG 140si come with?

This welder includes a knurled drive roller to make it possible to weld with flux core wire.

What type of gas works best with the Klutch MIG 140si welder?

This machine takes many types of gas with no trouble. For mild steel, customers often go with pure CO2. For aluminum, pure argon is best. An argon/CO2 gas mixture works well for all other types of metal.

Do you have to use gas when operating the Klutch MIG 140si welder?

It depends on the welding style you choose to use. For flux core welding, the machine runs without gas. For solid wire MIG welding, however, the machine requires shielding gas.

Does the tip of the MIG gun stay hot all the time on the Klutch MIG 140si welder?

No. The tip only heats up when you squeeze the trigger on the MIG gun. This provides safer, cleaner welding with less spatter.

Price of the Klutch MIG 140si

When compared with other dual-process MIG/flux core welders in the portable welding category, the Klutch MIG 140si welder comes in at a slightly lower price than its competitors.

This machine comes from a lesser-known product line than some of the big-name brands on the market. This helps keep the price lower without sacrificing anything in terms of quality.

The machine’s convenient settings and design, as well as its included peripherals, raise its value. Overall, the product remains worth the entry-level price for the majority of customers.


Who Should Buy the Klutch MIG 140si?

The Klutch MIG 140si welder makes welding easy and convenient for beginners.

Its simple dial controls and easy-to-use attachments ensure even the most inexperienced users complete MIG and flux core welding successfully.

Advanced users enjoy the ability to dial in precision controls and settings on this machine.

The portable design keeps it convenient for use in most household settings, and the included MIG gun makes setup a breeze for any user.

Our Recommendation

The Klutch MIG 140si welding machine packs plenty of functionality into a surprisingly tiny package.

It offers reliable MIG and flux core welding with a simple user interface and enough power to keep customers completing light to moderate welding projects for a long time to come.

We recommend this welder for beginners in need of a small welder to complete household repair and DIY projects.

We also recommend it for metal artists, auto repair hobbyists, and anyone else looking for simple, portable welding on a residential current.


Last update on 2024-05-30 / Affiliate links / Images from Amazon Product Advertising API

About Sharon Martin

Sharon loves to work on power tools and provides handyman services. She is an expert with both wood and metalwork. When free, she loves to hear country music and spend time with her cats.

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