MIG or Flux Core?

Which welder do you need? Flux core or MIG? Granted, for small budget operations, Flux Core does make an appealing case. There’s less equipment to buy to keep up with and a lower initial purchase cost for a flux core only welder. That’s really appealing to most customers. Flux core welders of this caliber are usually 120V as well. A small, relatively cheap roll of flux wire is not expensive either compared to the cost of getting started with MIG, that likely requires a cylinder purchase/lease, gas purchase, regulator purchase, and 240V rewiring of your house. There are also many low cost options for flux core welders on the market. Flux core is also a great choice for outside environments where carrying an argon cylinder may be cumbersome, and where the wind may blow the shielding gas off the weld. So what’s the drawback? There’s a lot of spatter. It’s not as clean. And, the welds must be cleaned between passes. The welds aren’t as smooth. When it comes to weld appearance, especially with a small non-commercial flux core welder, the welds aren’t as good as MIG. Additionally the cost of flux core wire does add up. It’s considerably more expensive than the solid mig wire and when added up over time, it outweighs the cost of MIG wire and the shielding gas combined for the same amount of wire consumed. Typically you’ll find that a only a small amount of people really prefer flux-core over mig, in the DIY market. Commercially there are many valid applications for Flux-Core welding, especially in outdoor environments. It’s commonly used on bridge work, pipe or any field that requires large heavy amounts of high production work in an open environment.

As far as MIG goes, there are many advantages. The welds are cleaner, smoother, and quieter. Cleanup time can be cut down to almost nothing, compared to flux core. In an indoor setting it is hard to beat MIG for production welding. It’s fast and economical. Training requirements are low. Welding stainless and aluminum is usually not a problem, especially if it has a spool gun capability, which is unheard of on a most Flux Core rigs. Many smaller MIGs are now either made in single voltage 120V or dual voltage 120/240 to accommodate a variety of power sources. But operating on 120V, it will require more power to make the same weld than Flux Core because of it’s shallower penetration. Welds made with MIG can be just as structurally sound as any other process, provided there’s good shielding from the wind and the proper flow rate of shielding gas is used. The disadvantages are that leasing a cylinder cost more than most people with a home shop will return from the welder every year. The 70-100.00 lease bill floating in every year can be annoying. Outdoors, MIG does suffer quite a bit from drafts. It’s not something that can’t be over come however. Proper shielding can be set up to knock down the breezes.

Most people are initially drawn by the flux core’s capability outdoors and low price point. Keep in mind though that most MIG welders will also weld flux core, with only a small additional investment. With a MIG it doesn’t have to be dedicated to MIG only, it can double for both when it’s necessary. Unfortunately for small Flux core machines, you’re stuck with it, if you have it.