Essential Info on How to Weld Cast Iron with MIG


Cast iron
stands as a very old and equally durable metal on the planet. Most of the cast
iron fittings we see around today have spent several decades with little
maintenance required.

But what if
a leak or tear pops up and you’ve only got a gas-aided welder? how to weld cast iron with
is where your focus will undoubtedly be.

A lot of
old projects relied on cast iron fittings based on its durability and
cost-effective build. These fittings have endured wear-and-tear over time. And
due to some circumstance, you’d need to get cast iron welded with MIG pretty

Here’re all
the facts you need and more to make the most from welding cast iron with a
shielding gas technique.

Is It Difficult To Weld
Cast Iron?

There’re several processes that support welding cast iron, and a few that could be tricky. Among the tricky methods for welding cast iron is MIG and TIG welding.

It’s not an
indication that these methods won’t work in getting a weld put together. On the
flip side, weld durability and cohesiveness get compromised cheaply with these

The Best Way to MIG Weld
Cast Iron

  • When you’ve got both surfaces of the cast iron clean and grinded, set it aside to cool.
  • Oiled parts have to get pre-heated to remove any obstructions to a smooth weld.
  • Grind off broken and rusted parts, creating a flush join between two cast iron pieces
  • Tack at each end of the weld for flat plates, and at rounded plates create tack beads at four cardinal spots
  • Use a high argon shielding gas and nickel filler wire.
  • Make use of the pull technique, dragging the weld in short bursts across the plate. Ensure your weld beads remain within a half inch for every drag.
  • Allow each section to cool before beginning another join to avoid disintegration
  • After the previous section cools, continue with the next section until the entire base metal is fully welded.

What Kind of Filler Wire
is best for MIG Welding Cast Iron?

Nickel wire
remains an excellent choice for MIG welding cast iron. But there’s a heavy
price tag attached to purchasing nickel wire.

To make the most from welding cast iron using the MIG process, it’s better to opt for steel filler wire instead. Steel wire is readily available and doesn’t cost much less than a nickel.

What Gas Mixture Do You
Need to MIG Weld Cast Iron?

The kind of gas you select depends on the cast iron you’re looking to weld. Much older cast iron that requires welding will work better with a high carbon shielding gas (50% CA and 50% other gases).

But if a
decent high carbon gas mixture is hard to find, you’d have to use a high argon
shield. (±80% argon and ±20 other gases with a major carbon percentage)

Final Word

If you’ve
been lost on how to weld cast iron with
, this read has surely provided everything you need to know. Get the
best info that’ll make you MIG weld cast iron like a pro to work. It’s certain
you’d get exceptional results when you’re through.