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Fine Line Weld & Build LLC

Heavy plate & deep penetration

Flux Core Welding (FCAW)

Flux core welding runs a tubular wire with flux inside it. Self-shielded, it makes its own protection like stick does, but it feeds continuously like MIG — so you get outdoor tolerance with production speed.

On thick plate and structural sections it lays down more metal per pass than anything else we run, with deep penetration into the joint.

What the job includes

  • Self-shielded FCAW for outdoor structural work
  • Heavy plate and thick section welding
  • High-deposition multi-pass welds
  • Out-of-position welding on erected steel
  • Wire and procedure matched to the section

Where it gets used

  • Structural steel erection and field connections
  • Heavy plate fabrication and repair
  • Outdoor work where MIG shielding would blow away
  • Thick joints where a single-pass weld will not carry the load

Common questions

How is flux core different from MIG?

Both feed wire continuously, but flux core carries its shielding inside the wire, so it works outdoors where MIG's gas would blow away. It also deposits more metal per pass on thick material.

Is flux core good for thin metal?

Not really. It runs hot and deposits fast, which burns straight through light gauge. For thin material we use MIG.

Does it leave slag?

Yes, and it has to be chipped and cleaned between passes. That is part of the job and it is included — we do not leave slag on a finished weld.

Tell us what needs welding.

Send drawings, photos or dimensions — or just describe it. We will tell you straight whether we are the right crew for it.