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La-Co

La-Co Water Soluble Soldering Flux Paste 16 oz

SKU CH-0BME-SGD75

Water-soluble organic paste flux for lead-free and tin-lead soldering on copper, brass and steel; cleans with water and meets ASTM B813, MIL-F-4995 Type II and NSF 61 standards

  • TypeWater Soluble Paste
  • MaterialOrganic
  • Water-soluble formula simplifies post-solder cleanup with water
  • Organic paste composition suits potable water systems per NSF 61
  • Withstands temperatures up to 840 Degrees F for reliable joints
  • Meets ASTM B813 and MIL-F-4995 Type II industry standards
  • Compatible with copper, brass, steel, nickel, silver and zinc alloys

Soldering Flux Paste for Plumbing Joints

This water-soluble flux paste is formulated for joining copper to copper and copper to brass using lead-free or tin-lead solders. It meets ASTM B813 and NSF 61 standards, making it suitable for potable water systems. The organic material activates up to 840 degrees Fahrenheit. Plumbers and HVAC technicians will find it reliable for general piping work.

Jar Packaging and Broad Metal Compatibility

The 16 oz jar provides a wide opening for easy brush access during repetitive joint preparation. The paste adheres well to vertical pipe runs without excessive dripping. It is compatible with brass, copper, galvanized iron, lead, malleable iron, mild steel, nickel, silver, terne plate, tin, and zinc. This versatility reduces the need for multiple flux types on a job site.

Water Clean-Up and Residue Management

Residue washes away with water after soldering, eliminating the need for chemical cleaners and simplifying the final inspection. The flux meets MIL-F-4995 Type II specifications for corrosion resistance. Because it is water soluble, any remaining flux will not cause long-term pipe degradation if flushed properly. Normal use produces minimal fumes at typical soldering temperatures.

Highlights

  • Water-soluble formula simplifies post-solder cleanup with water
  • Organic paste composition suits potable water systems per NSF 61
  • Withstands temperatures up to 840 Degrees F for reliable joints
  • Meets ASTM B813 and MIL-F-4995 Type II industry standards
  • Compatible with copper, brass, steel, nickel, silver and zinc alloys

Specifications

BrandLA-CO
TypeWater Soluble Paste
MaterialOrganic

Questions about this item

What does the ASTM B813 standard mean for this flux?

ASTM B813 certifies the flux for potable-water piping, so joints meet NSF 61 drinking-water requirements after proper flushing.

What size opening does the 16 oz jar need for a brush?

The wide-mouth jar accepts standard 1-inch acid brushes and allows easy paste scooping without decanting.

Which step do installers often skip when using water-soluble flux?

Thorough hot-water flushing after soldering; residue left inside the pipe remains corrosive and violates NSF 61 compliance.

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