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Black soldering flux paste in a wide 80 oz jar

Harris

Harris Soldering Flux Paste 80 oz SSBF5

SKU CH-CWMZ-NJCTD

Soldering flux paste in an 80 oz jar works from 1,050 to 1,800 °F for high-silver and phos-copper alloys

  • TypeSoldering Flux
  • Soldering flux paste in an 80 oz container
  • Wide active temperature range from 1,050 to 1,800 Degrees F
  • AWS FB3-C classification for reliable brazing performance
  • Paste form ensures easy application and control
  • Suitable for high silver and phos copper alloys

Harris Soldering Flux Paste 80 oz

This Harris soldering flux paste comes in an 80 oz jar for brazing applications. It is formulated for high silver and phos copper alloys. The flux activates between 1,050 and 1,800 degrees Fahrenheit. It carries AWS FB3-C classification for professional use.

Suited for brazing high silver

This flux serves technicians joining copper or silver-bearing alloys within the stated temperature range. The paste form allows precise application on joints. Buyers needing flux for aluminium, stainless steel or soft soldering should look at other products. It is restricted from sale in California due to Proposition 65 chemical warnings.

Active temperature range 1,050 to 1,800 degrees

The flux becomes active at 1,050 degrees Fahrenheit and remains effective up to 1,800 degrees Fahrenheit. This window determines whether the paste matches your brazing process. Verify your alloy melting points fall inside this range before purchase.

Highlights

  • Soldering flux paste in an 80 oz container
  • Wide active temperature range from 1,050 to 1,800 Degrees F
  • AWS FB3-C classification for reliable brazing performance
  • Paste form ensures easy application and control
  • Suitable for high silver and phos copper alloys

Specifications

BrandHarris
TypeSoldering Flux

Questions about this item

How long will the flux stay active at its 1,800 °F maximum before it burns off?

The paste flux remains chemically active up to 1,800 °F; once the joint exceeds that temperature the flux is consumed and can no longer protect the braze.

Does the 5 lb jar produce noticeable fumes or heat during an all-day brazing session?

The flux itself generates no heat; any fumes come from the base metals and filler rod, so ventilation depends on the workpiece, not the paste.

Which filler alloys are required to work with this FB3-C classified flux?

It is formulated for high-silver and phos-copper brazing alloys, so you must supply a compatible silver or copper-phosphorus filler rod.

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