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Cupronil Fire Scale Preventive - Otto Frei
Otto Frei

Cupronil Fire Scale Preventive

Part # 154.390 138 In Stock Weight <0.1 lb / <5 g
$5.95
Select Size: 4 oz.

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Description

Cupronil Fire Scale Preventive is a combination flux and fire coat designed to reduce oxidation and help control solder flow during heating. Especially effective on sterling silver, it forms a protective barrier that minimizes fire scale while supporting clean, bright solder joints. Available in three sizes to suit bench jewelers and high-volume production alike.

Features

  • Combination flux and fire scale retardant in a single product
  • Highly effective on sterling silver; suitable for all non-ferrous metals
  • Acts as an anti-flux to inhibit solder flow to unwanted areas
  • Forms a protective white haze on the surface when properly heated
  • Ideal for soldering silver, gold, and other non-ferrous alloys

Available Options

Part # Size
154.390 4 oz (118 mL)
154.393 16 oz (473 mL)
154.395 1 Gallon (3.78 L)

Notes

How to use:

  1. Stir before use and keep the container closed when not in use.
  2. Apply a smooth, even coat to warmed metal using a spray or soft brush.
  3. Heat metal until Cupronil forms a white haze on the surface.
  4. Touch up any areas not fully coated.
  5. Solder as usual, then pickle, rinse, and polish.
  • For best results, apply evenly and avoid overheating the metal before the protective white haze has fully formed.

Specifications

Brand
Otto Frei
Part #
154.390
Type
Fluxes
Country of Origin
United States
Dimensions
4 in x 2 in x 2 in
Suitable Metals
Sterling silver and other non-ferrous metals
Composition
Copper, potassium, sodium borate, boric acid
Application
Sprayed or brushed onto warmed metal before soldering
California Prop 65 Warning California Prop 65 Warning:
Cancer and Reproductive Harm. www.P65warnings.ca.gov.

Reviews · 2

This product has 2 reviews.

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A
Anonymous
Great Product, Awesome Customer Service!

Same day shipping! Received it next day (I’m in the same state, but still!!)! Thank you!

C
Char Braun
Cupronil

This is a great product. You'll need to get a fine mist sprayer to spray to help prevent fires scale. (A sample size of hair spray that is emptied and cleaned out works great). I was taught to spray my solder (I use wire) works as flux