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Copper Solder Paste - Soft - 1/2 oz - Cadmium Free

Part # 154.840 36 In Stock Weight -- lb -- g
Current price $5.95

This copper paste solder — technically known as phos-copper paste solder — is a cadmium-free and indium-free formula designed for hard (torch) soldering applications. Sold in a convenient syringe containing 10 DWT (1/2 troy ounce) total weight, it is well suited for jewelers, metalsmiths, and fabricators working with copper, brass, bronze, and mixed-metal projects.

Phos-copper paste solder flows at 1325°F — approximately the same temperature as a soft silver solder — making it accessible for a wide range of torch setups. The alloy produces a light brassy color upon completion, blending naturally with brass and copper-toned metals. It has a long history of use in producing brass military belt buckles and similar fabricated brass components.

This paste is especially useful for mixed-metal work, including silver to brass and stainless steel to brass or gold joints, expanding its versatility beyond single-metal projects.

Note: The date printed on the syringe is the manufacturing date — it is not a sell-by or expiration date.

Caution: Contains Fluorides.

Features

  • Cadmium-free and indium-free formula
  • Flows at 1325°F — comparable to soft silver solder
  • Produces a light brassy color finish
  • Suitable for copper, brass, bronze, and mixed-metal projects
  • Compatible with silver-to-brass and stainless steel-to-brass or gold joints
  • Convenient syringe format for controlled application
  • For hard (torch) soldering only

Specifications

Type Phos-Copper Paste Solder
Flow Temperature 1325°F
Grade Soft
Net Weight 10 DWT (1/2 troy oz)
Format Syringe
Cadmium Free Yes
Indium Free Yes
Soldering Method Hard (torch) soldering only
Finish Color Light brassy
Safety Note Contains Fluorides
California Prop 65 Warning California Prop 65 Warning:
Cancer and Reproductive Harm. www.P65warnings.ca.gov.
Brand
Otto Frei
Part #
154.840
Type
Solders
Dimensions
9 in x 2 in x 1 in
Flow Temperature
1325°F
Grade
Soft
Net Weight
10 DWT (1/2 troy oz)
Format
Syringe
Cadmium Free
Yes
Indium Free
Yes
Soldering Method
Hard (torch) soldering only
Finish Color
Light brassy
Safety Note
Contains Fluorides