Exclusive Kapp Alloy Products:

KAPPFree
KappFree solder is a lead-free formulation designed specifically to replace lead solders in plumbing, electrical and electronic applications.

KAPPRAD
Lead-free solder for fast strong repair of aluminum & aluminum-copper radiators and a/c coils.

GALVANITE
Lead-free solder for high quality repairs to galvanized steel surfaces.

ALUMITE
The original fluxless solder for aluminum.

DURAKAPP Babbitt
Higher strength and ductility babbitt improves bearing performance & extends bearing life.

KAPP Tec
High temperature, high-strength solder for metals other than aluminum.

KAPP TecZ
High temperature, high strength solder that may be used on most metals, but especially aluminum, copper and stainless.
KAPPRAD™
THE Radiator Repair Solder

KappRad™ has been developed specifically to join and repair aluminum and aluminum/copper radiators and heat exchangers. A lower melting point makes delicate repair work easier. Matching KAPP Golden Flux acts as a temperature guide to ensure simple application and successful bonding.

KappRad™ can use any heat source - oxy-acetylene, natural gas or propane torch, heat gun, or soldering iron. It can be used on aluminum, stainless steel, white metal, pewter, copper, brass and galvanized. In addition, it can be plated with chrome, nickel or copper.

Physical Properties & Technical Data
Composition 40%Sn - 27%Zn - 33%Cd
Liquidus 500°F - 260°C
Solidus 350°F - 176°C
Density 7.643lbs./cu. in.
Electrical Conductivity 23 (% IACS @ 68°F)
Shear Strength (copper) 11,000 psi @ 72°F
Tensile Strength Up to 20,000 psi
 

*Note: Shear strengths based on double lap joints, Tensile strengths depend on base metals, soldering methods and type of joint.

Successful Soldering with KappRad

  1. Pre-clean the parent metal or metals to be joined. Use emorycloth, a wire brush, sandblasting, etc. Prepare aluminum surfaces with a stainless steel wire brush.
     
  2. Apply Kapp's noncorrosive liquid Golden Flux to the repair area. You may easily use the rod to apply the flux.
     
  3. Use a soft flame, heat gun or soldering iron to heat the parent metal adjacent to the repair area. A direct flame on the repair area is likely to overheat the solder and flux.
     
  4. Hold the torch tip 4 to 6 inches away from the parent metal. If it is necessary to apply the flame directly to the rod or flux, pull the torch tip back even farther from the work surface and keep it moving.
     
  5. The flux will begin to bubble and turn light brown. Besides preparing the parent metal for the solder, these changes indicate the proper working temperature. If the flux turns black, let the area cool, clean it up and start over.
     
  6. When the flux turns brown, it is time to apply the rod. Drag the rod over the area to be soldered until it begins to flow. STOP APPLYING THE HEAT! If additional layers are needed, continue to drag the rod over the area.
     
  7. Sometimes it is necessary to heat the tip of the rod with the flame to help the solder flow easier and quicker onto the repair area.

    DO NOT HEAT THE ROD TO THE MELTING POINT!
     
  8. Observe the solder deposit. The solder should bond smoothly. DO NOT OVERHEAT! The rod will melt if overheated, but will not bond properly.
     
  9. If you stopped soldering and want to apply more solder or flow out the deposit more, add more flux and reheat. The flux will help the bonding process, whether adding more rod or just flowing out the previous deposit.
     
  10. Remove the excess flux with warm water and a wire brush.

 


Copyright © 2004 Kapp Alloy and Wire, Inc. All rights reserved. Information in this document is subject to change without notice.
Other products and companies referred to herein are trademarks or registered trademarks of their respective companies or mark holders.