How to Braze Aluminum at Weld Strength

This video explains how to braze aluminum and attain weld strength.

An aluminum tail light housing with a sizeable hole is brazed with Super Alloy 5 aluminum repair kit and an oxy-MAPP gas torch.  Due to the size and thickness of this aluminum part, propane or straight MAPP gas with a trigger start tip could be used just as effectively.  Larger or thicker aluminum pieces will require more oxygen to reach Super Alloy 5’s 600°F working temperature.

First, remove the oxidation from the aluminum part using a sanding disc, sandpaper, wire brush or wire wheel.   If you’re unable to remove all the oxidation, don’t worry.  Super Alloy 5’s unique flux will eliminate the remaining impurities to expose the parent metal.  Removing the oxidation prior to brazing simply enables you to use less flux on the repair.

Once the aluminum tail light housing has reached 600°F, heat the end of the aluminum brazing rod and dip it into the flux jar.  This will adhere the flux to the rod for proper application.

Apply the flux to the part, then build a bridge across the hole by laying a piece of the aluminum brazing rod over the gap until the hole is completely covered.  Continue adding flux, which bonds the rod to the parent aluminum and smooths out the filler material.  If you notice any low areas, apply more rod.  Be sure to keep the torch moving to avoid overheating the aluminum or remelting the filler rod.

Use of Super Alloy flux is superior to flux-less alloys for many reasons:

  1.  Cleans while it works
  2.  Creates a stronger bond
  3.  Seals holes and cracks
  4.  Acts as an absolute temperature guide, becoming liquid when the part has reached 600°F

After completing the braze, allow the part to cool naturally.  When the part has cooled, Super Alloy 5 flux residue can be easily removed with a wire brush.  The original part can then be powder coated, painted, polished, drilled, tapped, bent, threaded, anodized or machined.

 

NotePlease observe all AWS Safety & Health Guidelines when using Muggy Weld products.