Sculpting out of junk metal poses the question of what is the best method to connect different types of metal. Several different techniques can be used to connect the junk metal pieces such as brazing, welding, screwing, wire bending and metalsmithing. The best way to connect different types of junk metal together is by using the brazing technique.
Found or Junk metal
Fluxed brazing rod
Step 1 – Collect the desired junk metal or found metal objects to create the art sculpture. Start the sculpture by experimenting with the pieces to form the desired sculpture shape. Clamp together the largest piece of metal with the next desired piece. Place it on a flat safe surface to braze. Lightly sand or wire brush the area to be brazed before clamping to remove any patina or dirt.
Step 2 – Position the clamped pieces of metal together so as much of the seam area can be seen. Put on the welding mask.
Step 3 – Open the acetylene fuel valve to allow only a small amount of fuel into the torch line. Light the torch. Adjust the acetylene flow to the desired intensity. The flame should be a consistent blue color without yellow fluctuation.
Step 4 – Heat the area to be brazed until it begins to glow. Touch the tip of the brazing rod to the seam until it begins to flow. Slowly pull the rod along the seam in the opposite direction of the flame. Drag the flame overly the newly brazed seam to create the seal.
Step 5 – Turn off the flame to the torch. Allow the seam to cool then inspect the area for a seam that has no cracks, bubbles or indentations. Repeat the brazing process if any imperfections are seen in the brazed seam.
Step 6 – Continue adding pieces to the junk metal art sculpture in the same manner.
A newly lit acetylene torch will burn with a black smoke trail. The black smoke will subside as the proper amount of oxygen is introduced into the mixture. Begin the brazing process after the black smoke has stopped.
Brazing should not be attempted by someone who is not familiar in working with an acetylene torch. The process is dangerous if the proper mixture of acetylene and oxygen is not attained.
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