How To Weld Aluminum With An Oxy-Acetylene Torch

by DoItYourself Staff

Oxy-Acetylene torches can be used for a variety of processes, and is one of the many processes that can be used to weld aluminum. Other processes that can be used to weld aluminum include TIG (Tungsten Inert Gas) welding, and MIG (Metal Inert Gas) welding. However, unlike TIG welding and MIG welding, Oxy-Acetylene, or arc welding, is a much more widely used process since it is relatively inexpensive and has equipment that is typically much more portable than TIG or MIG welding plants. Some of the disadvantages of using arc welding are the slag that is produced and the brittleness it may cause of the aluminum piece that is being worked upon. Using the Oxy-Acetylene is a good option if you are working on welding aluminum for the first time. You can accomplish the task by following a few simple steps:

Step 1: Set up The Equipment

The Oxy-Acetylene torch equipment is comprised of 2 separate tanks that will house the oxygen and acetylene gases respectively. After you ensure that the gas valves are turned off, hook up the hoses and tighten then securely using appropriate wrenches. Once these are tightened, you can open the individual gas valves to check the flow of the gases.

Step 2: Light Up The Torch

Use the regulators to adjust the flow of the gases to a starting position. This will usually require you to maximize the flow of acetylene and have the oxygen pressure set at about a quarter of the full pressure. You can then spark the nozzle and get the flame going. Adjust the regulator to bring the flame to a small blue flame, which will be optimal for welding use.

Step 3: Prepare the Work Pieces

Put on appropriate protective gear such as eyeglasses and gloves before beginning this process. It is recommended that you heat up the aluminum pieces before attempting any welding. This will help soften the aluminum and make it more amenable to welding. Once this is done, you should try to position the pieces to be welded as close as possible together on a flat surface using a jig. If you feel you can get a better fit of the pieces by using a file or grinding the pieces, it is recommended that you do so. Make sure that the metal is clean, dry and free of any grease or oil.

Step 4: Introduce the Filler Rod

Welding the pieces will typically require the use of a bronzing rod. You can place the rod on the seam of the aluminum pieces that you intend to weld and then work the torch flame on the filler by holding the flame a few inches above the rod. The rod will melt fairly quickly and form a metal pool to engulf the seam. The joint should have enough space to allow access for the metal pool to completely engulf the seam from both sides.

Step5: Cool Down

The last step of the process is to allow the work piece to cool down appropriately and to remove any slag build up by simply chipping away at it.