Although this article will provide 3 safe ways to weld aluminum, it should be noted that welding aluminum is not easy, especially for someone who does not do it for a living. Aluminum is a difficult material to weld because of the fact that it is so malleable and as a result welding will cause it to bend, warp, or not hold its shape. It is best when confronted with a project that requires you to weld aluminum to practice before attempting your final weld.
The three best ways in which to attempt to weld aluminum safely are to clean the surface of the aluminum, use a heat sink process when welding, and preheating the aluminum. Each of these methods should work to make the weld of your aluminum easier and safer. A reminder that before you attempt any weld of aluminum, always wear safety goggles and protective clothing.
Cleaning the Aluminum
Before you begin the process of welding aluminum, use an electric cleaner to completely clean the area where the weld will be applied. It is much more difficult to get a weld seam to hold when welding a dirty piece of material than it is to clean the piece thoroughly and completely before attempting the weld. Cleaning the aluminum will make it easier to work with and provide you with a better welding surface in which to accomplish the weld.
Use a Heat Sink
A heat sink is a process by which you clamp or secure the pieces of aluminum being welded to an attachment, made out of metal or copper. The heat sink helps keep the aluminum from warping because of the great heat conductivity that the aluminum is experiencing. The heat sink draws heat away from the aluminum pieces, allowing heat to be applied uniformly and evenly and makes sure that the weld is applied in the best possible way. If you do not use a heat sink, you will find in no time the aluminum piece either bending or shriveling and becoming unusable as a result of the intensive heat transfer.
Preheat the Aluminum Prior to Welding
Preheating the aluminum, particularly the area of the weld, will help you weld the seems safely and successfully. By preheating the aluminum prior to welding, you will find that it takes less time for the weld seam to come together. The less time that the seam is subject to being welded means the less heat that you will need to accomplish the weld.
Preheating can be accomplished by placing it in an oven or kiln to heat up to 300 to 400 degrees Fahrenheit or using an acetylene torch to apply heat directly to the weld area. If you use a torch, use a brushing motion so that the area doesn't singe or begin to warp as a result of the heat transfer. Once the preheating has concluded you should be able to apply the solder immediately.