How to Weld Aluminum (with Pictures)

2024 Author: Samantha Chapman | [email protected]. Last modified: 2023-12-17 09:13

Welding is the process that involves joining two metal components by fusing them. Welding different materials is a difficult process, but when using light metals, such as aluminum, maximum precision is required in order to obtain a solid aggregation. To be able to weld aluminum you need to get the right tools, work with care and patience and gain experience. So, start collecting everything you need, learn the maneuvers that allow you to proceed with the welding and set up the space in which you will go to work.

Steps

Part 1 of 4: Collect the Supplies

Step 1. Get a TIG (tungsten inert gas) welding machine

It is a tool that uses a tungsten electrode and inert gas to protect the welding area. The accuracy achievable with this machine is critical when working with aluminum, especially with thin pieces.

TIG welding machines are expensive, so consider renting one. Contact the shops that make this type of equipment or hardware available to their customers to ask for information on any rental.
It is possible to weld aluminum with other processes, such as MIG welding, but the TIG method is the easiest and most suitable for beginners.

Step 2. Get the aluminum filler rods

It is the material that will join the two pieces. Do not use them if they are oxidized or dirty, as there is a risk that they will create weak joints.

You can buy them at a hardware store or home improvement store.
It is preferable that the alloy is 4043 or 5356.
Use a rod that is the same size as the tungsten electrode.

Step 3. Get an argon tank

Its purpose is to protect the weld. Pure argon is a cost-effective solution. You can add 3% helium to increase its stability.

Gas must be purchased from authorized distributors. Most shops that sell welding products can provide it to you or tell you where to buy it.
If you decide to rent the TIG welding machine, buy an argon cylinder at the same time.

Step 4. Wear protective clothing

Wear a long-sleeved shirt of thick fabric. TIG welding produces a large amount of ultraviolet radiation. Additionally, you may get burns on your arms using short-sleeved clothing.

Put on a 100% cotton shirt.
Make sure your pants don't have tucks that can hold pieces of molten metal.

Step 5. Use the safety devices

Wear a sturdy welding helmet, a pair of double gloves and a respirator to protect yourself while working. This equipment will defend you from bright light, radiation, chemical burns, fumes, oxides, electric shocks and other possible inconveniences.

Welding gloves must be insulating and fireproof.
Keep a fire extinguisher handy in case of stray sparks.
For welding it is preferable to choose a helmet with a photochromic lens. It should have a degree of darkening between 10 and 13.

Part 2 of 4: Setting up the Workspace

Step 1. Clean the aluminum

Over time, this metal forms a light oxide patina on the surface that melts at much higher temperatures than aluminum itself. For this reason, before proceeding to soldering, you must first clean it of oxide. Use a wire brush, sandpaper, or file.

Spray an electrical component cleaner on the parts to be joined. Rinse the piece of aluminum in the water and let it dry thoroughly. Pass the steel wool to complete the cleaning

Step 2. Clean the filler rods

If they are dirty, they can contaminate the weld like any dirty piece of metal. Use an abrasive sponge to make sure they are not covered with contaminants.

Step 3. Make the pieces fit together as best as possible

TIG welders do not forgive if the contact between the two metals does not allow a strong adhesion. In this case, the weld will be defective. Then, make sure they fit together as best as possible by joining them with zip ties and clamps.

Consider sticking them in a heat sink, for example made of copper. It will ensure that the heat produced by the weld is transferred without creating inconvenience, ruining the work or damaging other elements present in the area where you are operating

Step 4. Preheat the aluminum

Soldering will be much easier if you work with a piece that is warmer than room temperature. You can heat it by placing it directly in an oven or by using a propane gas torch to distribute the heat over the surface. The temperature must reach between 150 and 200 ° C.

If you have to join large pieces of aluminum, the weld may be weak or inconsistent if you don't heat them first

Step 5. Work in a safe, airy and cool environment

When you're ready, first make sure you have a fire extinguisher on hand in case a fire breaks out while working. Also, you should choose a place with a temperature below 25 ° C and good air circulation, to prevent heat stress and avoid inhaling dangerous fumes.

You can also protect yourself from harmful vapors by using vacuum cleaners suitable for sucking up the fumes produced by the welding process

Part 3 of 4: Learning the Welding Maneuvers

Step 1. Hold the flashlight with your hand

While practicing, keep the flashlight off to avoid wasting metal. Put on your gloves and place one hand on the table for more support. Hold the flashlight at an angle of approximately 10 degrees, keeping the tungsten tip approximately 6-7mm away from the aluminum.

If you position the tip too far, the spreading arc will be too large and you will have a hard time controlling the weld

Step 2. Tilt the wand 90 degrees

You must advance the weld with the welding rod by holding the welding rod at an angle of approximately 90 degrees to the tip of the torch. The flashlight must always be pushed, never dragged.

If the rod and tip come into contact, the weld will be contaminated and will lose its structural integrity

Step 3. Move the torch along the area to be welded

With the torch in the correct position, practice moving your hand along the part of the aluminum you intend to weld. Practice with gloves, so you have a better idea of the effort you will need to put into it. Make sure you move your whole hand because if you get into the habit of using only your fingers, your movements will be limited.

Part 4 of 4: Solder the Metal

Step 1. Adjust the amperage of the welder

Try to use 1 amp for every 0.025mm thickness of the workpiece you need to work with. It is a good idea to set the amperage higher than necessary and then adjust the current by lowering it with the footswitch.

Step 2. Put the tools and the piece of aluminum in place

Start by holding the tungsten electrode no more than the diameter of the torch nozzle. For example, if you are using a 6mm nozzle, the tungsten tip should be no further than 6mm from the nozzle. Bring the tip of the electrode into contact with the workpiece, then move it away about 3 mm.

Step 3. Press the button on the flashlight

If there is a button to press on the flashlight, you will need to squeeze it to create the electric arc. It will activate the high frequency start function, as it is connected to a cable that is in turn connected to the power supply of the TIG welding machine. This is the simplest way to create the bow.

Step 4. Use the pedal

If the flashlight does not have a button, you must create the arc with the pedal. Press it at least halfway, so you get the bow.

If you are having difficulty activating the arc, the amperage is most likely too low. Adjust it and try again

Step 5. Create the weld pool

Melt the piece of aluminum until you have a weld pool of sufficient size, i.e. no larger than twice the diameter of the rod. Add the right amount of filler material to fill the seam, then continue along the part to be joined. Continue until the weld is finished correctly.

As you go, the metal will heat up. Use the foot pedal to decrease the amperage to maintain control of the weld pool.
When casting, pay close attention to the size of the bath. If it is too big or too small it could burn the material or weaken the weld.

Step 6. Squeeze the weld pool

Apply light pressure on the weld pool that forms under the joint, adding the filler metal as you go. Move it at a constant speed, so that the dimensions remain the same.