One of the most popular questions is, “What’s the best welding output for my job?” This is a difficult question, as different welding applications need different outputs.
As such, we’ve broken it down into the most common welding scenarios and what’s the best welding output for them.
1. Metal Fabrication: We recommend 1-6 amps per foot of welding for metal fabrication, depending on the application. A typical metal fabrication shop will weld between 50 and 150 feet a day, so it’s based on the type of application and how many times the welding will occur during the project. This can be a huge number if you have very complex applications.
For example, if you have a large ship hull with many complex shapes, you’d want to use high amps to get good penetration and a smooth finish. In the case of metal fabrication shops that do a lot of work with stainless steel, the higher amperage welding provides better welding speeds and good penetration.
2. Manufacturing: We recommend 2-6 amps per foot of welding. This is mostly used when welding steel but can apply to stainless steel if you have multiple passes required.
3. Heat Treating: We recommend about 4 amps per foot of welding for heat treating, but this can vary depending on the application.
4. General Maintenance: Experts recommend about 6 amps per foot of welding for general maintenance.
5. Repair: We recommend 6-12 amps per foot of welding for repair welding. This is mostly used when welding stainless steel or aluminum and thin welding sheets of steel.
6. Fabrication: We recommend about 10 amps per foot of welding for fabricating. This is typically used for thicker pieces and to minimize distortion.
7. Hot Work: We recommend about 16 amps per foot of welding for hot work. This is used when welding stainless steel, aluminum, and thicker steel plates.
8. Spot Welding: We recommend about 20 amps per foot of welding for spot welding. This is the highest current setting for a typical welding gun.
What Welding Output To Use?
For metal fabrication, welds will typically range from 1-8 amps per foot, depending on the thickness of the plate and the type of joint. Welds should be performed at no less than 1 amp per foot and no more than 8 amps per foot. You should start with the low end and work your way up from there.
In the case of heat treating, welds will typically be around 2 amps per foot. You can increase the current to 3 amps per foot as you get to thicker areas. However, this can lead to spatter and distorted joints. So again, starting at the lower end and increasing as needed can help keep welding safe.
For manufacturing, welds will typically be around 3-10 amps per foot. Welds should be performed at no less than 3 amps per foot and no more than 10 amps per foot.
For heat treating, welds will be around 5 amps per foot. You can increase the current in thicker areas.
For general maintenance, welds will be around 6-20 amps per foot. Welds should be performed at no less than 6 amps per foot and no more than 20 amps per foot.
For repair welding, welds will be around 10-50 amps per foot. Welds should be performed at no less than 10 amps per foot and no more than 50 amps per foot.
For fabrication, welds will be around 10-200 amps per foot. Welds should be performed at no less than 10 amps per foot and no more than 200 amps per foot.
For hot work, welds will be around 25-150 amps per foot. There should be no less than 25 amps per foot of welding and no more than 150 amps.
For spot welding, welds will be around 50-400 amps per foot. Welds should perform at no less than 50 amps per foot and no more than 400 amps per foot.
When using welding equipment, you must follow the machine’s instructions to ensure you’re in the right mode for the application.
Welding Process and Amperage Selection
Most of us are familiar with welding processes at home and work. We might have even done a bit of welding in the past. However, we may not know exactly what welding is. Welding is a process of combining pieces of metal using heat and filler material. There are different types of welds, and a person must understand the different types before doing the welding process.
There are three main types of welding:
2. Gas metal arc
3. Shielded metal arc
Each type has a different amperage range, and the wrong welding method can damage the welded components.
The three main types of welding are used when welding metals and plastics. In the metal-arc welding process, an electric arc is created between two electrodes containing filler material. When the current passes through the filler material, it heats it, fusing it into place. The filler material is usually a combination of metals, but the filler could also be plastic, ceramic, and composite materials.
Gas Metal Arc Welding
The gas metal arc welding process uses a plasma of gases to produce the electric arc between the electrodes. The filler material is metal or composite, such as fiberglass and carbon fiber.
Shielded Metal Arc Welding
The shielded metal arc welding process is where the filler material is added after the electrical arc is created. This welding process places a non-conductive shield over the welding area to prevent the filler material from being melted into the substrate.
Pro Tip: Using the correct welding method is very important when welding. When welding, ensure you have the right amperage and type of welding machine. If you are welding in your home, you may consider getting a gas or electric welder instead of a MIG welder.
With a MIG welder, the filler material is placed on the tip of the electrode wire, which is attached to the welding machine. With a gas or electric welder, the filler material is added directly into the molten metal and does not need the help of the electrode.
Welding with the right amperage, type of welding machine, and the correct welding process will greatly reduce the chances of damaging the welded components. Make sure you read the welding machine’s manual before starting the process.