How to Weld Brass: Complete Beginner’s Guide

Using MIG welding, TIG welding, or flame welding technique, you can eld brass to brass or other metals. The brass must be cleaned to remove oils that make the weld more porous and less stable. 

Brass is a common choice for various applications due to its unique properties. It conducts electricity well, offers good corrosion resistance, and produces less friction. Yet, it’s not the easiest metal to weld.

Can You Weld Brass?

You can weld brass using a variety of techniques, including MIG welding. Brass has a low melting point compared to steel and iron. A lower melting point makes brass easy to fuse, but there is more to consider.

I find that welding brass poses a few challenges that can weaken the weld. Zinc is the root cause of the potential concerns when welding brass.

You need to look at the zinc content of the brass before welding. Brass with a lower zinc content is easier to weld compared to brass with a higher zinc content. 

Brass is comprised of about 66% copper and 34% zinc. Zinc has a lower melting point than copper and evaporates quickly when welding.

The evaporation of zinc makes the brass more porous. It reduces the strength of the metal and the weld. 

Zinc also produces more toxic fumes when melted. Air ventilation and protective equipment are needed to protect yourself. 

You should also use gas shielding to protect the workpiece. Gas shields zinc from the atmosphere. This can decrease the risk of porous welds.

Required Equipment

The main pieces of equipment needed for welding brass include:

• Filler wire
• Shielding gas
• Personal protective equipment (PPE)
• Cutting instrument
• Abrasive cleaner
• Vise/clamps

Along with these items, you need a welding machine of some type, such as a MIG welder or a TIG welder. 

Welding Types Suitable for Brass

The following are the most suitable types of welding for working with brass:

• MIG welding
• TIG welding
• Flame welding

You can also solder brass. However, soldering and welding are two separate processes. 

Soldering involves the use of a filler metal with a very low melting point. The solder is melted between the workpieces. 

With welding, the workpieces are heated and fused. Welding requires a much higher temperature. Welding also produces a stronger joint, making it ideal for joining brass with brass or other metals.

You can weld brass to brass and most other metals, but a different technique is recommended for welding brass with steel. Instead of welding brass to steel, consider brazing. 

Steel and brass have major differences, including different melting points. Brazing uses lower temperatures to melt a filler metal.

How to Prepare Brass for Welding

You can weld brass to brass and other metals. Yet, you need to prepare the material to produce the best results. Preparing the brass may involve several steps depending on the project:

• Cutting brass
• Bending brass
• Cleaning brass

You’ll also need to prepare the work area. Remove any flammable or combustible materials. 

After preparing the work area, complete the following steps as needed.

Cutting Brass

You may need to cut brass rods, wire, tubing, or sheets for your project. Use a vise to secure the brass before cutting. 

The type of brass you want to weld may require a specific cutting instrument. 

Use cutting pliers, a hacksaw, or a handheld rotary tool to cut brass rods. You can also use a pair of pliers or wire cutters to cut brass wire. 

Use a saw or a tube cutter to cut brass tubes. Pliers and wire cutters are more likely to crimp the ends of the tube.

Hacksaws and metal shears work best for cutting brass sheets. I typically place a piece of plywood on each side of the metal sheet when securing it to the vise. The wood ensures a better grip.

Bending Brass

Bending the brass may be necessary. You may bend brass wire or thin brass tubing using a pair of pliers. Needle-nosed pliers are useful for creating tight bends. 

A bending jig is recommended for bending heavy brass rods and wires. A bending jig is simply a clamp that holds the workpiece as you bend it to the desired shape.

The typical bending jig is made of several sheets of stacked plywood. Holes are drilled to hold metal pegs for securing the workpiece. The jig is then clamped to your worktable. 

Bending brass tubing is more difficult. Mistakes could create kinks or crimps in the tubes. A spring bender can help you bend the tube without crushing it. 

Cleaning Brass

Clean the brass after cutting and bending it. You need to remove any contaminants, coatings, and chemicals. Any debris can limit the quality of the weld. 

Grease and other contaminants can increase the porosity of the joint where you fuse the two metal pieces. The connection may become brittle and break easily.

Use an abrasive cleaner to scour and thoroughly clean the brass’s surface. Rinse residue away with water. 

Use alcohol to give the brass workpieces a final rinse. Alcohol helps remove any lingering oil and debris. It also dries cleanly. 

Filler Wire

Filler wire is used for MIG welding and TIG welding brass. Copper-based filler wire is typically used with brass. Common options include:

• Copper and 3% silicon
• Copper and 7-12% tin
• Copper and 8% aluminum

I’ve found that you won’t perfectly match the color with a filler wire due to the lack of zinc. Copper with tin is often used due to its color compatibility with brass. Copper with aluminum is also a good choice for getting a closer color match. 

Shielding Gas

Most welders use 100% pure argon or a mixture of argon and carbon dioxide for the shielding gas. Using a shielding gas protects your materials from exposure to the environment. 

Oxygen from the environment can create zinc oxide as the zinc in the brass evaporates. Zinc oxide is harmful but easy to avoid with the right shielding gas and personal protective equipment.

Personal Protective Equipment

Wearing proper personal protective equipment is also necessary. You need protection for your eyes, face, skin, and hands. 

A welding helmet, safety goggles, flame-retardant clothing, and gloves are common forms of PPE for welding. You should also wear a respirator when sanding metal coated with paint or rust. 

Cutting Instrument

You’ll likely need to cut one or more pieces of brass before welding. Hacksaws, pliers, wire cutters, shears, rotary tools, and angle grinders are commonly used to cut metal. 

Abrasive Cleaner

Abrasive cleaners and materials, such as a file, sandpaper, and scrubby pads, can remove residue from the surface of the brass. Some brass materials also come with a clear lacquer coating, which you need to remove with an abrasive cleaner.

Vise/Clamps

Vises, clamps, and bending jigs are useful pieces of equipment for securing your materials. You may need to hold a piece in place before welding to ensure a proper fit. 

How to MIG Weld Brass

Metal inert gas (MIG) welding is a suitable option for welding brass. It’s a type of arc welding that involves the use of filler metal to help join two pieces of metal together.

The base metal and the metal that you want to attach are held in place with clamps or pins. A metal wire acts as the filler metal. 

The MIG welder continuously feeds the filler wire through a contact tube. The trigger from your welding gun forms an arc between the wire and the workpiece. 

Consider preheating the brass when welding thick sections. Preheating the brass to about 212 degrees Fahrenheit (100 degrees Celsius) can minimize the evaporation of zinc when welding.

The formation of zinc oxide is one of the main concerns when using MIG welding for brass. Shielding gas minimizes this hazard. 

Common recommendations include a 75/25 argon/carbon dioxide mixture or a 100% argon gas. The gas limits zinc oxide production and creates a barrier that can keep fumes from escaping your work area.

Working in small intervals can also help when welding brass. Instead of a continuous joint, use the stitching technique. Complete small welds and allow the weld pool to cool before continuing. 

Using smaller stitches instead of a continuous line keeps the metal from being continuously exposed to heat. This limits the evaporation of zinc and helps ensure a stronger joint. 

How to TIG Weld Brass

TIG welding works well for brass but requires more experience. It offers greater precision compared to MIG welding. It’s also less forgiving compared to MIG welding.

Overheating the work area is more of a risk with TIG welding brass. The zinc may flow over the electrode wire. Pausing your work every few seconds can help you avoid these issues.

You should also leave the shielding gas flowing for a short period after finishing the weld. Leaving the gas on momentarily helps the weld pool cool before exposing it to the atmosphere.

How to Flame Weld Brass

Flame welding allows you to use a welding torch to solder two pieces together instead of fusing them. The torch melts the solder, binding to the metal you want to combine. 

Using a soft solder can help prevent discoloration of the brass. Softer solder has a lower melting point, which limits the heat you need to apply to the brass. 

Along with solder, you need flux. Flux paste directs the solder and keeps it from flowing beyond the joint.

You also need to select the right type of flame. There are three basic types of flames: 

• Natural flame (neutral flame)
• Carburizing flame
• Oxidizing flame

An oxidizing flame is the most common choice for working with brass, copper, and zinc. Here’s a closer look at each of the three options.

Neutral Flame

Neutral flames, sometimes called natural flames, burn the fuel completely. These flames don’t produce a chemical effect. 

A neutral flame is typically achieved when the mixed gas contains about one part oxygen to one part acetylene. 

Neutral flames are often used when welding mild steel, stainless steel, aluminum, and copper. This type of flame is also commonly used to preheat metal, as it has a lower temperature than other flames. 

Carburizing Flame

Carburizing flames contain excess fuel gas. It reacts chemically with the metal to create metal carbide. 

Carburizing flames contain more acetylene and achieve a higher temperature compared to a neutral flame. It can boil the metal and significantly reduce the quality of your weld. 

Oxidizing Flame

An oxidizing flame is a preferred choice when welding brass with a flame. It achieves a higher temperature but contains more oxygen. 

The presence of oxygen makes it less ideal for welding steel, but it’s still a good choice for brass. The oxygen level helps create an oxide film on top of the molten metal. The oxide layer decreases the vaporization of zinc. 

Applying Flux to Brass

Applying flux to brass is often recommended when using flame welding. The solder wire will travel anywhere that you place the flux. It helps you maintain a clean seam.

Apply the flux with a thin piece of wire or stick. You only need a small amount to cover the area where you intend to melt the solder.

Prepare the Solder 

Solder wire for flame welding is often thick. Flattening it with a hammer can make it easier to work with.

Flatten the solder and place it directly where you want to join the two pieces of metal. Secure your pieces with clamps or pins.

Turn on your torch and adjust the gas to achieve the desired flame. As mentioned, you’ll likely want to achieve an oxidizing flame to prevent the vaporization of zinc.

When you’re ready to solder, heat the metal workpieces instead of the solder. As you heat the metal, the solder will melt and flow along the flux. 

Conclusion

You can weld brass to brass and other metals. Brass has a lower melting point compared to many other metals and contains a high zinc content. The zinc can evaporate when welding, limiting the strength of the joint and the metal. 

By working in smaller sections, you can avoid creating a brittle, porous joint. Let the metal cool occasionally, whether you use MIG welding or TIG welding. You can also flame-weld brass to other metals using solder and flux.