It can be incredibly frustrating when your helmet lens fogs up. It’s something we’ve all had to deal with, and something I’m sure we’d rather not deal with again.

If you’re wondering how to keep your welding helmet from fogging, making sure the helmet seals are in good shape is a great place to start. Proper seals help the helmet fit snugly on your head and aid ventilation, which can prevent the lens from fogging up. Combine this with anti-fog products and regular cleaning, and fogging should not be an issue.

I’ll touch on a few more reasons you may see fogging and a few other solutions in case the above just isn’t cutting it!

What Causes of Fogging In Welding Helmets?

Before you learn how to prevent and fix fogging, it’s important to understand what causes it in the first place. Otherwise, we’ll be fighting a battle we don’t fully understand.

Fogging is caused by the combination of heat and moisture. The inside of your helmet can become humid as you breathe, sweat or are exposed to high levels of environmental humidity. This humidity can cause the lens to fog up, making it difficult to see. Fogging is a real a pet peeve of mine as it can totally disrupt your session and focus.

Another reason for fogging can be the temperature difference between the inside and outside of the helmet. If the temperature outside is colder than the inside temperature, the moisture inside the helmet may condense on the lens, causing fogging.

If you wear glasses, you know the pain of walking into an air-conditioned building in summer and losing all vision pretty fast, this is the same concept.

It’s also important to know that not all welding helmets are created equal. Some will be more prone to fogging than others. Cheap, poorly made, or older/ worn helmets may not have proper ventilation or anti-fogging features, making them more susceptible to fogging than others.

So, a quick fix is to invest in a good-quality helmet!

How to Prevent Fogging in Welding Helmets

Preventing fogging in your welding helmet is vital to maintaining a clear, safe view while welding. Here are a few techniques you can use to keep your helmet lens clear:

Keep the helmet clean and dry:

This may seem obvious, but it’s an important step in preventing fogging. Regularly clean the inside and outside of your helmet with a dry cloth or compressed air to remove dust and debris. A boring answer, but so important!

Use anti-fog products specifically designed for welding helmets:

These products can help reduce the amount of moisture inside the helmet, which will reduce the likelihood of fogging. They can come in sprays, gels, or wipes and can be applied to the inside of the lens before use.

Ensure proper ventilation by keeping the front and back vents open and unobscured:

This will allow air to flow freely through the helmet, helping keep the inside dry and getting rid of that excess moisture which can cling to the lens.

Adjust the helmet to fit snugly on your head:

This will prevent air from entering the helmet, which can contribute to fogging. Ensure the helmet is adjusted correctly and sits securely on your head. The last thing you want is to feel like you’re welding in a sauna.

Use a fan to direct air into the helmet:

This can help to keep the inside of the helmet dry and reduce the likelihood of fogging. This may not always be an option, but it’s great for jobs in enclosed areas when possible.

These techniques can help reduce the chances of your helmet lens fogging up, but as your jobs (and therefore surrounding environments) will likely vary, here are some quick tips to deal with fogging just in case the above don’t work.

3 Quick Fixes for Welding Helmet Fogging

Ok, so you’ve tried the above, and now you’re on a job and are still getting issues with fogging.

Even with the best preparation, fogging can still happen. It’s important to have quick fixes on hand to clear the lens and get back to welding safely. Here are a few things you can do in a pinch when your helmet lens fogs up:

1. Use a clean, dry cloth to wipe the inside of the lens. This can help to remove any moisture or debris that may be causing the fogging.
2. Use a defogging solution or spray to clear the lens. These products can help to break down the moisture on the lens and clear it up quickly. (I always keep a bottle of this handy on a job!)
3. If possible, use a fan to direct air into the helmet. This can help to keep the inside of the helmet dry and reduce the likelihood of fogging.

It’s important to note that these quick fixes are just that, quick.

They’re meant to provide a temporary solution until you can properly address the cause of the fogging.

If you find yourself constantly having to use these quick fixes, it’s a sign that you need to take a closer look at your helmet and maintenance routine.

Frequently asked questions

How do I stop my welding hood from fogging up?

The best way to stop your welding hood from fogging up is to ensure that you have proper ventilation through the helmet. If this does not help, you can also try products such as anti-fog spray, or look into buying anti-fog lenses or a specially designed face shield with built-in anti-fog technology.

How do you use anti-fog spray on welding helmets?

To use anti-fog spray, you’ll first need to clean the inside of your welding helmet with a damp cloth, and then let it dry completely. Then, spray the inside of the lens with the anti-fog solution, making sure to avoid any contact with your skin or eyes. Let the solution sit for a few minutes, and then use a soft dry cloth to polish off any excess solution. After the helmet has dried completely, it should be ready for use.

How do you clean the inside of a sweaty helmet?

Sweaty helmets can be a breeding ground for bacteria. To stop it from smelling, you’ll need to clean it regularly. First, remove the sweat-soaked padding and wash it with mild detergent in warm water, then let it air dry. Once the padding is dry, you can clean the inside of the helmet with a damp cloth or sponge using mild soapy water. Make sure to rinse the helmet thoroughly and dry it with a clean cloth or let it air dry before replacing the padding.

Conclusion

So, you can avoid fogging in most circumstances by simply keeping the helmet clean and dry, adjusting the helmet to fit snugly on your head, and making sure the seals are sound.

But let’s be real, sometimes fogging can happen anyway, so it’s always good to have quick fixes on hand, such as using a clean, dry cloth to wipe the inside of the lens, using a defogging solution or spray, keeping a spare lens, or using a fan to direct air into the helmet.

A clear lens is crucial for a safe welding experience, so make sure to maintain your helmet and address fogging properly. After all, some jobs are tough enough, so the last thing you want to worry about is being able to see what you’re doing!

Welding is a hot topic (pun intended) and a crucial process in many industries. But one question that often pops up is, “Can you touch the metal you are welding?”.

Well, it’s not as simple as you might think. With regards to arc welding, Although you won’t be electrocuted by touching the work, it is not advisable to do so with any exposed skin due to potential UV/IR radiation and the obvious heat. When it comes to MIG & TIG welding, the general rule of thumb is not to touch it at all without protective gear.

Ready to get down and dirty with the details of welding safety? Then don your protective gear and let’s do this! In this article, all shall be revealed about welding safety – no more burning questions (pun totally intended)!

The Dangers of Touching Metal While Welding

Touching metal while it’s being welded is like playing a game of “Hot Potato”, except the potato is a red-hot piece of metal, and you’re the potato. Not a game you want to win, trust me.

The heat generated during the welding process can cause serious burns and electric shocks. Imagine getting a tan, but not in a good way, in the “I just got burned” way.

Not pretty.

Plus, if you’re not careful, you could end up with a permanent “Welding mark” on your hand, and who wants that?

Protective gear and safety precautions are crucial to prevent accidents, so make sure to put on your gloves and helmet before you start welding.

Techniques for Avoiding Contact With Metal While Welding

Welding can be a tricky business, but there are ways to avoid touching the metal while you’re welding.

For example, you can use tools or clamps to hold the metal in place so you don’t have to burn your fingers.

You could also try using the correct electrode, shielding gas, and welding torch, which can help prevent contact.

Additionally, proper training and following safety protocols can also help you avoid any accidents.

Remember, prevention is better than cure, especially when it comes to burns and electric shocks.

Before you begin welding, ensure that your arsenal is complete with all the appropriate equipment and information to maintain a safe work atmosphere.

Can You Touch The Electrode While Stick Welding

When it comes to stick welding, the electrode is essential for successful results. It’s important to understand if you can touch it or not in order to achieve a successful weld.

The answer is no. 

The electrode is the conductor that carries the current, and it can cause serious injury if touched while it’s live.

In order to prevent electrical shock, the electrode must be handled and maneuvered with specially designed holders or gloves made from an insulated material. These holders or gloves provide a protective barrier that allows welders to work safely and securely.

It is also essential to be aware that the electrode can become extremely hot during the welding process, so even if you don’t touch the electrode directly, it’s still possible to burn yourself if you’re not careful.

When working with the electrode, it is essential to wear gloves and adhere to the instructions of the manufacturer for utmost safety.

Why Does my Welder Shock Me

Feeling a shock while welding is not uncommon, and it can happen due to several reasons.

One of the main causes is poor grounding. If the welder is not properly grounded, the electrical current can travel through the welder and into the operator, causing a shock.

This can be easily prevented by making sure the welder is properly grounded and connected to an appropriate power source.

Another cause of welding shock is poor insulation on the electrode holder or welding cables. If the insulation is damaged or worn, it can allow electrical current to pass through and shock the operator.

To prevent this, make sure to regularly check and replace any damaged or worn insulation on the electrode holder or cables.

Additionally, using the wrong type of electrode or welding technique can also cause shocks.

Different electrodes and techniques have different requirements and should be used accordingly.

It’s essential to follow the manufacturer’s instructions and guidelines to ensure that you’re using the right equipment and techniques for the job.

Frequently Asked Questions:

Can I touch the rod while welding?

No, it’s not advisable to touch the rod while welding due to potential UV/IR radiation and heat. Make sure you have all the right safety gear and follow protocols before starting.

Can you hold the part you are welding?

It’s not recommended to hold the part while welding without protective gear. It’s best to use tools and clamps instead so you don’t have to risk getting burned or injured.

Conclusion

Let’s be honest; welding is a potentially dangerous activity if you’re not careful. Touching the metal while it’s being welded can result in serious burns and electric shocks.

Nonetheless, by using the correct strategies and resources alongside protective equipment, you can easily steer clear of contact with metal.

Remember, safety should always be a top priority when welding. So, keep your protective gear on, follow the safety protocols, and don’t play the “Hot Potato” game with red-hot metal.

If you want to learn more about welding safety, our site has plenty of resources available to help you stay safe and secure on the job.

Happy Welding!

The short answer is no, you cannot, but you can join them by using other welding techniques.

Brass is an alloy of copper and zinc. The percentage of zinc in each piece, will affect the melting point of the metal, so this will obviously affect a weld.

It also has a lower melting point than copper, so overheating it can cause a porous weld with cracking. If you want to weld brass to steel, the melting points are not the same, so this does cause a problem.

You can use a brazing technique to join them, or solder them

Brazing

Brazing is a method whereby a filler rod is melted in to the joint and this creates the bond.

A brazed joint is not the same as a welded joint, as the base metals are not melted, so they retain their physical properties.

Brazing metals is not a hard process, but it does need practice to get it right. You will be working at lower temperatures as you will not be melting the base metals.

• First you need to heat the base metals until they are hot, but not melting. Ideally the metals should be glowing red.
• Then, apply the filler metal. The heat of the base metals should melt this so that that it melts in to the joint without further heat being applied. If done correctly it should be drawn in to the metals by capillary action, and will flow in to the joint.

Once it has cooled, your joint is complete.

Soldering

You can also solder the two metals together. The best solder to use is silver solder.

• Clean both surfaces thoroughly before you start. Use a wire brush or sandpaper to remove al traces of oxidization.
• Apply liquid flux, and clamp the two pieces together.
• Heat both surfaces.
• You will need to test the heat before you apply the solder.
• When the heat from the metal is enough to melt the solder, you can apply the solder stick. It should flow in to the joint.

As with brazing, practice this first, as overheating the solder or metal may mean you don’t have as strong a joint as you would like.

Safety

Welding always has it’s dangers, but when working with brass, you have to take extra precautions.

• When working with brass, you must remember that molten zinc can produce toxic fumes. Wear a helmet with good ventilation and make sure your work area is properly ventilated.
• Zinc also has a tendency to spatter, so you should wear protective boots and gloves as a minimum.

Can You MIG Weld Brass to Steel?

MIG welding brass to steel directly is not typically recommended due to the significant differences in their properties.

Brass, an alloy of copper and zinc, has a much lower melting point compared to steel, an alloy primarily composed of iron.

If you attempt to weld these two metals together, the brass might begin to melt and even vaporize before the steel gets sufficiently hot to form a weld!

This can make it pretty much impossible to create a bond that’s strong and reliable.

Brass and steel react differently to heat. They expand and contract at different rates when they get hot and then cool down.

This mismatch can introduce stress at the joint where they meet. As the metals cool after welding, this stress can lead to the formation of cracks or even cause the weld to break apart.

These weak spots are not only structurally unsound but can also be potential points of failure when the joined metal is put under any sort of stress or load.

Frequently Asked Questions:

Is a brazed joint as strong as a welded one?

If completed correctly, a brazed joint should be every bit as strong as a welded joint. Just make sure that the zinc is not overheated.

Can you use brazing for other metals?

Yes you can. It’s an easier way to join together two metals which have a big difference in melting points.

Does brazing or soldering produce slag?

This is one of the good things about brazing. It creates a smooth surface which requires very little, or no, finishing. If you use the solder method, you may need to chop some excess solder away, but if you test the temperature as you go, it should flow smoothly in to the joint.

Conclusion

Welding different metals can be a problem, particularly with alloys and with metals which have a difference in their melting points.

Brass must always be welded with caution, due to the potentially toxic nature of the zinc it contains.

Brazing and soldering are two safe and efficient methods which can be used with brass and steel, as well as other metals.

The main problem is making sure you have the correct temperature. You won’t be heating metals as you would with a weld, so it will take some practice to be able to braze or solder properly.

Although the temperature will be lower, please use the same caution as you would when welding, as they can still give a nasty burn.

If you need to break a weld you will need to use a thermal method, either a plasma cutter or an oxy-acetylene torch, or a mechanical method, such as a grinder or circular saw.

The method you use will largely depend on the type of weld you want to break and the metals involved.

Why would you break a weld?

A good weld should last a long time but there are reasons why you may want to break one.

• Sometimes mistakes are made and if a weld hasn’t been completed correctly, it may need to be replaced.
• Over time, welds can be come damaged and need to be repaired. If they can’t be repaired, then they’ll need to be broken and replaced.

There are different methods for breaking a weld. You can use a heat or thermal method, or a mechanical one. Whichever method you choose, cut your weld on either side, rather than try to go straight through it.

Thermal methods

When you created the weld, you used heat to melt the metals. You can also use heat to break it by using an oxy-acetylene torch or a plasma cutter.

• Plasma cutter

Plasma cutters use a jet of hot plasma to cut through metal. Although they only have a small nozzle, they can generate heat up to 20,000 degrees Celsius and will give you a clean, precise cut every time. Once you have your plasma cutter, you don’t need any additional equipment.

While it may be easy to use a plasma cutter when you know what you are doing, you should first take the time to familiarize yourself with the speed, power and angles of attack before you work on a specific project.

Plasma cutters have several advantages when breaking a weld.

• They are 5 x faster than manual torches
• They can cut through thick or thin welds and a wide range of materials
• They are easy to use
• Plasma cutters do not use any flammable gases

Plasma cutters can be expensive, but prices are coming down so they are more affordable.

• Torch cutter

Oxy-acetylene torches combine acetylene with oxygen to create flames of up to 3500 degrees Celsius. These flames can cut through metal, and can also weld them together. This can be more dangerous than using a plasma cutter as you are working with gas at a high temperature. You can also get electric cutters which create the same flame, but do not use gas.

If you use a gas torch, you can either gouge the metal or cut it.

• Gouging: This involves heating the steel to approximately 900 degrees Celsius. This causes it to melt and the weld comes apart. This does take some time to get the hang of and must be done carefully, as too much heat can buckle the metal.
• Cutting: This uses the flame to cut through the metal by heating the metal and then releasing a stream of oxygen which blows through the cut.

Torches are easy to use, once you have mastered the basics.  There are advantages to breaking a weld with a torch.

• They are easy to use and work quickly
• They are cheaper to buy then plasma cutters
• They are portable so can be used anywhere
• They work well with larger welds
• Can also be used to weld metals together

The one thing you need to be aware of is that you will be working with gases and at a high temperature, so always consider your safety and that of others.

• Stick welding

If you have a stick welder, then this can also be used to break a weld. You will need to buy a special nozzle to do this. Set up your welder in the usual way, and heat the metal. Once is it hot enough, the nozzle will release a stream of air which will break the weld.

If you already have a stick welder, this could be an option if you need to keep your costs down.

Mechanical methods

Mechanical methods do not use heat to break the weld. The weld is cut manually with the right equipment and usually involves cutting, grinding or drilling.

• Grinder / circular saw

Angle grinders can also be used to grind down a weld bead or create beveled edges, but they are a good way to break a weld too. Circular saws are also a good method of breaking a weld. They will apply most of the pressure for you, so all you need to do is hold them steady and move them across the metal.

• Grinders and circular saws are a cheap method of breaking a weld.
• They do not use high temperatures

Grinders and saws will do the job, but they are not as precise as a plasma cutter.

• Reciprocating saw / Hacksaw

These look like saws but are powered so they are easier to use. The blades are ideal for smaller surfaces or if you are working with a smaller or thinner weld.

• A good choice if you are on a budget
• Easy to use, even for beginners
• Work very well if breaking a smaller weld

Breaking a Weld

Before you begin make sure you are wearing the right protective gear and make sure the area is prepared. If you are working with a torch or plasma cutter, make sure there is no flammable material anywhere close to where you are working.

Make sure you are wearing safety equipment which can include a visor, eye goggles, gloves and apron.

1. First mark out where you need to make the cut to break the weld. You just need a pencil or marker to do this.
2. Even though pieces are welded together, clamp them in place before you start. As the weld begins to come apart, they will move so it’s vital to make sure they stay exactly where you need them.
3. If you are using a torch, turn on the gas tanks, light the torch and adjust the flow.
4. Depending on your chosen method, move carefully across the line you have drawn, moving away from you. Don’t linger as this can cause too much metal to melt.
5. Allow the metals to cool before you touch them. Even mechanical methods will cause the metals to heat up.

Frequently Asked Questions:

Can you weld over a piece once you’ve broken it apart?

You can, but it’s not always that simple. Some methods of breaking them apart, such as applying high temperatures, can alter the consistency of the metals, so they may not weld back to how they were originally.

Which is the best method?

There is no right or wrong way to break a weld, but you should consider the metal and type of weld you are looking to break. A strong weld will need more powerful equipment to break it effectively.

Can you break a weld with a drill?

If you’re breaking a weld, a drill will be very time consuming, it won’t create a neat cut and it could damage your drill bits. If the weld is rusty or damaged, a drill may work, but using a thermal or other mechanical method would give you a better result.

Conclusion

If you’re breaking a weld, you need to make sure you have practiced first and set everything up correctly, just as you would if you were carrying out a weld.

It can be tempting to ignore safety equipment, but breaking a weld will create a lot of heat and you may find slag is blown around too. For this reason, always consider where you are working and what the dangers may be.

Once the weld is broken, don’t automatically try to weld it again. Check the original metal to make sure it has not deteriorated in anyway, before attempting to re-attach it.

If you are a home DIYer, then you may already have all you need to break a weld, but even if you do not, you will be able to find a method which suits your ability and your budget.

Wire feed welding uses a welder with a continuously fed wire electrode. It is a good choice for thinner metals, and once you’ve set the wire thickness and speed, you can begin your weld.

You will need an understanding of welding but the process is easy and beginners will be able to use it.

What is wire feed welding?

Wire feed welding is also MIG, GMAW welding and flux core welding. It is the process of automatically feeding the wire through the welder.

As the wire feeds through, it forms an arc to produce a shielding gas. The heat produced welds the workpiece and filler metal electrode together.

Wire feed welding is an excellent choice for mild welding.

How to wire feed weld

You will need a welder which has an automatic wire feeder.

• The roll of wire is placed in the welder. There are also two drive rolls and these feed the wire through. As wire is available in different sizes, it’s important to set the drive rolls to match, otherwise the wire will not feed through properly.
• The electrode is then fed in to the electrode holder. This is shaped like a gun. To start the process, you simply pull the trigger, which will start the power supply.
• Once this has started, the arc is created, and this simultaneously heats the base metal and melts the wire electrode.
• The shielding gas is then created.
• The rollers will then feed the wire through in a continuous motion, so you don’t have to keep stopping.
• To complete the weld, simply move the gun along the workpiece.
• Make sure you push the wire and not pull it. This creates a cleaner weld and you won’t have to clear off slag.

Setting up the weld

Before you start, it’s important to set the wire feeder up correctly.

• Angle: The angle of your weld will depend on the metal you are working with and the joint you are creating. There are four angles: flat, horizontal, vertical and overhead.
• Flat: For butt joints, the angle between the gun and the workpiece is 90 degrees. The filler metal is aimed straight in to the joint, but the travel angle can be adjusted from 5 to 15 degrees. You can go back and forth over the weld to create a smooth join. If you’re working on a T-joint, the angle between the wire and the workpiece should be 45 degrees and you can take multiple passes over the weld. For a lap joint, the work angle should be 60-70 degrees. This can be adjusted depending on the thickness of the metal. The thicker the metal, the larger the angle should be.
• Horizontal: If you’re working on a horizontal joint, you will need to consider the effect of gravity. The work angle should be adjusted from 0 to 15 degrees, and the angle will need to be correct to prevent the filler metal from sagging over the edge. You can use a combination of push and pull to create a smooth weld.
• Vertical: It’s very important that you take the time to set this up correctly. The travel angle should be 5-15 degrees from the perpendicular. You will also need to use a weave technique to control the size and shape of the bead.
• Overhead: This is very tricky to do correctly, and only experienced welders should try this.
• Wire: The correct wire is also essential. There are 2 types which are commonly used with wire feed:
  • ER70S-3, which is good for all purpose welding
  • ER70S-6, which is ideal for dirty / rusty steel, and also for repairs or maintenance

• Thickness:

The thickness of the wire will depend on the weld you are creating.

• Length: The length of the wire is also a consideration. This is the amount that sticks out of the end of the gun, usually 3/8 of an inch. If it is longer than this, the arc will produce a sizzling sound which will affect the weld.
• Gas: The shielding gas plays an important role in the overall quality of the weld, so it’s vital to get it right. Not only that but if the wrong gas is used, it can create potentially harmful fumes. The best shielding gas for carbon steels is a mix of 75% argon and 25% carbon dioxide. You can use 100% carbon dioxide, but that does create more spatter and rougher beads.

If you’re not experienced with wire feed welding, always practice first.

Advantages

• Wire feed welding works well with thinner metals, including aluminum
• There is no need to stop to replace the electrode
• It creates less slag and a cleaner weld due to pushing
• It is easy to learn, though you will need basic welding skills

Disadvantages

• Wire feed welding creates a lot of heat, so it is not always suitable for overhead and vertical welding.

Frequently Asked Questions

Is MIG the same as wire feed?

Wire feed welding includes MIG welding, as this uses an automatic wire feeder.

Do you need gas to wire feed weld?

You don’t always need gas. If you use a flux core, this will create its own shielding gas. However, if you are using a MIG welder, then you will need gas to operate it.

Does wire feed welding create slag?

One of the nice advantages of wire feed welding is that it doesn’t produce slag. If done correctly, you should have a nice, clean weld.

Conclusion

While wire feed welding is easy to pick up, you will need to practice when you start. Making sure the settings are correct and that you are working at the right angle is very important, so if you’re new to welding, practice is essential.

Keeping one hand free to control the gun makes it quicker for you to complete the weld and help you create a cleaner weld too. You do not need to stop mid weld to change the wire, as most rolls are a few meters in length.

If you’re working with thinner metals, then this is the best method to use, whether you’re a professional or a DIYer looking to complete some home projects.

MIG vs Arc Welding, what’s the difference? Arc welding creates an electric arc to melt two metals and join them together. MIG welding uses an automatic wire feed which melts an electrode and adds a filler metal to weld two pieces together.

Both methods work very well and both create an arc to shield the weld. The difference is in how the arc is made, and so how the weld is formed.

MIG Welding

For MIG welding you need a MIG welder. The cost of these will vary, but there will be one for all budgets. MIG welding stands for Metal Inert Gas, and it uses gas as part of the process. Some MIG welders still require a separate gas bottle, but more modern machines incorporate the gas in to the welder.

MIG welders use a gun which feeds wire through automatically. The wire, or electrode, melts and joins with the base metals. For MIG welders which don’t have a separate gas tank, you will need wire which is covered in flux. As this flux melts, it creates an arc which protects your weld.

Setting up a MIG welder is relatively easy, but will take practice. MIG welders allow you to set:

• The speed of the wire.
• The thickness of the wire.
• The voltage.

The wire is placed in a spool inside the machine, then fed through the electrode holder. This is shaped like a gun and has a trigger to begin the feeding process. As the wire feeds through, it creates an arc. The electrode and metal are both heated to create a weld pool, while the gas shields the weld pool from external gases.

MIG welders work well on both thick and thin metals as the power can be adjusted.

Advantages

• MIG welders are easy to use.
• They require minimal setting up so are good for beginners.
• Can create horizontal, vertical and flat welds.
• There is minimal slag and spatter.
• Controlling the weld is easy, as settings can be altered depending on the metal being welded.
• Automatic wire feed means you don’t have to keep stopping to replace the electrode. The trigger also has the option to stop / start as you need to.
• Can weld a variety of metals, including carbon steel, stainless steel, aluminum, magnesium, copper, nickel and alloys.

Disadvantages

• Although MIG welding can handle a variety of metals, it works best with thin to medium thick metals.
• MIG welders can be less portable, due to the need to carry a separate supply of gas.
• They are also not a good choice if working outside, as the weld can be affected by wind or rain.
• The materials being welded do need to be thoroughly cleaned first.

Arc Welding

There are several methods of arc welding, but not all arc welders work the same way. Arc welding machines have an electrode holder but these do not always have a trigger and they do not all have automatic line feed.

Arc welding creates an arc using a power supply. This produces heat of up to 6500 degrees Fahrenheit, and this melts the 2 metals to be joined. The electrode in an arc welder is used to carry or conduct the current. It melts in to the weld pool together with the two metals to create the join.

The arc acts in the same was as a shielding gas, in that it protects the weld from atmospheric gases. Molten metals can react with nitrogen or oxygen, so protecting them will create a better weld.

Arc Welding: 8 Main Methods

Most welding methods will create an arc in some way, and these include:

• MIG / MAG (Metal Active Gas) welding
• SMAW (Shielded Metal Arc Welding
• FCAW (Flux Cored Arc Welding)
• SAW (Submerged Arc Welding)
• ESW (Electro-Slag Welding)
• SW (Arc Stud Welding)
• TIG (Tungsten Inert Gas Welding)
• PAW (Plasma Arc Welding)

Advantages

• Arc welders are cheaper to purchase and use.
• Can be used with thicker and heavier materials.
• Easier to transport, as there is no gas to carry
• The metals do not have to be cleaned before welding
• Arc welding can be done outside, as it is less prone to the effects of the weather.
• As it creates a lot of heat, it works very well with base metals with a high melting point, such as heavy steel construction
• Creates less smoke and sparks
• It doesn’t use a separate gas supply to create the shield
• You don’t need a consumable electrode.

Disadvantages

• Not a good choice for beginners
• Produces a lot of waste
• Arc welding is not good for thinner materials and cannot be used on aluminum or titanium
• It does leave slag so there will be some cleaning required after the weld.

Frequently Asked Questions:

What type of gas is used in a MIG welder?

MIG welders use argon, carbon dioxide or a mix of the two. The gas and percentage will depend on what it is you are trying to weld.

Is MIG or Arc stronger?

If used correctly, they will both produce a strong weld. Arc welding is used on larger projects such as building and ship building, while MIG is better for thinner metals.

I work on different sites. Which is the best to use?

If you want something you can carry easily, then Arc welding is more portable. It also works outside in all weathers, where MIG welding cannot be used in adverse weather conditions.

Conclusion

While MIG welding does create an arc, it is not the same as Arc welding and is better for those new to welding. The need for additional gas in MIG welders can be very off putting, but many welders have now been adapted so you no longer need additional gas.

Arc welding will require some welding experience and is often used in large jobs, and is excellent for larger joins and heavier metals. It does create a lot of heat though, so extra care should always be taken.

As with all welding, the best method is the one you feel comfortable using and the one which will create the right join for your project.

MMA welding uses a high intensity electric arc to weld the workpiece to the electrode. It is also called stick-electrode, arc welding or SMAW.

The MMA process

If you are completing a weld using an MMA welder, the electrode must be fed through manually. This is the filler metal and will conduct the current.

The electrode will have a flux coating which is designed to melt as it heats up. The electrode will create molten metal while the flux will create an arc to form a shielding gas. This arc shields the electrode and the workpiece so that they form a weld pool. The mounted flux will create slag on the weld which will need to be cleaned when it is completed.

As with all welds, you must ensure that everything is set up correctly. For MMA welding there are several things you must prepare before you begin.

• While MMA can be very forgiving, you will still need to prepare your workpiece properly. Always wipe it down so that it is free from dust or grease and remove as much rust as possible.
• Make sure you have chosen the correct travel speed for the electrode.
• You will also need to have the correct size of electrode. Most welding jobs will handle electrodes of 2.4 mm, 3.2 mm and 4 mm. If you are welding a smaller job, you will obviously need a smaller diameter such as 1.6 mm or 2 mm.
• The angle of the electrode must also be correct and this will also depend on the type of weld you are completing. As a rough guide, if you are doing stick welding or MMA welding you should hold the gun at an angle of 20° to 30°, but if you’re carrying out a fillet or tee weld, you should hold the wire and an angle of 45°.
• With MMA welding the length of the arc should usually be equivalent to 0.5-1.00 times the diameter of the electrode.
• MMA welding will need a high current of between 50 and 350 Amps, with a low voltage of 10-50.

Electrodes

It’s also important to select the right electrode. The most commonly used are cellulosic, rutile and basic.

• Basic: This mainly consists of calcium compounds, and will create a shielding gas of carbon dioxide.
• Rutile: The constituent of this one is titania, and it creates a carbon dioxide shielding gas.
• Cellulosic: The main constituent in this electrode is Cellulose, and it creates a shielding gas which is a mix of hydrogen and carbon dioxide.

Uses of MMA welding

As with all welding methods, MMA welding can be used on most joints. It handles cast iron, stainless steel, steels and non-ferrous items very well and is ideal for moderate and high resistance carbon steels.

Advantages

• MMA welding is relatively inexpensive and has low maintenance costs
• Heavier metals can be welded with the same output, as they can generate more power.
• Many MMA welders are compact, so they are portable. This makes them ideal for site and field work, and as they do not need a shielding gas, they are not usually affected by weather.
• They handle rusty or dirty materials very well.
• MMA welding is easy to learn and easy to use.
• Works with most metals, including iron, steel, copper alloys, nickel and aluminum

Disadvantages

• Working with thinner materials can be tricky as it is hard to avoid ‘blow through’
• The process can be slower than others, as the electrodes do need to be replaced.
• Slag is produced with the weld, and this will need to be chipped off.

Frequently Asked Questions:

What do you need for MMA welding?

• A reliable power supply which has both AC and DC. While all AC electrodes can be used with DC, not all DC electrodes can be used with AC.
• You will need a ground cable and a welding cable, which should have an electrode holder. Make sure this will hold the electrode securely.
• As with all welding, there is a risk of being burned by spatter so always wear a face shield and gloves. Leather or safety gloves are recommended, as spatter can burn through cheaper ones. Aprons can also help protect your body from burns. When removing spatter, wear your face shield or goggles to protect your eyes.
• Always consider ventilation when welding. If working outside, then the fumes will likely disappear on their own, but indoors make sure there is good ventilation and that the fumes are blowing away from you where possible.
• You will also need a wire brush and chipping hammer to clean the joint before welding and remove the slag.

Which metals are the electrodes available in?

MMA electrodes are available in a variety of metals to make sure you create a strong joint.

You will be able to get electrodes in

• Cast iron
• High carbon steel
• Mild steel
• Non-ferrous
• Special alloys.

Can I use my MMA welder outside?

One of the big advantages of MMA welding, is that is can be used outdoors. As you don’t need to create a shielding gas, MMA welders are less susceptible to the weather so they can be used almost anywhere.

Is MMA suitable for beginners?

Beginners will be able to learn MMA welding, but it’s not the easiest process if you’ve not welded before. Other forms of welding, such as MIG welding, have an automatic electrode feeder which is easier for beginners.

Conclusion

MMA welding is ideal if you work outside or on site. Most MMA welders are portable, and as the process creates its own arc, it is easier to work in all weather conditions.

Manually feeding the electrode isn’t easy, and it will take practice to get the right speed and calculate the correct settings. For this reason, it’s not a good choice for beginners, but that doesn’t mean you should avoid MMA if you’re new to welding. Just take the time to practice everything before you get started.

Due to the amount of slag created, it can be time consuming, but as it is a very forgiving process, it does make it easier to work with all metals.

There are different types of welding and using the right process will make a big difference to your project. The wrong weld can mean having to start over.

Two popular methods are Stick and MIG welding. Both are excellent at creating good welds, but there are some differences. Stick welding can be better in some circumstances than MIG welding and vice versa.

Let’s take a look at how each method works.

MIG Welding

MIG welding, Metal Inert Gas welding, is relatively easy to learn, but as with all welding, it does take practice.

MIG welders feed a wire spool electrode through the welder, which makes it easier to select the right length of wire. The welder has a trigger which releases the spool and this feeds the wire through the gun. Most welders will have the option to adjust the speed, polarity and voltage.

Unlike other welders, MIG welders use a combination of gas and electricity to melt the electrode. The gas, a mix or Argon and Carbon Dioxide, is used to protect the weld from nitrogen and oxygen. Older MIG welders have a separate tank for gas, but some newer models no longer require this, making them a better option for everyone.

One major benefit of using the spool to feed the wire, is that you get a clean weld with little splatter. You do need to clean the metal first as any pain or oil can affect the quality of the weld.

Unfortunately, as you need to shield the gas to create a weld, MIG welders are not as reliable if used outdoors. If the gas blows away, your weld won’t work. If used indoors they also don’t create many fumes or splatter, so they are a good option for indoor welds.

MIG welders work well with most metals, particularly thinner ones such as carbon steel, stainless steel, copper, aluminum and magnesium.

There are many benefits to using MIG welding, and of course some drawbacks.

Advantages:

• As the spool provides a continuous feed of wire, you don’t have to keep stopping to alter the cable. This makes it quicker to create a number of welds.
• MIG welders create a good weld on metals as thin as 24 gauge.
• Welds are clean with no slag or splatter. This not only looks good, but saves you time cleaning the weld after.
• The lack of splatter also makes it safer to use. While the heat is still a safety issue, you don’t have to worry about being burnt by splatter.
• Less electrode is wasted, as the spool will only feed through what you need.
• Suitable for beginners.

Disadvantages:

• MIG welding can be more expensive as it requires gas to work as well as electricity.
• Although many MIG welders are portable, they can still be quite cumbersome as they require a source of gas too.
• They do work on all metals, but if you’re working with a thicker metal, you won’t get such a good join.
• Before you start work, you must clean the surface so it is free from rust, paint or dust.

Stick welding

As with MIG welding, stick welding allows you to work with different metals, but it works better with thicker metals. It is also referred to as Shielded Metal Arc Welding (SMAW) and is a popular method used by home-shop welders and electricians.

Stick welding uses a metal rod which is coated with an electrode. The stick is heated and when it comes in contact with the metal, the 2 pieces melt and weld together. It can be used on alloys and ferrous metals, such as nickel, copper, aluminum, iron and steel.

It is great for working outside as it is not affected by wind or rain, and being outside helps to disperse smoke and fumes caused by the weld. It is also an economic welding method, and you don’t need to clean rust or dirt off the surface first.

It does, however create a lot of slag and splatter, so any welds will not be clean and you will need to spend some time cleaning them up. Due to the splatter, more care should be taken to protect yourself from burns while you are welding.

Interesting fact: The first  patent for stick welding was issued in the late 1880s

Let’s take a look at the advantages and disadvantages of Stick welding.

Advantages:

• Stick welding can be used both indoors and outdoors, so it works well on farms, automotive repairs and outdoor projects
• There is no need to clean the metal before welding
• It is easy to change rods
• Suitable for beginners

Disadvantages:

• There will be splatter and this causes a hazard, both to the body and to any flammable material around you.
• Slag and splatter mean the weld won’t be clean and you’ll spend some time cleaning afterwards
• Doesn’t work well with metals less than 1/8 of an inch in thickness
• Can take longer to weld due to the need to clean the weld and swap as need to clean after, swap electrodes

Stick Welding v MIG Welding

So now we’ve looked at the two different types of welding, which one is the best? There is no right or wrong answer and it very much depends on what you are welding and where. So, here’s a quick comparison for you.

• Easy to use: If you’re new to welding or simply want something easy, then MIG welding is the better option. It is quick to weld and welds cleanly as well. Stick welding is easier to set up, but because it creates more splatter, there can be more work needed to clean up the weld.
• Cost: This is a consideration for most of us. As well as the cost of the machine, there is also the question of how much it costs to operate. Stick welders are cheaper to operate as MIG welders rely on an additional gas source.
• Portability: If you need to work on different sites, then stick welders are more portable. Many MIG welders, however, are now being manufactured which can be easily transported.
• Quality of weld: This is obviously important for all welds, but is one better than the other? MIG welders will create a cleaner weld, but you do need to make sure that the surface has been cleaned so there is no corrosion or paint. Stick welding is messier, and you will need to clean up the splatter it causes. You won’t need to clean the surface as thoroughly before you weld.
• Indoor / Outdoor: If you’re welding outside, stick welding is the best option. Not only is it resistant to wind and rain, but the outdoor environment helps to disperse the fumes it creates. MIG welding can be adversely affected by weather conditions and the gas does need to be shielded, so is better used indoors.
• Metals: Both types of welding will work with most metals, but the thickness of the metal will make a difference. If you’re working with thinner metals, such as copper, brass, stainless steel or aluminum, then a MIG welder will perform better. Stick welding doesn’t work as well on thinner metals, but it is better for thicker ones.
• Intended use: This is one where you need to take on board the conditions you will be working in. MIG welding is a quick and clean way to repair outside projects, such as fences, metal sculpts, and garage and garden projects. However, it is not always the best to use outside. If conditions are poor, then you will need to use stick welding. This is also best for larger projects such as lawnmowers, utility trailers and automotive repairs.
• Additional resources: This not only puts the cost of the weld up, but can also make it more inconvenient to work. MIG welding needs gas, and this is something you will need to consider. Stick welding requires no gas and just relies on the arc vaporizing the flux covering.
• Safety: All welding comes with hazards, so whatever method you use, always have your own safety in mind, as well as the safety of others around. Stick welding creates a lot of splatter, so you will need to cover your forearms and body as well as your face and hands. MIG welding does not create splatter, but it does get hot and you will need to check your gas to make sure it is pumping correctly.

Frequently Asked Questions:

I travel around for work. Which is the best welder to carry?

MIG welders are designed to be portable but they can still be bulky and the need to carry gas can make them hard to transport. Stick welders are easier to take from site to site and will work better if you work outside.

What happens if I don’t clean the metal first?

If you’re using a MIG welder, then any dust or oil can prevent the weld from being strong. If you’re using a stick, then the dirt won’t matter as it will stick anyway

What safety equipment do I need.

As a minimum you need to protect your hands and head from any heat. If you’re using a MIG welder, a helmet and gloves should be enough. If you’re using a stick welder, be prepared for extra splatter. This can cause some nasty burns so protect your arms and upper body too. Stick welders also create more smoke and fumes, so take this on board before you start work.

Conclusion

As you can see, the comparison between stick and MIG welding really does depend on what you are working on. Both work very well and will give you a strong, reliable weld as long as you use them properly.

Both methods are good for most welds, but as a general rule if you’re working with thinner materials, use a MIG welder and thicker metals need a stick welder. You can use a MIG welder outside, but if the weather is not very good, you won’t get a good weld.

For both methods, it can be trial and error to see which works best for you. MIG and stick welding are good choices for beginners as they are both easy to operate and they are not expensive to buy. Running costs may be slightly higher for MIG welding, but that can be compensated for by the fact that stick welders need more time to clean up the weld.

Professional welders with use both methods and as you practice more and get more experience, you’ll soon get used to  the pros and cons of both systems.

Rebar is invaluable for building projects and being able to join two pieces can add to the overall stability of the construction. Welding the rebar is a great way to achieve this, but can you do it? The short answer is yes, you can, but not all rebar will react the same way.

What is Rebar?

Rebar, or reinforcing bar, is a steel bar which adds tensile strength to concrete. It fortifies the concrete to make it more compacted and stronger.

There are different types of rebar, and while they are all suitable for many construction jobs, some are better than others for larger constructions.

Types of Rebar

Mild Steel bar

This is possibly the most widely used. It has good tensile strength, it is easy to work with and it is cheap.

• Texture: The surface is plain and round in shape.
• Width: Available from 6mm to 50mm
• Uses: Mild steel bar is mainly used where steel bars are needed to slide in to a metal sleeve. This includes dowels at expansion joints, contraction joints in roads and in column spirals.
• Properties: It is easy to cut and will bend without being damaged.

Deformed steel bar

There are different types of deformed steel bars, and they are both designed to reduce slippage. They’re also the best when it comes to welding.

• Texture: The surface has ribs, lugs and indentations.
• Width: Available from 6mm to 50mm
• Properties: Better strength than mild steel bars.

TMT Bars (Thermo-Mechanically Treated Bars)

These have been heat treated, which adds extra strength to the concrete. TMT bars are easy to bend, flexible and a good choice for welding.

They are used for RCC work and have excellent qualities:

• Superior strength
• Welding ability
• Excellent bending ability
• Good ductility
• Resistant to corrosion
• Will withstand earthquakes

HSD bars (High Strength Deformed Bars)

These are cold twisted steel bars. They have a low carbon value and are used for reinforcing residential and commercial constructions and bridges.

Just like TMT bars, the have their own excellent properties:

• Superior bonding strength
• High tensile strength
• Better welding capacity

You may also come across other types of rebar but these are not so widely used.

• European Rebar. This is made of manganese so it does bend, but it is not suitable for places with extreme weather conditions.
• Carbon steel rebar. This is also known as black rebar. While it has good tensile strength, it is prone to corrosion.
• Epoxy coated rebar. This is carbon steel rebar which has an epoxy coat. While this does reduce the corrosion, the coating is still delicate.
• Glass fiber reinforced polymer. This is an alternative to steel. Made from fiber glass, it does have good tensile strength.
• Galvanized rebar. This is coated with zinc, so it resists corrosion. It is also an expensive option.
• Stainless steel rebar. This is resistant to corrosion, harder to damage and can be bent. It is also the most expensive option.

Why do you need to weld rebar?

Rebar adds strength to concrete, but there are advantages to welding it. Welding the bars can provide more rigidity to a structure. If you’re creating a rebar mat or cage and transporting it to site, welding will also make this stronger so it is less likely to come apart.

As with all projects, before you start, always make sure you have exactly what you need and that you have the appropriate materials.

• First, make sure you have the right kind of rebar.
• Some rebar will need to be reheated, so check whether or not you need to do this before you start.
• Check your filler. Do you need welding wire or rod?

How to tell if rebar can be welded

Obviously, the main criteria for welding rebar is the metal content. You may need to refer to Structural Welding Code AWS D1.4, but if you use a low-alloy steel rebar, then it is weldable and you don’t have to worry about any special considerations.

Rebar with a high carbon content is not suitable for welding.  You need a carbon content of less than 2.1%.

There are some easy ways to see whether your rebar is weldable or not.

• If rebar is of welding quality it will be grade-W and will be marked with a W. If the rebar does not have a W on it, then it is not suitable for welding
• Another way is to look at the end of your rebar. If both ends are the same color then it cannot be welded. If one end is red and the other is a different color, then it is suitable for welding.

You should also look at the joint you are looking to weld.

• You can weld lap joints, butt joints and splices.
• Parallel bars must be parallel and perpendicular.

Which filler to use

As with all welding jobs, it’s vital to choose the right filler and this depends on the welding method you are using. IF you’re using A615 Grade 60, the table below shows what should be used.

A full table of which filler should be used with different grades of rebar is available from the American Welding Society.

Preheating

Some rebar will need to be preheated to make sure you get a good bond. The main things you need to consider are the size of the rebar and the carbon content.

Rebar with a low carbon content will require more reheating so you will need to check the certificate if you can.

Welding rebar

Once you have your rebar and you’re ready to begin, prepare everything you need first.

You will also need to ensure that your rebar doesn’t move or you could end up with it out of line. A good way to hold it in place is a jig. If you are welding two bars next to one another, make sure they are exactly parallel before you start.

If you’re welding a joint, make sure the rebar is angled correctly before you start.

It’s always best to test your weld first rather than make a costly mistake.

Frequently Asked Questions:

What happens if I weld the wrong rebar?

If you use the wrong rebar, this will affect the tensile strength of the concrete and cause it to crack. Always check you have the exact rebar in the specifications.

My rebar bent while I was welding it. Is it ok?

You will need to check with the engineer. They calculate tolerances very precisely and any bend could affect the overall strength.

How do I know which filler to use?

The AWS has information to help you make the right choice of filler. They have a table which outlines which filler is required for different grades of rebar, and the best fillers to use. Try to keep to their guidelines when you’re welding rebar to ensure you get the best tensile strength.

Which type of welding do I use to need to weld rebar?

AWS guidelines say you can use three types of welding on rebar

• Shielded Metal Arc Welding (arc or stick welding)
• Gas Metal Arc Welding (MIG or wire feed)
• Flux Core Arc Welding

Conclusion

Welding rebar can be daunting when you first start. Any mistake could be costly, or could jeopardize the strength of a structure. If in any doubt, the AWS do publish guidelines to help you choose the right type of rebar and the method to use. The engineer on your project is also a good person to connect with if you have any questions.

There are several welding processes available, with different advantages and applications, and some are better than others. But one thing all these welding processes have in common is the use of gases.

Welding gases play crucial roles in welding processes, such as shielding the weld pool from contaminants in the air and heating the filler electrode and parent metal. Welding gases include inert and active gases alike, and the most commonly used ones are Argon, Carbon dioxide, Helium, and Oxygen.

This article discusses welding gases in greater detail, covering the purpose of gases in welding and the different gases used. It also gives the prices of the most widely used gases and discusses gas safety precautions as well.

What’s The Purpose of Welding Gas?

The primary purpose of welding gas is to prevent contaminants like oxygen, water vapor, and dust in the air from getting into the weld pool. The gas is also used to clean the weld and for heating metals.

Welding gases can be either inert or reactive. Inert gases are inactive; they don’t change or cause any change to the weld, remaining the same throughout the welding process. These gases mainly shield the weld pool, allowing the weld to form without any defects.

On the other hand, reactive gases are active, reacting to different circumstances like temperature and metal type. These gases cause changes to the weld and themselves and enhance the way the weld is formed.

Shielding Gas

The primary purpose of welding gas is to shield the weld pool from elements in the air. In this role, the gas is called a shielding gas, keeping away impurities that can negatively affect the finished weld’s appearance and quality. For instance, oxygen in the air can oxidize the weld pool’s molten metal, reducing its corrosion resistance properties and causing a blackened weld bead.

Similarly, porosity, which significantly reduces the weld’s strength, happens when oxygen, nitrogen, and hydrogen in the air get into the weld pool.

As such, it’s nearly impossible to do MIG or TIG welding without shielding gases unless the filler metal used is flux-cored, which produces a slag that functions like shield gases.

Shielding gases can be inert, which allows them to remain stable, despite the extreme heat produced during the welding process. They can also be active, reacting with the metal and electric arc to affect weld speed, filler metal transfer, arc stabilization, weld penetration, and weld geometry.

Inert shielding gases are used for TIG welding, while active gases are used for MIG/MAG welding.

Purging Gas

Purging gases help to remove impurities from the joint to be welded. Water vapor, oxygen, and other gases can react negatively with the hot metal as it’s being welded, resulting in a distorted and weaker weld.

In most cases, the purging gas is the same as the shielding gas. But while shielding gases act from above the weld, purging gases are applied from below, cleaning the joint as the weld progresses.

Heating Gas

Instead of an electric arc, some welding processes use gas-fueled flames to heat the metal and filler rod to make the weld rather than an electric arc.

What Type of Gas is Used in Welding?

There are a limited number of gases used in welding processes, and these include:

Argon (Ar)

Argon is an inert gas and one of the most abundant gases on Earth. The gas is used majorly as a shielding gas to keep out air from the weld pool and electric arc. It can also serve as a purging gas.

Hundred percent argon is used as shielding gas when MIG welding non-ferrous metals like aluminum, titanium, and copper. But with ferrous metals, you’ll need to add another gas like C02.

When used as a shielding gas, argon produces a thin penetration profile beneficial for fillet and butt welds.

Carbon Dioxide (CO2)

C02 is what we breathe out, and plants breathe in. Additionally, The gas is also released from decomposing organic matter. As a result, carbon dioxide is one of the most abundant gases on Earth and the least expensive shielding gas.

Carbon dioxide is a reactive gas and the only one that can be used in its pure form without mixing with an inert gas. As a shielding gas, C02 produces deep weld penetrations, making it ideal for welding thick metals. However, it creates a lot of spatter, which is one reason it’s commonly used with other gases to reduce the amount of spatter.

Hydrogen (H)

Hydrogen is the simplest gas, and it’s abundant on Earth. It’s also relatively simple to produce and burns without emission, with water as the byproduct.

The gas is only used in small quantities with other shielding gases because hydrogen is highly reactive to other elements. When used in small amounts with other gases, hydrogen produces increased heat in the weld, enhancing penetration and creating a much cleaner weld.

Helium (He)

Helium is the second most abundant gas in the universe, but it’s in short supply on the Earth and is difficult to produce. As a result, helium is one of the more expensive welding gases.

Like argon, helium is chemically inert and used as shielding gas for non-ferrous metals and stainless steel. It produces a wide and deep penetration profile, making it suitable for use when welding thicker materials.

Helium also produces a hotter arc, allowing for faster metal transfer and higher deposition rates. The gas is commonly used with Argon and Oxygen in varying proportions.

Oxygen (O2)

Oxygen is a colorless, odorless, and tasteless gas, but also very reactive.

It’s mixed in small quantities (not more than nine percent) with other shielding gases, as too much of it will cause brittleness. Oxygen adds fluidity to the weld pool and increases the welding speed.

The gas causes oxidation and so should not be used with aluminum, copper titanium, and magnesium.

Nitrogen (N)

Nitrogen is the most abundant gas in our atmosphere, making up about 80 percent of the air we breathe.

It can be used alone as a shielding gas in laser welding and plasma cutting, increasing weld penetration arc stability.

Shielding gas blends containing nitrogen can increase the mechanical properties of metals that contain nitrogen. Nitrogen also serves as a blanketing gas for tanks and similarly enclosed spaces.

Acetylene

Acetylene is a highly flammable gas. In gas welding, It is used with oxygen to make a hot enough flame to melt most metals and filler rods.

Mixed Gases

No gas is perfect for all applications and situations, as they each have their shortcomings. Mixed gases create a balance by combining two gases so that one makes up for the other’s lapses and vice-versa.

For instance, consider two different gases, A and B, where A produces deeper penetration and much spatter, while gas B produces no spatter but a shallow penetration profile. By combining the two gases, you get the best of both worlds – a gas blend that’s better than either of its components, producing less spatter and good penetration.

Mixed gas blends aren’t limited to just two gases and can also be made from Three gases. Some gas mixtures used in welding include:

Argon and Carbon Dioxide

Shielding gas mixtures of 75 to 95 percent argon and 5 to 25 percent CO2 produce a smooth weld with minor spatter. The amount of C02 in the mix depends on the thickness of the steel to be welded. In other words, the thinner the steel, the lesser the amount of C02.

Unlike pure CO2, this mixture allows using the more efficient spray mode of metal transfer, resulting in higher deposition rates and productivity.

Argon, Carbon Dioxide and Oxygen

This shielding gas mixture is much like the Argon and CO2 mixture, producing smooth welds and minimal spatter. But with not more than five percent oxygen added to make the weld pool fluid and increase travel speed during the welding process.

Helium and Argon

A Helium and Argon gas mix is best for non-ferrous metals. Gas blends with 75 percent or more helium are ideal for aluminum and other alloys. You can also use a similar mixture with argon making up 75 percent or more.

Adjusting the proportions of either gas will change the penetration, shape of the weld, and travel speed. Use a mix with more helium when welding thicker metals. On the other hand, use more argon for thinner metals requiring narrow penetration.

Argon, Helium and Carbon Dioxide

There’s a wide range of mix ratios available for this combination, some with more argon and others with more helium. By varying the percentages, you can use this mixture for carbon steel, stainless steel, and aluminum.

Argon and Oxygen

Oxygen can be added to argon in amounts not more than five percent. The added oxygen significantly stabilizes the welding arc while increasing weld fluidity and filler metal droplet rate. It also influences the shape of the bead.

One percent oxygen added to argon is used for welding stainless steel using the spray mode of metal transfer. Increasing oxygen to two percent allows spray transfer mode on carbon steel and low alloy steels.

One percent and two percent oxygen additions yield similar results, but the weld bead will be darker and more oxidized with two percent oxygen added.

Finally, five percent oxygen mixed with argon is the most commonly used argon/oxygen gas blend for MIG welding carbon steel. The increased oxygen in the mix permits greater weld fluidity and higher travel speeds.

How Much is a Bottle of Welding Gas

The price of welding gas depends on two main factors: the size of the cylinder and the type of gas. Gas cylinders are available commercially in three sizes; 40, 80, and 125 Cubic feet (Cu/ft). There are larger cylinders than these three, but they’re only available on special orders or leased out for large-scale projects.

CO2 is the most inexpensive gas you can get. Gas blends with 75 percent argon and 25 percent CO2 are more expensive than pure CO2 and generally cost the same as 100% argon.

The table below shows price ranges for different gasses and cylinder sizes.

Note that CO2 is sold in pounds rather than cubic feet, and 1 lb = 8.741 Cu/ft. So 40, 80, and 125 Cu/ft are approximately 5, 10, and 15 lbs, respectively. Prices for these amounts of CO2 are given below:

• 5 lb = $70
• 10 lb = $80
• 15 lb = $90

These prices include the cost of the gas as well as the cylinder. Refill prices are, of course, much lower.

How Much Welding Gas do You Need?

The amount of shielding gas you’ll need for a project depends on the amount of time it will take to make the weld and the flow rate of the gas per hour. Mathematically this is given as:

Gas needed = welding time X flow rate.

Welding time is given in hours, while the flow rate is in cubic feet per hour (CFH)

For instance, if you’ll use a flow rate of 20 CFH for four hours of welding, the volume of gas needed will be 80 Cu/ft (20 X 4).

It means you will need two 40 Cu/ft tanks or one 80 Cu/ft tank of shielding gas to complete the Job.

Where To Get Welding Gas

You can buy welding gas from places like TractorSupply and Airgas. These two are some of the biggest retailers and will usually have a store nearby.

However, If by chance none of them are available in your area, you can ask around at welding workshops, as they’ll likely know the best way to get the gas.

Still, another way to go is to check online on sites like Amazon and eBay.

Gas Safety

All welding gases have the potential to be dangerous, depending on their characteristics. Handle flammable gases like hydrogen and especially acetylene with great care.

Moreover, always keep flammable gases away from the welding area unless when using them. And when you use them, be sure to have a class B fire extinguisher ready at hand.

With inert gases, there is no risk of a fire as they rarely react with other elements. However, there’s a risk of oxygen deprivation and unconsciousness if you weld in an enclosed area for too long. So when working in such conditions, make sure you take regular breaks and use gas detectors and extractor fans.

Finally, take care when moving gas cylinders around. Although they’re durable and can withstand some hits and falls, you shouldn’t place them in positions where they’re likely to drop or be hit by other objects, as the valve is a weak spot that can break off easily. A broken valve can be as dangerous as a bullet, as it will go off with the force of the gas trapped in the tank.

Frequently Asked Questions:

What Is the Best Gas for Welding Steel?

You can weld steel using both TIG and MIG welders. Argon is the best gas for Tig welding steel, as it’s cheaper and produces minimal spatter and better heat transfer.

When MIG welding steel, the best gas to use is a mix of 75% argon and 25% carbon dioxide (also called C25), this gas blend produces minimal spatter, good penetration, and weld geometry and won’t burn through thin Metals.

Can You TIG Weld With Mig Gas?

You can’t do TIG welding with MIG gases, as these gases are either active or semi-inert like CO2. TIG welding with any gas that’s not entirely inert like Argon and Helium will ruin your blow torch by oxidizing the tungsten inside.

Can You Mig Weld With Tig Gas?

The MIG welding process, despite its name, doesn’t use inert gases but Active gases or a combination of inert and active gases. The active gases like oxygen and C02 make the arc hotter and produce deeper penetration. If you use a TIG gas, you will end up with very little penetration.

Pure argon is the only inert (and TIG) gas that can be used for MIG welding. And even then, only use argon for MIG weld non-ferrous metals like aluminum, titanium, or copper.

Summary

Welding gases are used primarily to shield the weld pool from oxygen, water vapor, and dust in the air, which can deform and weaken the weld. The gases can also be used as purging gases to clean the joint to be welded and as fuel for scorching flames that can melt metal.

The most common gases used for welding include argon, CO2, oxygen, and helium. These gases are either inert like argon, nitrogen, and helium or active like oxygen, acetylene, and CO2.

When using active gases, ensure that there is a fire extinguisher nearby in case of a fire. There is the risk of unconsciousness with inert gases after long periods in enclosed spaces, so take regular breaks and use gas detectors and extractor fans.

Finally, take care when hauling gas tanks. The valve is a weak point, easily broken, and has the potential to become a dangerous projectile.