A Comprehensive Guide to Welding
When it comes to learning how to weld, it’s important to ensure that your equipment, technique, and most importantly your safety precautions, are up to scratch. You’ll need to know a few basics on what to choose, how to prepare your welding area, and how to protect yourself from some of the obvious hazards that come from heat fusion and work with molten materials.
This guide will help you choose the type of welder that’s right for you, give you a rundown of the precise equipment (as well as the types, reasons for, and compliance law behind them), a majority of common safety hazards, as well as helping you to set up your area for welding.
The basics of welding
The invention of modern welding techniques is one of the largest technological achievements of the 20th century. While we think of joining together pieces of metal and constructing large apparatus in terms of minutes, prior to this, it would require a seasoned blacksmith, an entire heated forge and anvil, and painstaking work - coating the join in flux, superheating the metal in the forge over a period of time, and manually hammering the joint together.
The basic concept behind welding is uncomplicated; for the most part it’s simply taking two pieces of material and some filler that has similar melting points, applying intense heat to them, and then using that heat to fuse them together.
Some modern types of welders don’t go by this process, but for the most part fusion welding is still used and only large-scale commercial enterprises utilise other methods.
Types of welders
The basic assortment of welders that a hobbyist or professional is likely to use mostly fall under the following categories:
Gas metal arc welders
Commonly referred to as either GMAW (or ‘Mig welders’ conversationally), these are by far the easiest to learn and operate, the safest to use, and will be what most home users will buy.
‘Arc’ welders operate through creating an electrical circuit between the metal and welder. When you fire it up, a number of things happen: first, the welder emits a type of gas to shield the current from any outside sources, while simultaneously firing an electrical current through the contact point (a spool of consumable wire), which it also automatically doles out instead of needing to be fed manually.
This electrical arc feeds from the contact point straight into the work metals and back, superheating them and melting them enough to fuse into each other.
The only foreseeable major downside of Mig welding is that it isn’t powerful enough to join truly thick pieces of metals, and it lacks the extreme precision of more expensive forms such as Tungsten Inert Gas Welding.
Gas Metal Arc Welders are versatile, with the ability to join a wide variety of thicknesses and materials, and they keep mess and weld spatter low. If you’re starting out, unsure of what to get, or won’t be needing your welder for any specialised jobs, this is usually what you should pick.
Tungsten inert gas welders
These are commonly referred to as GTAW or ‘Tig’ welders. Instead of the spool of wire used in Mig welding, Tig welders use a stable tungsten piece as an electron, and must manually supply the filler (if needed) by hand or through another apparatus. They operate off similar mechanics to Mig welders other than the spool, although they’re usually foot-pedal controlled.
Tig welding is easily the most expensive type of welding, and for that reason it’s unsuitable for most home or small setups, as it simply isn’t needed outside of very precise constructions. It’s also probably the most complicated of the setups, as unlike Mig it requires control of not just the metal and the welder, but a separate filling instrument.
When it comes to precision though, there’s none better. Tig is the industry standard when it comes to objects that must be infallible in their perfection, such as aerospace engineering.
Shielded metal arc welders
Commonly referred to as SMAW or Stick. Stick, much like Mig, uses a consumable electrode rather than a fixed one, but uses flux much like an old-style blacksmith. The flux evaporates under the extreme heat of the electrical current, which releases a gas much like a Mig welder along the weld seam.
Stick welding is the most common form of welder in repair work, as it’s simple, can work with most materials, and more easily transportable than Mig due to the differences in gas -- with Mig, you’re carrying around actual gas, rather than a solid coating which evaporates on use.
Stick is the least expensive option of the three here, and the best for quick spot repair for a tradesman or repairman. It doesn’t have the finesse of Tig, takes a little more time to master than Mig, but is an easy contender for most jobs.
Outside of the big three, there are a few other types that it can be handy to know of.
Flux-cored arc welders
These are fast, and often used in projects where time is at a premium. The main difference between FCAW and Mig is that FCAW uses an electrode with a hollow, flux-filled centre. While Mig supplies gas, FCAW supplies flux (the purpose and difference of which we’ve outlined in Tig).
This makes it more portable than Mig, and also more able to be used in volatile conditions such as outdoors or under wind. For this reason, it’s used a lot in construction projects. The only real downside of this method is its complete inability to weld the majority of non-ferrous metals.
Submerged arc welders
Submerged arc welders (SAW)’s primary advantage is its safety. It uses a process where the arc hits below a large layer of complex flux (hence the submerged), melting it to release shielding gases and simultaneously providing a conduit between the electrode and metal in one. Because of this, it’s very safe; there’s less radiation emission, less visual harm (though it’s still a legal requirement to wear a helmet), and not much spatter.
Solid state welders
A type of gas welding, solid state welders (SSW) meld materials before they reach their melting point without the use of any outside agents or flux. It’s a fairly finicky process, requiring knowledge of the exact timing and temperatures for materials, but works well for things that can’t be exposed to huge heats.
Choosing your equipment
Welding is not something that you want to begin without ensuring you have the right equipment and taking all the necessary safety precautions. As safety during welding and the equipment that you’ll need are often one-and-the-same, there’ll be a little overlap in explanation between these segments; however, it’s important that you know not just what to use and the laws and risks necessitating it, but are also intimately familiar with each individual piece of equipment. You’ll need to know its precise application, what it should never be used for, and it’s limitations before beginning work.
That said, most of the equipment that you’ll be using outside of the welder itself is fairly simple, and a lot of it is common sense (welders are bright and can cause eye damage, therefore wear a helmet and glasses, etc).
You are required by law to weld with industry compliant gear. Keep in mind that all gear must be pursuant to Safe Work Australia (pg. 23)
- Suitable for the nature of the work and any hazards associated with the work
- A suitable size and fitted reasonably comfortably for the person wearing it
- Maintained, repaired or replaced so it continues to minimise the risk, and
- Used or worn by the worker, so far as is reasonably practicable.
Furthermore, if you employ or instruct others in welding in any capacity, you must also provide your worker(s) with “information, training and instruction in the proper use and wearing of personal protective equipment; and (in) the storage and maintenance” of it.
A full list of compulsory gear is as follows:
Head covering: Without a welding helmet or goggles, you can suffer anything from permanent eye damage, burns from slag or weld spatter, sparks catching on your clothes or hair, or harm from radiation. To this end, you need compliant goggles or a helmet with protective filters over the eyes.
Hearing protection: Many welders make a lot of noise, and in some cases you may be required to have goggles or ear muffs (from flame retardant materials) to prevent hearing loss.
Hand covering: Gloves or gauntlets protect from burns and radiation and should go far enough up to minimise harm to the wrists and upper arms.
Flame retardant clothing: There are two parts to this. Firstly, you should only wear clothes made of natural fibres - this is because many synthetic materials, when exposed to extreme heat, will not only catch on fire but melt, effectively grating themselves onto the skin. This is not a pleasant thing to have happen, and complicates the burn immensely.
Secondly, clothing should also be heat resistant if possible, and have a minimum number of exposed pockets or bunches that could capture a rogue spark or piece of hot metal.
Foot protection: Boots must be fire and heat resistant as well as grounded in order to protect against electrical shock. Non-slip is also compulsory due to liquid metal in the environment.
Screens: If there is anybody remotely nearby to you who could foreseeably be affected by the visual, auditory, or physical dangers of welding, you must have translucent\opaque industry approved screens to prevent undue exposure.
Respiratory protective devices: Finally, this refers to facial or air-supplied respirators that protect your face against “dust, hazardous fumes, gases and chemicals, and oxygen depleted atmospheres”, which not only can cause lung damage but also involuntary responses such as coughing (involuntary actions are something that should usually be avoided when possible while superheating metals).
Each of these must be individually fitted and decontaminated between operators.
BJ Bearings stocks a wide range of compliant protective welding equipment in our range. Our personal recommendations include:
For helmets or face-shields, the WIA Auto-darkening helmet is compliant for all welding types, comes with an in-built Grind Mode for weld prep, and transitions from a high-visibility bright mode into a darkened safety mode when an arc is struck in under 1\10,000 of a second.
As for welding jackets and flame retardant clothing, we stock the Techware Maxisafe Pyrovatex, a 350GSM heat-resistant jacket with a safe, clippable quick-removal made of cotton-drill and Kevlar seamed. While it’s optional, anybody doing any work that requires putting their knees on the ground might also want to consider Kneepads to provide extra protection at the same time.
For gloves, The Techware Maxisafe Synthetic Riggers are an inexpensive and ergonomic design that doesn’t have bulky knuckle-bars and remains elastic and breathable.
When it comes to respirators, the Techware Maxisafe Respiratory Kit for Welders fits easily under just about all welding helmets (including the one above), and works as a P2 respirator for anybody that requires one due to their situation.
For anything else, you’re welcome to browse through our catalogue, and pieces such as boots or ear guards can generally be purchased from any work-clothing store. Just make sure they’re made to industry standards and materials.
Hazards and safety
As you might imagine, there’s an extreme amount of hazards that come alongside welding. We’ll list the main ones, but a large amount more inevitably stem from simply not following correct OHS procedure in general.
Make sure you’re up to date on all the extant rules and regulations for your workplace or home before you begin use of a welder to ensure your safety and that of others.
Threat: All welders emit some kind of radiation - Gas emits light and infrared radiation, with Arc\Laser Welders additionally emitting ultraviolet radiation.
Risks: Exposure to radiation differs upon the type, but is not limited to:
- Eye conditions, including ‘Welders Flash’ or even permanent impairment or blindness
- Skin and radiation burns
Precautions: Fortunately, the vast safe majority of radiation can be reduced by wearing the necessary safety equipment, as well as protective screens and distance away from anybody not wearing it. It’s mainly due to radiation and fire risk that we recommend resistant welders clothing.
Fumes, gas, and dusts
Threat: There’s a multitude of potentially threatening airborne contaminants associated with welding, from common dust to potentially harmful carcinogens. Not all of these fumes are visible to the naked eye, either - many are invisible gases, or can be masked easily by other things.
Risks: Exposure to pollutants and other contaminants in the air can lead to:
- Coughing and wheezing (which might not seem like much, but can easily impair or put at risk anybody operating a welding torch) through getting dust trapped in both the throat and lungs
- Lightheadedness, and in extreme cases asphyxiation
- Inflammation of asthma
- Permanent lung damage
- Explosion or fire (upon outside, flammable chemicals coming into contact with heat)
Precautions: As always, protective gear such as a breathing apparatus will eliminate a lot of the risks involved. However, you should make sure that there are no gaseous emissions from anywhere else in the vicinity, and keep any and all contaminants away from yourself while welding.
Welding within a ventilated isolation booth is a major way to reduce pollutant exposure. The HSIS (Hazardous Substances Information System) outlines the maximum amount that a worker or bystander can be exposed to during both an 8-hour, peak limit, and short term period in this document.
Fire and molten metal
Threat: When working with flame, things can (obviously) get burned. You’d be amazed at how many people still fail to take the necessary precautions despite this.
- Risk of asphyxiation from smoke
- Loss of property
- Loss of life
- Additional long-term injury from melded clothing
- Explosion due to outside chemicals
- Radiation due to outside chemicals
Precautions: Never put anything flammable, whether a manual or a placemat, near your welding torch, nor anything that might catch a spark and transmit it to anything flammable.
Wear flame-retardant, natural clothing that can be easily removed in case of burning. Do not wear anything that liquid metal could accidentally become lodged within.
Never use flammable gases or other materials near to where you are welding, and do not under any circumstances soak any resultant fires without both knowing the origin point of the fire and the correct extinguisher to use. In a worst case scenario, you’ll simply make the inferno larger, putting more at risk.
Threat: Much in the same way as fire, a welding setup presents an obvious and apparent risk of electrocution or of electrical hazards from both the environment and the tool itself. For anybody with medical conditions requiring bionics, an electrical shock represents a double threat.
- Electrocution, leading to burns, loss of mobility, or death.
- Electrical fires, which without correct procedure can run rampant without a means to control.
- Damage to pacemakers, causing them to malfunction.
Precautions: Firstly, you should wear grounded boots or otherwise ground yourself at all times to protect against both static electricity (which could ignite) and electrical shock. You should additionally make sure that all cords are in immaculate condition, without any signs of wearing, and that they aren’t a tripping or melting hazard (even if they’re already fully insulated and heat resistant).
Never place your welder upon conductive surfaces, even when not in use (except, obviously, pressing the tip to the metal), which includes areas that are damp - including dampness from condensation or under a humid atmosphere. Additionally, never let any water come anywhere near it. Make sure your sockets and plugs are all in working condition, and don’t tempt fate with anything frayed.
As there’s always a slight chance that, no matter the precaution, something fails, always work within eyeline of somebody else.
A circuit breaker will additionally prevent any overload-related incidents.
Threat: Welders emit a loud amount of noise, capable of damaging the human ear. For this reason, safety muffs are required.
- Temporary or permanent ear damage
Precautions: Wear earmuffs if your welder emits noise higher than WHS regulations allow for. For other in the vicinity, either work in a ventilated isolation booth, or put up appropriate noise-screens that will absorb it.
Choosing a welder
While we’ve already outlined the basic pros and cons for each welder type, as well as who they’re most suited for, you’ll ultimately still need to choose one before you can begin welding.
Just to recap, most hobbyists or indoor shed welders are going to probably want to use Mig (depending on the type of material) for its ease of use and relative safety. This can vary hugely though depending if you have a specific thing in mind that you need to weld, or are just buying one for multi-purpose.
Mig is a great starter for those circumstances, but make sure to consult a manual or ask a professional about specific materials and thicknesses. You can find our Mig line here, though the UNIMIG mini 180 is a great starting point.
If you’re looking within a budget, and already know the ropes, Stick is the best bang for your buck. It’s ol’ faithful - cheap and reliable, if a little slow. It’s also a lot better if you’re using your welder outdoors, or need to transport it a lot.
Tig is for pros, and people who need finesse. If you need the best weld that you can get, and have the knowhow behind it, you can see our range here.
Keep strongly in mind throughout choosing a welder that each type has its limitations on both material, thickness, speed, safety, and durability. A lot of material and thickness limitations can only really be known by a professional, so make sure that you do the necessary research for your own circumstances before making a major purchase.
As always, it’s vitally important to also buy safety equipment before commencing even a test of your new welder. Don’t skimp on the safety; welders are dangerous instruments!
Tips for beginner welders
Welding is an excellent skill to have, whether you’re involved in the construction industry, have equipment you need to repair or want to save money repairing your car. Taking the correct safety precautions, using common sense and having appropriate, high-quality equipment and materials are key to welding success.