Welding Equipment Buying Guide, Supplies and Manufacturers
Welding involves joining together two pieces of metal, using a filler metal, through the processes of melting and fusing. Typically, both of the pieces of metal that are to be joined are melted, and additional molten metal or plastic is added in between the two pieces in order to strengthen the bond. A welder must provide enough energy to fuse the metals together. Usually, this energy comes from an electric arc or from a flame, such as an oxyacetylene flame. The heat that is produced during welding is usually within the range of 1500 to 3000 degrees Fahrenheit. Soldering is an alternative means of connecting metals, which uses lower temperatures. During the welding process, enough heat is used to melt the metals that are being joined as well as the filler material.
You should try to match the type of welder which you choose with the types of welding work that you are going to be doing. Different types of welders are better at different types of job. Some of the most common uses for a welder are in construction, home repairs and car repairs. You need to make sure that the welder you choose is suitable for working on the right types and thicknesses of metals.
Resistance Spot Welding is a method that does not require much skill. These welders are easy to use and they are usually very portable. They work using a current that moves between two electrodes, one on each side of the pieces of metal that are being joined. The pieces are joined because of the resistance of the metal itself to the passing current, rather than with an arc. Steel and stainless steel are the most suitable metals for this type of welding.
Shielded Metal Arc Welding or Stick welding involves the use of a replaceable electrode as a support for the arc. Filler metal comes from the center of the electrode, while the melted outer coating of flux provides shielding. Stick welding works well outdoors, even when it is windy, and it can be used on metal that is dirty or rusted. Stick welding is ideal for use with cast iron, steel and stainless steel. It requires a moderate level of skill.
Gas Metal Arc Welding or MIG welding joins metals using an arc between the workpiece and the solid wire filler metal electrode, which is constantly being supplied by a wire feeder. The contact end of the wire is electrically charged, and it melts into a puddle as the trigger of the welder is used. A shield of inert gas, such as argon, helium or carbon dioxide, protects the weld from contamination. This type of welding requires little skill and is easy to learn. It is much easier to control when welding thin metals and it produces clean results with very little slag to be cleared off. It is also possible to use a MIG welder for flux cored welding. MIG welding is suited to cast iron, steel and stainless steel, and aluminum.
Gas Tungsten Arc Welding or TIG welding involves the creation of an arc between the workpiece and a non-consumable electron made of tungsten. They are similar to MIG welders, expect for this tungsten electrode. Filler metal is used sometimes, but not always. An inert gas mixture, which may be Argon gas, is used to provide shielding. This method can produce high quality and attractive results, but it does require a lot of skill. It can be used on more types of metal than any other welding process. It is suitable for use on aluminum, titanium, brass, copper, gold, steel and stainless steel, and alloys of magnesium.
Flux Cored Arc Welding or Gasless welding is another low skill form of welding that uses a machine with a wire feeder. The metals are melted using an arc that is formed between the workpiece and a consumable electrode. Flux core welding produces a tubular weld with the flux material lying within the shielding. Self shielding wire works well in windy conditions. An additional gas shield can sometimes be used, depending on the type of flux cored wire that is in use. This technique is a good option for use on steel and stainless steel and it is suitable for welding thick sections of metal since it provides deep penetration. It can also be used on rusted or dirty metal.
Gas shielding welders can be easier to use and they can produce tidier results, so they make a good choice unless you only want to use flux cord welding. Gas shielding keeps oxygen away from the weld. This can prevent spattering and makes it much easier to see what you are doing. Gasless welding is usually cheaper since there is no need to buy gas, and it can be a good option if you need to work outdoors, but it can be more difficult to master.
Welders may be either gas powered or electrically powered. Electrical welders can be convenient when power is available within range of the power cord, although you will have to cope with a cord that may get in the way. Gas powered welders can be used anywhere, regardless of whether or not there is an electricity supply, but they do need to be provided with gas.
The more powerful your welder, the thicker the metal you will be able to weld, although the type of welding which you want to do will also affect the thickness of metal that it is possible to join. You need to consider both the minimum and the maximum amount of power which the welder can produce since this will determine the range of thicknesses of metals which you can weld. Using a welder that is too powerful for a particular job can be just as bad as using one that is not powerful enough.
The Duty Cycle of a welder reflects the length of time for which you can use the welder before it overheats. It is measured as a percentage of a five or ten minute period, depending on the manufacturer. A welder with a 60 percent duty cycle for 100 amps over ten minutes can be used as this power for six minutes before overheating. It will then need a break of four minutes. Smaller welders that lack fans tend to have lower duty cycles, so you should choose a welder with a fan if you need to be able to use it for a longer period without a break.
Some welding torches are permanently live, which means that if you accidentally touch something with the torch, it could be seriously damaged, and if you are not wearing your visor, you could also harm your eyes. Most modern welders are designed with a contactor that controls when the torch is live, but there are still some permanently live torches out there, which should be avoided.
If you are willing to spend a little extra, then it is worthwhile looking for a welder with an automatic wire feed control, which will change according to the amount of power being used. The setting can still be fine tuned manually, but it is not necessary to change the wire feed setting when changing power settings. You should also consider the quality of the wire feed mechanism and motor when choosing a welder since a better mechanism will make using the welder much easier.
Another feature which may appear is a burnback control, which can be used to regulate how much the wire burns back after welding. This can be a useful feature when you are working with thicker metal and you could otherwise end up with a long piece of wire that will need to be trimmed.
Some welders also feature spot timers that can cut off the power after a set time when spot welding.
The portability of a welder can be an important consideration. If you choose a welder that is very portable, you will be able to bring it to the pieces of metal that need to be welded, rather than having to carry the metal to the welder. Using a portable welder can be more convenient if you are working on large pieces of metal that it may not be possible to move. It is often possible to buy accessories to help make a welder more portable, however. Most handheld portable welders will weight less than 70 pounds and be easy to carry about. Larger welders can still have some mobility, particularly if they are set on wheels.
Welding torches are usually supplied with welders, but they can also be purchased separately, for example as a replacement for a worn out torch. If you choose a welder with a built-in torch you will only be able to obtain replacements from the original manufacturer, which will be expensive. If you believe you may use your welder enough to cause sufficient wear that you will need to replace the torch at some point, it is a good idea to choose a welder with a universal connection for the torch.
A gas regulator is a useful piece of equipment that can measure the amount of gas that is used. The cheapest regulators only measure the amount of pressure that remains in the gas bottle, but the slightly more expensive dual gauge regulators can also show the flow rate. This can help you to ensure that you use your gas as slowly as possible.
As well as choosing the right welder, it is important to ensure that you have the safety equipment you need to ensure that you will be properly protected while you are welding. The most important item of safety equipment for welding is the welding helmet. You should make sure that you have a suitable protective helmet before you start to use your new welder.
Some welding helmets have auto-darkening glass, which reacts instantly to the light of welder in order to protect the eyes. While the welder is not in use, the glass remains clear so that you can see clearly. An auto-darkening welding helmet can be easier to use because it can be left in place. When using a standard glass helmet, the visor needs to be moved into place before you can start welding, and then flipped back to enable you to get a better view. This can be inconvenient, particularly when working in a small space where it may be difficult to open up the helmet, and it can even lead to the loss of the right torch position as you pull down the visor when you begin welding.
When choosing a helmet with a reactive lens, it is important to ensure that the lens reaction time is as quick as possible. Even a tiny delay in the reaction could lead to damage to your eyes and some discomfort since they will be exposed to the high intensity of the light. Reaction times are typically between 1/25,000 of a second and 1/12,000 of a second.
A protective welding helmet should meet the required standard of protection, ANSI Z87.1-2003. A helmet that matches this standard will be able to protect the eyes against ultraviolet and infrared light, even when the glass is not darkened. Meeting this standard shows that the helmet has passed independent safety testing, which measures its ability to protect you against impacts, UV and IR light and to switch color quickly, even in extreme temperatures.
The shade on a welding helmet can be either fixed in place or adjustable. An adjustable helmet can be useful if you need to be able to weld using different types of processes, such as stick welding, TIG and MIG, since the shade can be adjusted in order to get the best view. If you always weld the same type and thickness of material, then a fixed shade can be adequate.
Some helmets offer additional features. The adjustable sensitivity feature enables you to change the amount of light that is required to trigger the lens reaction. The delay setting can be used to make the lens remain dark for a while after the light of the welder goes out.
Helmets can be battery powered, solar powered or use a combination of both sorts of power. Battery powered helmets can be used immediately, while a solar powered helmet will need to be charged before its first use, or if it has been in storage for an extended period. A dual powered helmet offers the best of both worlds since you can use it straight away, but you can also enjoy free solar power.
Other safety gear that you may want to invest in are some thick welding gloves or gauntlets to protect your hands, and cotton overalls to protect your clothes.