In this article, we will tackle the basics of welding MIG, TIG, and Stick. The purpose of this article is to provide an overview of the process involved for each. This article is intended for beginners looking to understand what welding is about or for veterans that need a refresher. Extensive training with a qualified instructor is needed to weld and do it the right way!
MIG Welding Overview
MIG welding (Metal Inert Gas, also known as Gas metal arc welding) is an arc welding process. A constant wire electrode is supplied through a welding gun, then goes into the weld pool, which joins together the 2 core materials.
A shielding gas also goes though the welding gun as a means of protecting the weld pool from getting contaminated.
Metal Preparation for MIG Welding
Stick and Flux welding electrodes are much different than MIG welding wire. One main difference is that MIG wire does not fight against contaminants like rust, scaling, or dirt all that well. You will need to use a metal brush to clean off the surface before striking the arc. You must also ensure your work clamp connects to clean metal also. If there is any electrical impedance, wire feeding will be affected.
MIG Welding Aluminum Steps
- Select the right machine for the metal. Thicker metal will need a more powerful machine. A 115 volt welder can handle aluminum up to 3mm so long as you preheat it.
- Pick out the right shielding gas. Aluminum will require you to use pure argon. You may need to replace regulators that were designed only for CO2 Use.
- Use the correct aluminum electrodes. A thinner wire will be a bit tougher to feed, while thicker wire will need greater current for smelting.
- Pick up a good aluminum feeding kit and feed electrodes with it. These kits are available for sale, and you will have an easier time feeding softer aluminum wire when you buy a kit that has large holes on contact tips, drive rolls shaped like a U, and non metallic liners.
- Make sure you keep your gun cable straight, so the wire feeds correctly.
TIG Welding Overview
Tungsten Inert Gas welding uses a tungsten electrode as a means of heating up the metal to be welded. As a method of protection against contaminating the weld during this process, shielding by way of inert gases like argon is utilised and is great for all metals and thickness.
The quality of TIG welds are second to none, and you can weld just about any metal. Copper, magnesium, brass, steel, gold, and bronze are just a few. The welds end up nice and clean, making your end result look professional and beautiful. A welder can easily increase and decrease the heat used in the process by making use of a foot pedal that helps control the weld. This type of welding also produces no sparks or fumes/smoke.
Common Applications for TIG Welding
- Autos - For a car to be safe, secure, and road ready, proper welding techniques must be used. This method also helps cars avoid rust, which is why most car fenders are often welded using this method. It helps cars stand up to wear and tear.
- Aircraft - Spacecraft and aircraft are prime candidates for TIG welding. Commercial planes used each day and even the International Space Station all feature assembly that involved TIG welding.
- Fixing Things - This method of welding is great when you need to make a fix on something around your home. You could repair some aluminum tools, for example.
TIG Weld Aluminum Steps
- Make sure your hand placement and control are spot on. Clasp the torch by securing it using the base of the hand flat on the table. Now keep it in a stable forward position, keeping a slight 10-15 degree tilt.
- Keep close proximity from the tungsten to your project-a good rule is identical to the diameter of your tungsten up to about one-fourth inch. Pulling the tungsten too far away will spread the arc too wide and thus overheat the project.
- Without striking an arc, focus on working on the movement of the hand and the torch. Make sure to practise with safety gloves on as this is how experienced welders work. The trick is to have light force on your hand and a solid grip on the torch. Keep movements steady and even.
- You will notice that filler metal deposition happens ahead of your TIG torch as you press it forward. Keep your filler rod and torch at 90 degrees configuration to one another. Always push-never drag-a torch.
- On the leading edge of your puddle should always be filler metal.
Stick Welding Overview
Stick welding is also known as “Shielded Metal Arc Welding,” which a is a commonly used arc welding process, and it makes use of a fixed-length electrode plus a power source to weld together many different metals. The core of the covered electrode is made up of a solid metal rod which is surrounded by a mineral compound cover and various metal powders. These are mixed with a binding agent which helps them stick to the electrode's surface.
Then the core rod transmits electric current over to the arc as well as provides the filler for the joint. Depending on the size and type of electrodes you are using, your voltage requirements will vary - you can use anywhere from 16 to volts. Amperes will also vary, from 20-55 amps.
The purpose of the electrode covering is to provide some firmness to the arc plus shield molten metal from the air using gases created as the coating melts from the arc's heat. The shielding helps control the chemical composition, mechanical properties, and metallurgical structure of the weld metal.
Purposes For Stick Welding
- Stick welding can be used anywhere. You can weld inside, outside, a bridge, on an assembly line, or even on a pipeline. It is truly a versatile welding process.
- It is great for use when your access to the welding area is limited.
- It is great for use with common alloys and metals.
- It's not as sensitive to the wind compared to gas-shielded arc welding processes
Stick Welding Aluminum Steps
- Begin by getting your machine ready-it should have DC polarity and be able to put out at least 200 amps. Set the machine's current-remember; at least 200 amps is necessary to weld aluminum successfully. Depending on the thickness, you should set the machine to 190-210 amps.
- Now keep an eye on your arc's length. When you are stick welding aluminum, keep the arc length about the same as the diameter of your aluminum rod. Keeping the rod far away will increase voltage but leads to splatter, and keeping it too close lowers the voltage and lowers the quality of penetration.
- Keep the rod angled at about 15 degrees against the aluminum that is being welded. This will help ensure a clean arc. Keeping it at 25 degrees or greater will create poor penetration and lead to a weak weld. Drag the rod away - do not push into the weld - as this is a different process than MIG welding.
The art of welding is not something we can sum up in just one article. We encourage you to learn welding from an experienced welder or certified instructor so you can take part in this exciting craft.