The Ultimate Guide To SMAW & Stick Welding
Techniques, Tips & Process
What is SMAW welding?
SMAW welding is a process which uses a consumable electrode which is covered with a flux. The welding machine is hooked up to a power source, which creates either alternating current (AC) or direct current (DC) to form an arc between the electrode and the metal.
As this arc forms, both the electrode and the metal melt, forming a molten puddle known as the weld pool. At the same time, the heat from the arc burns off the flux, which forms a layer of gas to protect the weld from certain atmospheric gasses which can affect the weld’s quality. This negates the need for a separate tank of shielding gas – and without it you’d end up with weak, brittle welds.
As the weld pool cools, it solidifies to form a joint. This process also forms a layer of slag which has to be chipped off – which does make it less time efficient than many other types of welding – but choosing the right electrode can help to speed up the process.
Typically, SMAW welding is used for heavy-duty, industrial steel and iron jobs, but it can be used to weld aluminum, and other metals as well.
SMAW Welding Techniques
Before you actually start stick welding, it’s essential to get your hands on a welding helmet and other protective clothing, including jackets, aprons, and even boots. Aside from the blinding light from the arc and the heat which are both produced with this process, you need to be adequately protected from all the slag and spatter which forms.
Make sure that your metal is clean as any dirt and imperfections can affect the strength and quality of the weld. Next, fit your chosen electrode into the welder and select the appropriate amperage (read the manufacturer’s guidelines if you’re unsure about this) and you’re ready to weld.
To start the arc (and consequently the SMAW welding process), simply scratch the electrode sharply against the surface of the metal, then draw it away slightly. This should be done in one smooth movement. The arc will form between the metal and the electrode, and both will begin to melt.
In all welding positions, consider the effect that gravity will have on the weld pool before you begin. This is effectively a pool of molten metal so it will behave in a similar way to other metals, so make sure you position yourself correctly to weld as safely and effectively as possible.
Horizontal and vertical welds can both benefit from having backing plates and beveled edges, and in both cases, you should hold the electrode at 90° to the metal that you’re working on.
Overhead welds can be slightly more tricky in that you have to be careful of spatter and burns. Once again, backing plates can help. For flat welds you should hold the electrode at 90° to the base metal, but in any case you should always try to tilt it slightly to prevent any drips from falling onto your equipment.
Use a plasma cutter or a grinder to create beveled edges on thicker materials measuring more than 3/16″, while you can stick with a square groove weld for thinner metals.
Whether you’re doing square groove welds or V-groove welds, keep the electrode at right angles to the metal, but lean it in the direction that you’re welding. If you tilt it in any other direction your welds will be ineffective and the whole process will be awkward and dangerous.
For fillet joints, keep the electrode at a 45° angle to the weld. For lap joints, on the other hand, you should keep the degree much tighter, moving the electrode in a circular motion to enhance its strength. In both cases, you should aim to weld both sides of the joint in order to make it stronger and more durable.
While you’re still getting to grips with SMAW welding techniques, there is a number of problems which you might encounter. Part of the enjoyment of welding comes from trying out different things and practicing the art of welding until you’ve perfected it, but here’s a quick run through of some SMAW welding tips and tricks to get you out of various sticky situations.
When you’re trying to start your arc, your electrode might get stuck to the metal. Don’t panic: simply twist the electrode slightly and it will work loose, allowing you to try again.
Once you get underway, if you don’t move the electrode steadily and smoothly, your arc might break. This happens when you move the electrode too far away from the metal, so to correct it all you need to do is start again and make sure you stay the same distance away from the join. Working out the most appropriate arc length will help with this; read the manufacturer’s specifications and industry guidelines for details, but in general electrodes with a diameter of 1/8″ or more need an arc length of 1/8″, while an arc length of 1/16″ is more suitable for smaller electrodes.
If you’re not getting good penetration, this could be down to a number of factors, one of which is your travel speed. Move the electrode too quickly and your welds will be narrow and inconsistent; move too slowly and your weld pool will build up, giving you too much weld deposit. Getting the travel speed right will just take time and practice.
Finally, if your welds keep breaking, it might be a good idea to test them with a hammer to make sure they’re strong enough before you put away your equipment. Don’t hit the welds directly – aim your hammer for around two to three inches higher. Of course, it goes without saying that you should clean the slag off each weld before continuing or doing multiple passes.
All things considered, SMAW welding is a really simple process which doesn’t need excessive amounts of equipment. Clean your materials, then choose the correct electrode, arc length and weld speed, and you’re starting out on the right foot. Having read through these SMAW welding tips and techniques, you’re armed with everything you need to know – now learning to perfect strong, durable, high-quality stick welds is up to you!