How To Stick Weld Stainless Steel

Stainless steel is a highly hygienic, clean, strong, and corrosion-resistant metal that is widely used in applications across the fabrication industry. It has various advantages over carbon steel, but many find it more challenging to weld.

Welding stainless steel is often considered a task for more experienced welders. It can indeed be more challenging than other metals, but with a bit of effort and the right approach, you can master this skill with any popular arc welding method.

Today, we will take a closer look at SMAW welding stainless steel. Although this is not the first choice, we'll give you tips and tricks on how to Stick weld stainless steel.

Stick Welding Stainless Steel Using E309L Electrodes
Source: https://www.youtube.com/watch?v=bwG5ajGpf98

Can You Stick Weld Stainless Steel?

Yes. You can use Stick or Shielded Metal Arc Welding (SMAW) to join stainless steel pieces or weld stainless steel to carbon steel. But many consider it a highly challenging task, and we will explain why.

The key to successful stainless steel welds lies in understanding its properties. By reviewing these properties and the very nature of SMAW, you'll realize why Stick welding this metal can be a nightmare for less experienced welders.

Let's further explain the basics and potential challenges.

Vertical Stick Welding of Stainless Steel with 309L-16 Electrodes
Source: https://www.youtube.com/watch?v=YZHZPdK9PT8

Basics of Stainless Steel

Stainless steel is a corrosion-resistant alloy of iron, chromium, and, in some cases, nickel and other metals. Its many favorable properties make it a valuable part of industries worldwide.

Compared to mild steel, stainless steel resists corrosion, maintains strength at extremely hot and cold service temperatures, and provides better aesthetics. The most advantageous characteristics of stainless steel are:

• Excellent corrosion resistance

• High tensile strength

• Maintains good properties at extremely hot and cold temperatures

• Good weldability

• Low susceptibility to bacterial growth

• Excellent weld aesthetics

As a result, stainless steel is widely used in the piping and petrochemical industries, food preparation and medical equipment, and rail and trucking industries. You can encounter stainless steel in your everyday welding in exhaust parts, outdoor railings, pipes, and more.

Stick Welding Stainless Steel Exhaust
Source: https://www.youtube.com/watch?v=A5sJ23Xes_w

Stainless Steel Grades

There are multiple grades of stainless steel depending on the amount of chromium and other alloying elements. Knowing the grade of the stainless steel you are welding is crucial in weld preparation and choosing the right electrode for the work.

Source: https://www.toptitech.com/

The three primary types of stainless steel are:

• Austenitic: This is the most prevalent type of stainless steel you are likely to encounter in your everyday welding. Austenitic stainless steel contains chromium, nickel, manganese, or molybdenum as alloying elements, and they give it good weldability and corrosion resistance. Common grades you'll weld are 304, 310, and 316 stainless steels.

• Ferritic: Ferritic stainless steel has less nickel and more chromium and molybdenum, which makes it magnetic, hence the name. It is stronger than ferritic stainless steel, and common grades are 409, 430, and 444.

• Martensitic: This is hardened and tempered stainless steel, often used in cutting tools, medical equipment, and knives. The standard grades are 410, 420, and 440, but you are less likely to weld these at home.

Source: https://www.youtube.com/watch?v=B0ZfDJhLgmg

What Makes Stainless Steel Challenging To Weld?

While stainless steel offers various advantageous properties, its structure and alloying elements pose several challenges. Stainless steel has low thermal conductivity and a high thermal expansion rate, which makes heat control crucial.

Low thermal conductivity means alloying elements retain heat longer rather than dissipating it. The heat is concentrated in the weld pool, which causes overheating, warping, and distortion. High thermal expansion causes stainless steel to expand when subjected to heat. Once the pieces start cooling, they can warp and crack.

Stainless Steel Sheet Warpage from Stick Welding
Source: https://www.youtube.com/watch?v=RFIZFYjaOog&t

You might have heard some older welders say that stainless steel can warp or distort, even if you look at it wrong. These properties are the leading causes of warping and distorting.

Additionally, overheating stainless steel causes discoloration or sugaring. Heat exposure and other factors pull out chromium from stainless steel, resulting in colors on the surface. While this is favorable in welding art, colors are a sign of oxidation, meaning the metal has lost some corrosion resistance. The darker the color, the thicker the oxidation.

Overheated Stainless Steel Causing Discoloration
Photo by @sewingwithfirewelding (TikTok)

Shielded Metal Arc Welding and Stainless Steel

Stick or Shielded Metal Arc Welding (SMAW) is one of the oldest welding methods. It uses self-shielded electrodes and the heat of an arc to melt and fuse pieces. The Stick is ideal and cheap for outdoor or home repairs, and as we said, you can use it to weld stainless steel. But you should know there are some limitations.

Firstly, Stick welding does not work well with thin sheet metal. SMAW arc runs hot, so trying to weld thin stainless steel pipes or pieces can cause burn-through, even at the lower end of the amperage. Therefore, consider using Stick only for medium-thickness or thick pieces of stainless steel.

Stick Welding Stainless Steel Pipe
Source: https://www.youtube.com/watch?v=khN1e1fMDbM

Secondly, Stick welding is not known for heat control. The high heat caused by the arc, combined with the thermal properties of stainless steel, can cause overheating, warping, distortion, or cracking on the thicker pieces.

Lastly, stainless steel electrodes and stainless steel itself are pricier than mild steel. Thus, producing faulty stainless steel welds can be time-consuming and expensive. That's why many leave Stick-welding stainless steel to seasoned welders. But with a bit of practice and knowledge, you can finish your home repairs.

Stick Welding Stainless Steel Stair Railing
Source: https://www.youtube.com/watch?v=wvsQsLTsdAU

Step-by-Step Guide on How to Stick Weld Stainless Steel

Stick, or SMAW, is a relatively simple and quick welding method. However, welding stainless steel requires good weld preparation, correct technique, and the right electrode for the job.

Each piece of the puzzle plays a crucial role in producing strong, defect-free stainless steel welds. Therefore, you should follow our step-by-step guide to make sure you are0 doing everything right.

Stick Welding for Stainless Steel Residential Translation Gate
Source: https://www.youtube.com/shorts/xw_WK7NNLN4

Step 1: Choose the right Stick electrode

The first step in yielding strong and defect-free stainless steel welds with Stick is matching the electrode type, coating, and diameter to the stainless steel grade. By doing so, you can be sure your electrode properly fuses and penetrates the pieces.

Stainless Steel Stick Welding Process
Source: https://www.youtube.com/watch?v=rXJT-26eRJc

Electrode Type

There are dozens of electrodes designated for stainless steel welding and different grades. However, you are likely to weld austenitic stainless steel in your everyday welding applications. Therefore, you will need one of the following electrodes:

• E308/308L: These are some of the most common electrode choices for most austenitic stainless steels. They have extra low carbon content, and typical applications include welding type 304L, 321, and 347 stainless steel or 200 series.

• E316L: These electrodes have up to 0.04% carbon, and welders use them to weld type 316L or type 316 stainless steels. This electrode is widely used in the welding of chemical equipment.

• E309L: 309L electrodes are designed to weld heat-resistant base metals of similar compositions. Welders frequently use this type to weld stainless steel to mild steel or other dissimilar joints between stainless steel applications.

Types of Stainless Steel Welding Rods
Source: https://onetouchexim.com/types-of-welding-rods-for-stainless-steel/

Electrode Coating

Stick electrodes have a flux coating that is crucial in protecting the weld. As the flux melts, it creates a protective layer of slag that shields the molten weld from contamination. Besides flux, electrode manufacturers add other elements to enhance their performance and improve arc stability.

Stainless steel electrodes have three types of coating that affect welding performance and results:

• Lime-coated stainless steel electrodes: These electrodes are identified by the suffix 15 (e.g., E309L-15). They produce thin, fast-freezing slag that works excellently in overhead or vertical positions. However, slag can be hard to clean, and these are DCEP-only electrodes.

• Titania-coated stainless steel electrodes: These carry a suffix 16 (e.g., E309L-16). They produce stable, clean arcs and work great in flat and horizontal positions, making them one of the most used in stainless steel welding.

• Silica-titania-coated stainless steel electrodes: Electrodes with this coating carry a suffix 17 (e.g., E309L-17). They work great with DCEP, provide good wetting, and produce smooth, concave welds.

Stick Welding Stainless Steel Pipes with E309L-17
Source: https://www.youtube.com/watch?v=YZHZPdK9PT8&t

Electrode diameter

Electrode diameter can also affect welding performance, as larger electrodes require more amps to run. Higher amperage means more heat and deeper penetration, but you'll need to be careful with stainless steel.

Stainless steel electrodes are available in standard diameters, such as 3/32 ", 1/8", or 5/32". The rule of thumb when choosing the diameter size is to use an electrode one size down from the material thickness. For stainless steel, you can even go with an electrode size of half the material thickness to limit the heat, but don't forget about penetration.

If the stainless steel thickness exceeds 3/16", you'll need to consider other factors, such as position, joint configuration, or weld size. However, limiting the heat for stainless steel means limiting the amperage and, thus, the size of the electrode.

Vertical Up Stick Welding with 3/32" E309L
Photo by @diegoneira398 (TikTok)

Step 2: Clean stainless steel

Welders often use Stick welding to burn through light layers of surface contamination. Doing so allows them to finish the job quicker, and deep-penetrating electrodes burn away all contaminants from the surface.

However, there is no room for compromise when Stick welding stainless steel. You must thoroughly clean the surface before welding and remove any oil, dirt, chalk, or grease. During stainless steel welding, these contaminants can get trapped or damage the protective layer and affect the corrosion resistance, so it is crucial to remove them.

Clean Stainless Steel Surface
Source: https://www.youtube.com/shorts/now12OIf5s8

Be careful when handling or cleaning stainless steel. Scratches or bumps can create weak spots prone to corrosion. If you are using a wire brush, rotary disks, or power tools, make sure they are designed to work with, or made of, stainless steel. A carbon steel wire brush will contaminate the surface and promote corrosion.

If you are multi-pass welding stainless steel, make sure to clean the slag after each run. Slag inclusions can create weak spots that affect the structural integrity of the weld and affect corrosion resistance.

Clean the Slag After Welding
Source: https://www.youtube.com/watch?v=rXJT-26eRJc

Step 3: Joint preparation

Once you have cleaned the pieces, you'll need to prepare the weld joint. For home Stick welding stainless steel, we suggest sticking to horizontal or flat butt welds. Flat welding is the easiest welding position, as gravity works for you and pulls the weld puddle inside the joint.

Stick welding thin stainless steel is generally not recommended, but if you need to do it, you should be careful. To limit the warping or distortion, you should add the chilling bar on the back side of the joint. The chilling bar will help with heat dissipation and prevent overheating.

When Stick welding thick stainless steel pieces or pipes, you should bevel the edges and use multiple passes. Multi-pass welding takes more time, but it is more suitable than using large electrodes and high amperage on stainless steel. Bevel the edges to 60 degrees, or according to weld specifications, and create a root opening with the same size as the root face.

Bevel edges and use multiple passes for thick stainless stick welds.
Source: https://www.youtube.com/watch?v=tqt-bbBLSFA

Step 4: Set up the welder

You can weld stainless steel with any home Stick welder, such as the YesWelder ARC205-DS Pro. However, as we mentioned several times, you should be careful with the amperage.

To Stick weld stainless steel, you should use a 1/3 lower amperage than you would typically do for mild steel. Keep the amps low enough to get the arc to start and continue across the joint without extinguishing or the electrode sticking to the metal. If you notice distortion or warping, you are probably running too hot.

You can observe the electrode after the welding to dial in the machine. If you are practicing on scrap metal, look at the electrode right after you finish the weld. If the electrode is red down to the stub, the amperage is likely too high. But remember that you will still need the proper penetration to produce sound welds.

Observe the Electrode After Welding
Source: https://www.youtube.com/watch?v=ZmLbwN2AkYg

Step 5: Practice the technique

The key to successful Stick welding on stainless steel is to use the correct technique for the job. If you fail to run your welds right on stainless steel, the entire preparation, cleaning, and dialing-in will be in vain.

The first rule any seasoned welder will tell you when trying to Stick weld stainless steel is to keep the arc tight. The tip of your electrode should be as close as possible without touching the puddle. Short arc length produces low voltage, making your weld puddle thinner and easier to control.

Vertical Stick Welding Stainless Steel
Photo by @diegoneira398 (TikTok)

You want to be almost 90 degrees to the weld with a slight angle as you drag. Use the correct travel speed and torch angle to avoid slag inclusions, which are typical for beginners trying to weld stainless steel. If you are using YesWelder Stick/Arc machines, turn up Arc Force Control to get an even more focused arc.

To prevent heat exposure, avoid welding beads that are too long. When welding thinner stainless steel pieces, use several shorter stringer beads. However, if you multi-pass weld thicker stainless steel, you can use a slight "J" weave motion to flatten the bead and provide a good tie-in. Flat beads yield slag that peels easily and prevents slag inclusions.

Remember to fill the crater. A crater is a small hole that appears at the end of the weld if you prematurely finish by removing the electrode from the joint. To fill the crater, move the arc back over the end of the weld. 

Weld Crater in Stick Welding
Source: r/Welding on Reddit

Step 6: Vertical Stick welding stainless steel

Vertical or overhead Stick welding stainless steel is a very challenging task that is reserved only for the most experienced welders. In general, stainless steel for SMAW is not recommended for more than 10º uphill.

But if you have to do some quick repairs, here are some tips that can help. Like with flat stainless steel welding, keep the arc as tight as possible. Use smaller diameter electrodes up to 5/32" to limit the heat. Look for electrodes with a fast-freezing puddle to stop the molten metal from dripping down the joint.

When welding thin stainless steel, you can weld vertically down. In downhill welding, you can get enough penetration and heat by dragging down the electrode. But remember to increase the heat to provide good penetration. However, Stick welding thicker stainless steel downhill can result in a lack of fusion and penetration.

Vertical Stainless Steel Stick Welding
Source: https://www.youtube.com/watch?v=gOrUgNv9a9c&t

Step 7: Clean the welds

After finishing the weld, remember to clean the slag and spatter. Failing to clean the slag, especially in multi-pass welding, will trap it inside the weld. Slag inclusions are a frequent cause of weld failure on stainless steel SMAW.

Wait for the welds to cool, then chip the slag with a chipping hammer for stainless steel only. Then, use a stainless steel brush to remove the remaining leftovers.

Stick welding produces some spatter. You should clean it to improve aesthetics and protect the surface from rust. If you are seeing excessive spatter, your settings or welding technique might be wrong, so try playing with your welder.

If you see darker colors on the surface, use brushing, pickling paste, acid baths, or electro-polishing. Besides aesthetics, removing colors is crucial in avoiding further oxidation and rust.

Pickling for Stainless Steel
Source: https://www.youtube.com/shorts/Mjry-Lmq3yg

Quick Tips on How to Stick (SMAW) Weld Stainless Steel

Instead of a typical summary, we made a list of quick tips based on everything we learned about Stick welding stainless steel today. Here are the essential tips on how to Stick/Arc weld stainless steel:

Turn & Burn Stainless Steel Stick Welding
Source: https://www.youtube.com/shorts/X59bBlm2iXQ

• Use Stick welding primarily for medium-thickness or thicker stainless steel.

• Avoid welding thin stainless steel sheets with SMAW to prevent distortion, warping, cracking, or burn-through.

• Match the electrode composition to the stainless steel grade you are welding.

• Use one size smaller electrode or even half the thickness of the stainless steel to reduce heat exposure and prevent overheating.

• Choose a smaller electrode diameter with a faster freezing puddle on vertical or overhead welding.

• Use electrode coating that matches your current welding position and joint configuration.

• Thoroughly clean the stainless steel before welding.

• Use tools, wire brushes, or discs designed strictly for stainless steel.

• Try to weld in a flat position whenever possible.

• Adjust joint design and geometry based on Welding Procedure Specifications.

• Use the lower end of the amperage to avoid heat build-up.

• Tune up Arc Force to get a more focused arc.

• Keep the arc tight to avoid slag inclusions.

• For the given thickness, position, and joint geometry, use the right travel angle, working angle, and travel speed.

• Use shorter stringer beads on thinner stainless steel.

• Use slight J-weave beads on thicker pieces and multi-pass welding.

• Fill the crater.

• Take special precautions when welding vertically or overhead.

• Clean the slag, spatter, and other debris after welding.

If you've done everything right, you can get satisfying Stick welds on stainless steel. Although you shouldn't expect TIG-like results, with a bit of practice, you can produce defect-free welds with Stick welding on stainless steel.

Food-grade 308 Stainless Stick Welding
Source: https://www.youtube.com/shorts/Rmtv9zhg5Qc