Everyone that starts stick welding (SMAW) has a hard time because the welding rods frequently stick to the workpiece.
A rod mostly sticks when you try to strike the arc, and to a lesser degree while running the bead. Even experienced welders stick the rod from time to time. So why stick welding rods stick to the base metal?
A stick welding rod sticks because the arc’s heat is not high enough to prevent the fusion between the molten rod tip and the puddle. Having low amperage settings or an arc length that is too short are the main reasons.
After reading this article, you will know how to handle and prevent this problem.
Table of Contents
- What are the reasons that welding rods stick to the base metal?
- What to do when the welding rod sticks?
- How do you prevent a welding rod from sticking?
- How to fix the tip of a stuck rod?
What are the reasons that welding rods stick to the base metal?
First, let’s see the various reason this happens:
- First of all, low amperage settings on the welding machine.
- The distance between the rod and the workpiece is too short. We call this distance arc length.
- The machine cannot support the rods you try to weld with. For example, you are using DC+ rods with an AC buzz box.
- The rods have flux problems, for example, cracks or missing parts.
- There is an unstable current flow through the welding circuit that you haven’t detected. Without a reliable flow of electricity, the arc will be unstable, the heat will fluctuate, and the rod will stick.
- The workpiece is cold. The rod sticks more often when you strike the arc for the first time because both the metal and the rod are cold.
When the welding amperage is too low
First a few words about the arc, the plasma gas, and the heat.
A welding arc is a continuous electrical current passing through the gap between the rod and the workpiece.
Before you create the arc, regular air fills the gap, which is a poor electrical current conductor.
When you strike the arc, the flux evaporates and the resulting gases break down, releasing electrons.
This new gas is called plasma gas and is a great conductor for the current to pass through the gap at a steady rate.
Plasma gas gives high resistance to the current that passes through it. High resistance releases high amounts of heat that will melt the rod and the joint.
The temperature of a SMAW plasma gas is around 6500°F (3600°C), depending on the rod diameter, the flux composition, and the amperage.
This temperature is much higher than the melting point of all metals, and their alloys. For example, mild steel has a melting point of around 2700 °F (1500 °C).
If the amperage set on the welding machine is lower than necessary, there is not enough current passing through the plasma gas. As a result, the plasma gas cannot release enough heat to keep the rod’s tip and the puddle in a continuous liquid state.
Low amperage is the most common and the easiest to correct factor that causes the rod to stick.
When the arc length is too short
Now, a few words about the arc length and arc voltage.
Arc length is the distance between the rod and the base metal. It depends on the rod’s wire diameter. For a stable and productive arc, this length must be steady and no longer than the rod’s wire diameter.
Arc voltage is the voltage of the arc and depends on the rod’s wire diameter. Arc voltage is relatively low, between 17-35V.
You can indirectly change the voltage by changing the arc length. If the arc length decreases, the arc voltage decrease as well.
This is the way stick machines are designed. If the arc length changes, they keep the amperage relatively steady and fluctuate the arc voltage. For this behavior, they are called Constant Current (CC) power supplies.
Arc voltage affects the temperature of the plasma gas. The lower the voltage, the lower the temperature.
So what happens when the arc length is too short?
- When the arc length shortens, the amperage stays about the same, but the arc voltage decreases. As a result, the total amount of heat (volts*amps) drops.
- Moreover, as the arc length shortens, the plasma’s temperature drops. After a specific point, the plasma turns back to normal air. Without plasma, there is no heat, and the molten metals solidify instantly.
- If you push the rod too much and actually touch the base metal, there will be no gap for the arc and the plasma to exist at all.
The results are rods stuck to the base metal, frustration, and delays. Many call the process stick welding, not because of the rod’s shape but because it sticks so frequently.
What to do when the welding rod sticks?
When the welding rod sticks to the base metal, the first thing to do is to twist it and break it off. If that doesn’t work, release the rod from the electrode holder. Finally, you can turn off the welding machine.
When the rod sticks, and you have an older stick machine, the short circuit will overheat the rod and stress the machine. Newer inverter welding machines have components that detect when the rod sticks and drops the current.
The first thing that comes to mind is to twist the rod to release it. Sometimes it might be enough, but many times you can’t break off the rod. If you put too much effort, you will break the flux around the tip.
Another way is to release the rod by pressing the stinger’s level. This way, you can remove it without damaging the flux or bending the wire. However, there will be a momentary arc between the rod and the stinger that will scar the stinger.
You can always turn off the power supply if it is more convenient. However, do not pull the plug from the wall because the cooling fan will stop before cooling down the machine.
When a rod creates an arc, even for a few seconds, it gets very hot. If the rod sticks, it will overheat. Furthermore, the rod will stay hot for a long time after that.
For this reason, before you break the rod free, you must wait a bit and use welding gloves to remove it. Using pliers can damage the flux.
After that, you use a new rod or correct the previous one’s tip and try again.
How do you prevent a welding rod from sticking?
Now, the best part of the article is about what you can do to reduce the chances of sticking the rod.
1. Set enough amperage
Most welders try to avoid rod sticking by keeping a longer arc. But it is the lack of amperage that is responsible for this problem.
The first and most important thing is to set the amperage higher. High amperage will fix most of the rod sticking problems.
All rods have an amperage range depending on their type and wire diameter.
Depending on the workpiece’s thickness, you should set the highest amperage possible. Just a step before you will experience defects from it, such as blowing through or warping the workpiece.
When you set the amperage high enough, one of the first things to notice is that the rod does not stick to the workpiece as much when you strike the arc.
When running the bead with high amperage, correct angle, and traveling speed, the rod will not stick even if you shorten the arc length.
Your welding machine may output a lower amperage from what it indicates. If you suspect something like this, you can check it with an amp meter. Otherwise, if you don’t have an amp meter, trust your judgment and set a higher amperage.
2. Use the correct technique for starting the arc and running the bead
To strike the arc, you only need to scratch or tap the rod briefly. Then immediately lift it for a short distance. If you delay that, there will be no gap for the arc to create enough plasma gas and stabilize itself. As a result, you will have enough heat only to stick the rod.
When striking the arc with a new rod, it is at full length. Every movement your hands make will cause the rod’s tip to vibrate. Vibrations will make arc striking harder.
To reduce rod vibration, you can:
- Hold the stinger with both hands close to your body.
- Put your free hand under the main hand’s elbow.
- You could hold the electrode in the middle to stabilize it until you start the arc. Always with dry and thick welding gloves.
When you run the bead, you must focus and keep a short and steady arc length. You must have steady hands and good hand-eye coordination. These require many hours of training.
Your welding speed also matters. If it is too fast, you will move the rod past the warm puddle and into the cold workpiece, then the rod will stick.
3. Check the welding circuit’s current flow
You want to have a reliable current flow through the welding circuit to prevent rod stickiness. Most often, a poor connection of the working clamp (or ground clamp) to the base metal causes unstable current flow.
- Many new welding machines come with cheap and small working clamps that don’t provide a secure connection and cannot offer a steady current flow. Replacing the working clamp with a better one is easy and cheap.
- Connecting the clamp the right way is important too. Any dirt on the workpiece acts as insulation and will resist the desired electricity flow. Make sure you connect the working clamp to clean metal.
- Moreover, check for loose connections between the leads, the stinger, the working clamp, and the power supply.
4. Examine the quality of the welding rods
The electrodes you work with must be in good condition to prevent sticking.
- The flux may have cracks or missing parts, which drastically increase the risk to fuse the rod on the workpiece.
- Exposed flux may have absorbed moisture from the air. If you see a discolored flux, or it chips off when you handle the rods, discard them and get new ones.
- The rod might have rust on the end that connects to the stinger. Rust will affect the proper arc striking.
So make sure to use rods in acceptable condition and store the electrodes the correct way.
5. Check the welding rod’s tip before striking the arc
Before striking the arc, you must make sure that the rod’s tip is even. The wire and the flux must be at the same level. If the flux doesn’t cover the wire completely and evenly, the rod will stick like crazy.
The rod’s tip can be uneven from faulty storage, poor handling, or if you stuck the electrode and twisted it off. You must either use a new rod or correct the damaged tip.
6. Avoid rod incompatibilities with the welding machine
No matter what skills you have, if you unknowingly try to weld with a rod that your machine cannot burn, it will stick.
- Your machine might not output enough open-circuit voltage (OCV) (Wikipedia) for rods such as the E7018. OCV is the voltage between the stinger and the workpiece before you start the arc.
- Small inverter machines don’t have components strong enough to run cellulosic electrodes such as the E6010.
- If you try to use the wrong current type or polarity, the rod will stick, for instance, if you use an E6010 rod with an AC welder.
- Your machine might have a voltage reduction device (VRD) that can lead to arc striking problems.
Here is a Weldpundit article about selecting the right stick welding electrode.
7. Preheat the base metal
When you try to strike the arc on a large cold workpiece, the heat will disperse quickly, not leaving enough behind to sustain the arc.
If you preheat the workpiece where you will strike the arc, the chances to stick the rod decrease.
8. Use an inverter welding machine with anti-stick features
Modern inverter stick machines include high-tech components that detect and prevent the rod from sticking or control the side effects of stuck rods. These features are:
- Hot-start increases the amperage when striking the arc to generate more heat.
- Arc-force increases the amperage if you shorten the arc length when you run the bead.
- Anti-Stick senses when the rod sticks to the base metal and stops the current. Anti-stick prevents overheating of the rod and the power supply.
These features are beneficial if you are a beginner, but if you get used to them, it will be harder to weld without them.
There is already a guide to hot-start, arc-force, and anti-stick in stick welding if you want to learn more about them.
How to fix the tip of a stuck rod?
If you stuck the rod to the workpiece and then removed it, you will see that the flux around the tip is damaged. The flux will be uneven and leave the wire exposed. If you try to restart the arc, you will experience severe sticking problems.
Furthermore, there won’t be enough shielding gases to prevent the molten metal from reacting with the air. This will lead to defects such as porosity at the starting part of the bead.
If you want to keep and fix the rod, you can do it with various tools. For example, grind the tip with an angle grinder until you have the wire and flux at the same level. However, there is a better way to do it:
- Get some scrap metal and strike the arc on it.
- Then hold the rod with a long arc perpendicular to the workpiece for a couple of seconds.
- Long arcing will melt the wire until it is inside the flux correcting the main problem.
- Finally, you scratch the excessive flux on a file or a piece of sandpaper until the flux reaches the wire.
Correcting the tip doesn’t give perfect results, but you will start the arc easily enough.
Sticking the rod is one widespread problem with the stick welding process. The number one cause is using low amperage.
After that, not keeping a steady arc length, using flawed rods, or rods that are not compatible with your machine.
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