When people think about welding they often envisage sparks and spatter flying in the air as the hot torch is applied to the metal. This is visually entertaining, but in reality, welding spatter is a real problem because it increases the need for cleaning and it wastes a lot of material. If the proper safety equipment is not used there is a risk of severe burns. Reducing spatter should be a priority for all new and experienced welders.
What is Welding Spatter?
Weld spatter is comprised of balls of molten metal that fly out from the weld pool and adhere to anything in the near vicinity. That could be what you’re welding, your welding tools, or even yourself. These balls of metal are extremely hot, they stick in place firmly, and they tend to make a sloppy mess that degrades the weld quality.
If the spatter lands on you and you’re not wearing protective gear, your skin can be scorched and burned. Clogs of spatter can cool on gas ports and tools, which causes problems with your welding gear. A certain amount of metal was expelled from the welding pool as spatter and this removal of metal may have degraded the integrity of the weld.
8 Causes of Spatter in Welding
So, what is the cause of the spatter in welding? There are eight main causes to understand, and we will present some solutions to reduce the chance of spatter:
Cause #1 The Metal Composition
This may seem strange, but the metal quality can have a significant impact on the volume of spatter produced during welding. Certain metals are not ideal for welding and they may have components added to them that vary the strength and degrade the weld-ability. Some metals are manufactured inexpensively, and these often contain cheap additives that contain contaminants that create excessive welding spatter.
Always choose the right metal for welding for the project and if you must use poor-quality metal, take appropriate precautions.
Cause #2 Dirty Metal
Now that you’re aware of the poor quality components that can be in the metal, it’s important to understand that dirty metal can contribute to weld spatter too. Surface contaminants, such as oil, marker lines, grease, dust, dirt, corrosion, and others, can increase welding spatter.
Always clean the metal before welding. In many cases, a wipe with a clean rag will suffice, and corrosion can be removed with sandpaper or a grinder.
Cause #3 The Metal Coating
Sometimes, you may have good-quality metal to weld, but the coating may cause excessive weld spatter. This may be a galvanized coating or another material, such as chrome, rubber, paint, zinc, or something else. To create clean welds it’s important to use purer metals and this, in turn, will reduce spatter. Certain coatings like pre-primed steel are designed to contain any weld contaminants, and they reduce spatter.
Always grind off coatings where you plan to weld to make the surface pure, and this will reduce spatter. If you don’t grind the immediate surrounding area, the heat will consume that material, and you will get spatter.
Cause #4 Low-Grade Filler Material
Using a high-quality filler can be expensive, but it will reduce spatter, and you’ll have the right composition for clean welds. Again, corporations manufacture cheap fillers with components that are contaminated, and this causes excessive spatter.
If you buy cheap filler more welding spatter is created and the time and effort needed to clean up the weld make any “savings” irrelevant. When you choose a filler, research the various types and choose a quality product designed to reduce spatter.
Cause #5 Contaminated Filler Material
If you’re a welder that leaves their equipment and materials uncovered when they’re not in use, it’s time to stop. Contamination with dirt, dust, oil, rust and other materials will cause spatter.
Cover all consumables and wipe down stainless steel filler rods before you start welding. If you grind steel, clean it up because it can cause stainless steel rod corrosion. Most MIG welding spools are covered, but the wire should be stored in a bag unless you’re using it on a daily basis or the spool cover is sealed.
A buildup of moisture on the coil can lead to rusting if the coil is left open for too long. Arc welding rods are less prone to contamination because the flux on the rod surface offers some protection. But, if the welding rod is coated with oil or it’s wet, there will be more welding spatter.
Cause #6 The Welder Settings
If the welder settings are wrong, there is an increased risk of spatter, and this is especially true if the amperage is too high.
Select a lower amperage by increasing the voltage or decreasing the wire speed. Consider adjusting the Electric Stick Out (ESO), which is the distance from the contact tip to the workpiece. If the ESO is too high, there will be a lack of penetration, porosity, and the volume of the spatter is increased. The best way to check the welder settings is to practice on a clean piece of scrap metal and make adjustments as required.
Cause #7 Welding Gas
The gas that you use will have an effect on clean welding. Carbon dioxide is a less expensive welding gas, it can help with deep penetration, and it shields well, but it creates more weld spatter. Argon is used for TIG (stainless steel) and MIG (aluminum) welding, but welding steel with Argon creates low-quality welds and excessive spatter.
There are various mixtures of welding gas that are designed for specific welding tasks. As an example: welding thicker steel requires a gas with a higher percentage of carbon dioxide to improve the quality and reduce spatter. Always choose the right gas mix for the metal thickness, and the weld will be cleaner and smoother.
Cause #8 Welding Technique
The welding speed and angle with either the push or drag technique can affect the spatter. Using a steep angle can create a lot of spatter and this is especially true with certain arc welding techniques if the drag is too fast. If the wire feeder cannot operate at a steady speed, this will cause an amperage fluctuation, and this increases the spatter.
The optimal welding angle is 15º with correct travel speed and optimal wire feeding. Don’t go too slow or too fast, and if you have to deviate from the 15º angle, prepare for some weld spatter.
How Do You Prevent Spatter In Welding
The specific solutions shown above will minimize spatter, but steel and stainless steel spatter is hard to remove. Let’s take a look at two general solutions that can prevent ugly weld spatter and save you some valuable time.
1. Welding Tape
This is usually aluminum tape that you can apply to surfaces where you want to prevent the accumulation of spatter. It’s an expensive option, but for certain critical parts like machined surfaces and parts that cannot be damaged, it’s an ideal solution. There are tapes made from lower-grade materials, but these can melt or even burn when they are exposed to spatter, which makes them useless.
This is an oil-based spray that is applied over the entire welding area. You can weld over this spray with no adverse effects on the weld quality, and the spatter cannot stick to the metal. This leaves loose balls of metal on the project that can be brushed or chipped away easily. This is not a perfect product, some spatter can still be melted on the workpiece, but it will reduce the spatter significantly.
How Do You Remove Spatter After Welding
There are two tried and tested ways to remove spatter after welding:
1. The Grinder
This can grind away spatter down to a clean finish, and it’s the fastest way to get rid of excessive weld spatter. In many cases, a light tickle with the grinder will be sufficient to clean the weld or joint.
2. Spatter Chisel/Hammer
A few isolated spots of weld spatter can be removed with a spatter chisel/hammer. This tool has a cold chisel head and a spring inside the handle to chip away spatter. This approach is quick and easy and there is usually little to no evidence of spatter left behind.
How To Remove Weld Spatter From A Welding Helmet
Move the lens of a buffing wheel around the welding helmet, and the spatter should be removed in a couple of minutes. Continue with sufficient pressure until any remaining scratches are buffed out. At some point, an older welding helmet will have deeper scratches that cannot be fully buffed out, and at this point, it’s time to consider a replacement.
FAQ’s-What is Welding Spatter
What causes too much spatter with a MIG welder?
Contaminants, such as dirt, dust, oil, grease, and marker pen lines are the most common cause of molten metal weld spatter during MIG welding.
Does weld spatter stick to cast iron?
No, cast iron is great for welding because the surface will stay flat, and the welding spatter cannot stick to it.
Does the weld spatter stick to aluminum?
Steel weld will not stick to aluminum.
Does stainless steel resist weld spatter?
Yes, unless the welded joint is drastically overheated.
Is it Bad to have welding spatter?
A small volume of weld spatter isn’t too bad, but too much is a real problem. The clean-up times are longer, and a considerable amount of material is wasted. Also, weld spatter can burn your skin, and it’s important to take appropriate safety precautions.
Conclusion–What is Welding Spatter
Welding spatter is an ever-present hazard for welders, and there are several different causes. Weld spatter can be dangerous, and it can degrade the weld quality and waste materials. So, it’s a good idea to reduce the spatter using the solutions presented in this article. Reducing spatter will improve safety, productivity, and efficiency and keep your welding equipment safe. Adjusting your welding technique and checking the welder settings is important to ensure that you can weld to a high standard and reduce spatter.