Welding Spatter Explained [Molten Metal Drops]

Last Updated on May 2022


Every welder will tell you one of the biggest challenges faced in the process of welding is spatter. If you are a beginner, you might not be sure what this is and why it’s such a nuisance. Most importantly, what causes it and are there ways that you can use to reduce spatter?

What is spatter?

What draws your attention to a welder doing his job? First, there is the noise coming from the cutting then there are those sparks that fly in almost all directions as the welding machine tackles the metal. The sparks are tiny balls of molten metal that are spat from the weld to your job and sadly to your body. These tiny bits of molten metal are referred to as spatter.

The problem with spatter is that it can cause painful damage on your skin if (and it usually does) penetrates your clothing and gets to your skin if you are bot wearing a clothing such as OSHA recommended welding sleeves. Spatters sticks on the surface you are working on. and leaves an unsightly mess behind. All of these are unwanted outcomes. So what causes spatter and how can you reduce it?

What causes spatter?

There are several reasons for this nightmare. The most notable are:

  • The quality of welding material.
  • Quality of weldable filler
  • Welder settings
  • Welding technique used
  • The welding gas

Let’s delve further and see how each of these causes lead to spatter before we look at how to reduce this nuisance.

  1. Quality of the welding material

Armature welders might mistakenly think all welding material is the same. That’s not true. The quality of the material you weld is a major determinant of the magnitude of spatter produced as you weld.

Quality in this context includes the composition of the material, how clean it is and the quality of the material used to coal it. Let’s break this down.

i) Composition of the weld material

Not all metals are made for welding. Some of the materials have some additional components that are not welding-friendly. You might also find some inexpensive material sold as weld material while in the real sense it is not. Instead such material contains some cheap additives added in the core manufacturing process. These impurities and outright wrong material is a leading cause of spatter.

How do you reduce spatter caused by this reason?

Do not use this kind of material. Instead, get new metal material that will yield as little spatter as possible. What happens if these are the only materials you have to complete the job? Read on and get the tips given in the “other solutions” section to help you minimize this menace.

ii) Quality of metal coating

You might be having the right metal, but you still generate a lot of spatter. The problem could be the coating material used to line the metal. Galvanized coatings, chrome, rubber, zinc and any other coating will surely lead to spatter.

The more you can avoid coated metal the better for you. Unfortunately, this is not always the case. But note that pre-primed steel is designed without these contaminants and hence will not add the problem of spatter to your welding.


Use a grinder to get rid of the offending coating. Doing so before you weld leaves a pure surface that will produce much less spatter. To be on the safe side and achieve better results grind at least three quarters (¾) of an inch around the surface you are welding.

iii) Dirty metal

Other than the coating, any other impurities on the surface of the weld metal will cause spatter. It doesn’t matter whether the offending substance is grease, il, dust or marker pen lines as long as it’s on the weld material it’ll cause spatter.


A dirty weld is a problem. So, ensure your weld is clean before you start to work on it. This does need an elaborate cleaning process; a quick wipe using a clean rug will do the trick and save you a lot of agony with spatter.

You’ve ensured the quality of the material is well-taken care of but that does not guarantee you won’t get spatter as you weld. You need to look at the next component.

  1. Issues with the Weldable Filler

This is the joining material placed at the point you are welding. It helps connect the weld. If you compromise on the quality of this filler, spatter issues will still rear their ugly face.

Several filler issues can lead to spatter. These include:

i) Poor grade filler

As long as you use low-quality filler you are not yet out of the woods. Be keen when shopping around for your weldable filler. Some manufacturers of these consumables produce low-cost fillers. Many of these filers have added components that have no relationship to welding.

Though such fillers will serve the purpose, they will generate extra spatter as a result of the additional components.


Ensure the weldable filler you use comes from a reputable brand and has the right composition to yield clean welds. Never mind that the superior fillers will cost you more but it’s worth the cost.

Contaminated filler

The problem with your filler might not be the manufacturer. In fact, the problem is not even with the original quality of the filler. You might be a problem.

If you leave your filler without its cover, the filler will get contaminated with dirt, oil, dust, and other environmental contaminants. All these unwanted guests will attach to the weld and give you a rude shock.


Keep you filler and other consumables covered every time they are not in use. This will prevent the contaminants from attaching to the filler. One filler that might not worry you so much is stainless steel rods. These fillers don’t rust. However, if you keep let them stay out for some time, then you need to wipe them before using them to weld.

Steel dust, though from steel, can cause your stainless steel rods to rust and contaminate your welds. This contamination will affect the performance of your welding machine and lead to the production of spatter. To avoid this it’s advisable to keep your rods away when you’re grinding steel.

You’ve taken care of the weld material and filler issues but can you now weld happily without getting spatter from your job? Not yet. There’s still more to consider.

  1. Welder Setting

MIG welders

Welders have settings that are used to regulate how the machine works. Looking at the user manuals for MIG welders, you’ll notice recommendations for wire speed, gas flow rate, and power settings.

A common cause of spatter as far as settings are concerned is the irregularity with the machine’s wire feed or excessive speed. If the filler wire makes its way to the weld pool spatter becomes inevitable. Why?

The extreme heat melts the solid wire and in the process, the filler wire liquefies and creates a pool. If the steel is rather cold, it will affect how the wire responds to the heat. When the wire touches the pool before it melting and splashing it, it causes a pop and generates spatter.

This means for you to minimize splatter the welder setting has to be sufficiently hot to melt the wire before hitting the pool at the right place.

SWAW settings

The settings of the Shielded Metal Arc Welding (SMAG) have to be adjusted correctly. The heat has to be just right for the rods and the metal thickness. If the wielding is too cold, it will lead to inconsistent welding. In this case, it will be something between sticking and welding. This will, in turn, cause excessive spatter, a terrible weld, not to mention a frustrating process.

Speed settings are a critical issue you should consider. Set the speed correctly so that it’s just sufficient to reduce the spray of spatter


Get some clean scrap metal and practice as you adjust the MIG and SMG settings to a level they don’t add to the spatter you get. Remember, the manufacturer’s recommendations might not always reduce spatter in this case so trust your trial and error method to arrive at the most convenient settings for your project.

  1. Your Welding technique

So even after getting all other things right you still have a personal role to play? Most people think welding is just pointing the welder to the metal and there you have it. That’s not the case. How you weld can make a difference whether you get full-blown spattering or get minimal to near zero spatter. Knowing and using the right welding techniques is critical if you have to contend and deal with spatter. Let’s highlight two categories of techniques that can help you achieve your minimal-spatter objectives.

i) MIG techniques

Go firing at your metal using a MIG torch inclined at an angle of 20 degrees and tell me you don’t get a super-spray of spatter. In short, you have to get the angle right. Doing so not only changes the penetrations of your weld, but it also determines the magnitude of spatter you generate.

So, what’s the best angle? There are no hard and fast rules here but angles that are steeper than 15 degrees will increasingly deliver more spatter. You can imagine what amount of spatter you can get with a 5-degree angle.

Other than consistency in wire speed two other factors determine the amount of spatter you produce. These are a steady hand and the aped of travel of the gas. If you want to reduce spatter, find the right speed, the angle, and line and be consistent with it.

ii) SWAW techniques

SWAW welding demands fewer techniques to achieve fewer spatters. Pushing, for instance, will create fewer spatters than pushing. So know when to push and do it. Always use the correct travel speed and stick to the best speed that produces minimal spatter.

  1. Welding gas

Is every welding gas the same? Not quite. There are different gases that you can use to weld. All do what they are supposed to do, but the results differ. Some commonly used welding gases are pure argon, pure CO2 and a mix of Argon and CO2.

So, what’s the difference and how does it impact spatter?

Pure Argon

This gas is basically used to MIG-weld aluminum and TIG welding stainless steel. This welding gas is known to produce quite some spatter. If you use this gas and notice some spatter the problem might not be all those causes listed above. This might be the culprit.

Pure CO2

This gas is quite popular thanks to its relatively low cost. The gas facilities deep penetration and shields pretty well. The only downside is that it produces much more spatter than pure argon. So, again if you hold all the other factors constant and you still see a spatter, the CO2 might be the cause.

  1. Argon and CO2 mix

This hybrid gas comes in different mixes with each mix being best for specific kinds of MIG welding. As a rule of thumb the thicker the steel the higher the ratio of CO2 in the gas used to weld the metal.

The methods highlighted above will certainly help you reduce splatter if used appropriately. However, these are not the only techniques you can use. When used with other equally powerful methods, you can further bring down the amount of spatter. Consider the following.

Use Welding Machines with special features

Advances in weld machine technology have seen the rise of welding machines with features that minimize or virtually eliminate spatter. Ultra-high-speed electronics has it made possible to develop welding power sources that focus on spatter reduction.

Welding Spatter Explained

Other Methods to fix the spatter problem

i) Use a welding tape

Generally, this is a tape made from aluminum. Apply the tape on any surface that you want to keep the spatter away from. Do not apply the tape on the exact surface you want to weld. The good thing about this tape is that it prevents spatter from melting into parts of the surface you are welding.

The downside of this method is that the tape can be pricey, but that depends on where you buy it. If you low on budget you can still use other tapes but take care since most materials can easily melt or catch fire when exposed to spatter.

ii) Use an anti-spatter

If you want to prevent spatter from sticking on the surface, this product offers you a good solution. An anti-spatter is an oil-based spray which you spray over the area you want to weld.

The good thing about it is that you can weld over it without affecting the quality of the weld. You can then easily chip it away or brush it off. But don’t be too sure that some spatter will not melt into your work surface.

iii) Grinder

If you want to grind away any residue on your weld, an angel grinder with a flapper wheel will do the job. You can [read our full guide] on the top rated angel grinders for spatter related jobs.

iv) Spatter Chisel

When you still have some ugly spots that you want to get rid of, a spatter chisel proves to be a trusted friend. Use the cold chisel head to easily chip away whatever spatter is left on your workpiece and leave the surface smooth and looking good.


Though spatter is the most challenging problem you might on the job, it is still possible to fix spatter problems and enjoy your welding assignments. Apply all the seven strategies to all your upcoming welding projects and you will be sure to enjoy this otherwise great craft in your entire working life.

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