Whether you are a professional welder or a metal-working hobbyist, you have likely seen sparks fly -literally! Anytime small fragments of metal are broken off from the surface, they heat up and ignite due to friction. The sparks that result are the little pieces of metal burning when they encounter oxygen in the air.
The sparks that result from cutting or grinding metal can be dangerous. Not only can they burn the eyes and/or skin, but they also can also ignite combustible or flammable materials in the area, causing a fire. Therefore, it is imperative that you always take the proper precautions when welding or doing any kind of metalwork.
Now that you know sparks from cutting metal can indeed start a fire, let us explore this topic in more detail below. I will discuss how and why this happens, which metals are the most ‘spark worthy’, and what safety measures you can take to prevent an accident. I will also discuss whether (or not) an angle grinder can start a fire, how hot (temperature-wise) metal sparks can get, and if aluminum can produce sparks when cut.
So, if you are ready to learn more about cutting metal and how to prevent sparks from starting a fire, then please read onward…
Can Metal Sparks Cause a Fire?
Most welding fires are caused by sparks or when droplets of melted metal land on flammable materials.
As well, when combustible gases or vapors in the air are ignited through heat, this too can cause a fire.
Molten metal sparks, for example, are caused by the heating process of iron or steel typically referred to as arc welding.
Arc welding is a process by which pieces of metal are joined using electricity. The applied electrical current produces sufficient heat to melt the metal.
When the melted metals cools, the pieces bind themselves together at the melting point.
This process often creates a ‘spray of sparks’ that can be dangerous and cause a fire should they land on anything flammable, such as wood, paper, or fabric.
How to Cut Metal Without Sparks?
The best way to cut iron or steel without sparks is to use a hacksaw rather than an angle grinder.
Attaching a carbide grinding bit to a rotary tool such as a Dremel, for example, limits the amount of sparking and helps remove any small pieces of metal your grinder may miss or cannot reach.
If you want no sparks at all, then consider cutting a different type of metal such as aluminum.
Another option is to put duct tape on the iron or steel. This works to reduce the amount of friction caused by using an abrasive tool on a metal surface.
Less friction means less sparking. Simply wrap some duct tape around the metal two or three times to create a padded surface.
Using a pencil, draw a ‘cut line’ on the tape (to ensure the proper length) and then cut. It is that easy!
Can an Angle Grinder Cause a Fire?
Cutting metal with an angle grinder causes a lot of sparks. However, the sparks that result are not that serious of a fire hazard.
The reason being that the sparks emitted (generally) do not get hot enough to ignite. Therefore, the chances of an accidental fire occurring are quite low.
The only way a fire could start is if the sparks happen to fall continuously on the same spot of highly flammable material.
How Hot are Metal Sparks from an Angle Grinder?
While metal sparks have the potential of reaching 2,000 degrees Fahrenheit (or 1100 degrees Celsius), those produced when using an angle grinder have a small mass, not enough to cause a fire, in most cases.
That does not mean, however, that is not possible. Proper safety measures should always be taken when using a power tool to cut or grind metal.
For more information, please see below under the subheading entitled: What Safety Precautions Should be Taken when Cutting Metal?
Does Cutting Aluminum Produce Sparks?
Anytime metal is struck or cut, it will spark because of friction. Aluminum does not spark near as much as is iron or steel, however.
It is a softer, lighter metal which produces less heat and friction when cut. As a result, it sparks less and therefore is less likely to start a fire.
What Metal Makes the Most Sparks?
The two types of metal that spark the most are iron and titanium. The surface area of iron is larger than its volume and a result will heat up very quickly and spark easily.
These sparks glow bright red and can start a fire if they land on any flammable material.
Titanium, on the other hand, is a non-ferrous metal and gives off a ‘shower of sparks’ when cut. These sparks are very tiny and burn white-hot.
They can ‘fly’ about easily and ignite on any nearby combustible material, thus causing a fire.
What Safety Precautions Should You Take when Cutting Metal?
Anytime you work with metal, the most important thing is to do is try and avoid injury.
When cutting or grinding metal (or any job requiring you to use a power tool and/or heat up metal), be sure to follow these important safety measures:
- begin by inspecting all tools carefully to ensure they are in good condition
- always wear safety gloves, especially if you are a beginner
- always wear safety glasses or goggles, preferable ones that are CSA-certified with side shields
- always wear earplugs when working with loud power tools, such as an angle grinder
- be sure to use a well-mounted vice to hold your metal pieces securely while working on them
- never grasp hot metal tightly – instead, use a light grip to prevent nicks and cuts
- never, ever run your bare fingers across the raw edge of the metal
- anytime you use a tin snip, be sure to keep it moving deep along the cut line – avoid making short cuts with the edges of the tool as this will create jagged edges
- do not sweep scrap pieces of metal into the trash with your hands – use a brush or vacuum instead and be sure to wait until the pieces have cooled completely before discarding
- always work in a well-ventilated area with adequate lighting
- make sure the work area is free of combustible materials
- if possible, invest in good-quality tools and never use tools that are damaged
Should the unthinkable happen and a metal fire breaks out in your workshop, never try to put it out using a CO2 fire extinguisher or water? Pouring water over a metal fire causes the heated particles to separate into hydrogen and hydroxide.
Hydrogen acts as an accelerant by increasing the rate of combustion which can cause an explosion. The correct way to put it out is to use a powder extinguisher instead. These can be found at your local hardware store or online at Amazon.com.
A good one to invest in is the Amerx B402 ABC Multi-Purpose Powder Fire Extinguisher. At 5 pounds, it comes with its own wall bracket and is easy to maintain and service. The steel cylinder and all-metal valves make it a rugged, dependable extinguisher that is both convenient and economical. Go online and check it out today!
The sparks that result from cutting or grinding metal can be dangerous.
Not only can they burn the eyes and skin, but they also can also ignite flammable materials such as wood, paper, or fabric causing a fire.
Therefore, it is imperative that you always take the proper safety precautions when cutting or welding metal.
I hope you have found this article to be both interesting and informative. Thanks for reading and always remember – safety first when it comes to working with metal. Good luck!
Cheers, tools owners!