Many people wonder can a circular saw cut metal? The answer is: it depends. In the metal cutting vs. circular saw problem, you need to consider many factors, such as the speed of the saw blade, the blade itself, and the shavings produced by the saw blade. You may be looking at your circular saw and wondering, "Why buy a metal saw when a frame saw does the same job?"
It's a fair question, actually, you can do it. Many manufacturers make 7-1/4" metal cutting blades that fit standard circular saws. However, even the best circular saws can fall short when you start comparing features tailored specifically for metal cutting applications.
A closer look at metal-cutting circular saws may give us insight into why Milwaukee, Makita, and others created specialized tools for cutting metal.
Quick Article Summary
Metal chop saws differ from standard circular saws in the following ways:
- Reduce RPM to cut metal more efficiently
- Optional chip collector to collect metal shavings (some models)
- Smaller blade size further reduces RPM and allows for more control
- Closed housing for better debris control
The Milwaukee M18 Fuel 7-1/4" Circular Saw spins at 5,800 idle, while the Milwaukee FUEL 8" Metal Saw spins at 4,000. That's even higher than the 3,900 RPM of their smaller models. Similar speeds are available in the models.The blade speed of a wood cutting frame saw far exceeds the recommended cutting speed for metal carbide saw teeth.
But that's not all, because you also want to watch the size of the blade. Not only do metal chop saws spin at a lower RPM, but they sometimes use smaller blades. When they do, the teeth spin at significantly slower speeds than a circular saw with a higher rpm and larger blade. Check out our router bit speed article that covers similar issues for woodworking.
Standard metal cutting circular saw blades are usually of the 5-3/8 inch blade size. However, as mentioned above, Milwaukee makes a 7.5" saw. This is important because it allows a maximum cutting capacity of 2-9/16 inches. The smaller saw is almost 1-1/2 inches shorter than a standard size 7-1/4 inch frame saw blade and cannot cut 2 inches of conduit at a time.
The devil is in the (design) details
Cutting metal is harder than cutting wood. Metal cutting is more like abrasion than chipping away large grains of material. The 7-1/4" blade creates a lot of sparks when cutting metal at high speeds. It's the equivalent of flying, burning shards of hot metal that wear down the blade very quickly.
Metal chop saws are designed so that they collect or deflect these splinters better than frame circular saws. Last, but more generally, the open housing of conventional wood-cutting circular saws may not prevent metal debris from building up. For this reason, metal cutting saws usually have a closed housing.
Safety Tip: Always verify that the blade RPM rating is within the saw's RPM rating. This also applies to metal cutting saws.
As we mentioned earlier in this article, metal cutting saws are specialized in their task. With modern battery pack technology, they can make dozens of cuts—even through tough materials like stainless steel. This means that modern cordless metal cutting saws can now do jobs that were previously only possible with corded tools.
We like it because it eliminates both a tripping hazard and a common problem of accidentally cutting the cord. If you need to save money and plan to do a lot of cutting, we recommend a wire saw. Wire saws also save weight because they don't require a battery pack.
For portability and flexibility, cordless metal cutting saws reign supreme and offer plenty of power and run time.
the bottom line
So why use a metal cutting circular saw instead of a regular one?
- Enclosed Motor Housing
- Hot chip ejection/collection/deflection
- Proper (lower) blade speed
It is not a good idea to use a wood cutting saw for metal cutting. Stick to a circular saw designed for each specific task, and don't be afraid to opt for a corded metal cutting saw if a cordless model is too demanding for your budget. You definitely don't want to burn out your circular saw and leave yourself without the tool to get the job done. Like many others, it was an expensive lesson.
Shop for Metal Saws at Acme Tools