Picture this: You want to drill some ⅛ “holes in your stainless steel project. You tap your punch, line up your drill and squeeze the trigger…
But the bit spins helplessly on the steel barely making a dent and billowing smoke.
If this sounds familiar, let me share the right way to cut stainless steel.
How To Cut Stainless Steel:
To cut or drill stainless steel without wearing down your drill bits or blade you’ll need three things: a variable speed drill (or saw), a squeeze bottle and water. You’ll want to keep your drill bit or blade cool spraying water from your squeeze bottle on the bit and maintain a slow cutting speed.
So, let’s get down to business.
When you want to cut stainless steel (like most metals) you’ll want to first secure it in the proper manner. For small pieces of metal, a vice will work well to secure your metal so you can cut or drill it.
Once you have that you’ll need a squirt bottle filled with water.
Now, once you have all your material in place you’re ready to start.
Grab your stainless steel and use a scribe to mark your line to cut. If you’re drilling a hole using a center punch to get a dimple started or simply use your drill at a slow speed to get a hole started
Once you have your line marked or hole started you’re ready to actually cut.
If you are drilling set your drill into the divot and slowly squeeze the trigger forward.
You want to “feel” the bit cutting into the metal.
A good sign is to watch the bit slowly cutting into the metal and creating small shavings around your hole
I can’t give you a specific speed to use when drilling because there are so many different variables (steel thickness, drill diameter size, etc) But, if you want a good resource that gives you a formula, check this site out.
But remember, if you see shavings coming off, you’re probably going to right speed.
By the way, since we are talking about drills, check out this comparison between Ridgid and Dewalt cordless drills. Oh, and here is a chart I use all the time to reference drill bits that’s super helpful for me.
When cutting stainless steel it’s best to use a cold band saw but you can also use a jigsaw in the field for smaller cuts and thinner materials ( like 1/16” ⅛” etc.) If you are cutting thin materials make sure you secure your work piece in a vice or to a workbench with a set of clamps
The most important thing is to have your squirt bottle ready when you’re going to cut your stainless steel. Notice how the bottle is positioned right next to the cutting blade and is being squeezed repeatedly.
Remember the two key ideas: low speed and a cool bit. By continuously spraying water on the cutting blade you’re keeping the bit cool and the cutting action consistent.
And that’s how you cut or drill stainless steel easily.
Also, remember to use hearing protection as showing in the video. Loud saws and drills can affect your hearing over time – so check out this article for some good hearing protection. And here is the hearing protection I use every day.
But that’s not all….
Common questions when cutting stainless steel
Q: Do I need an expensive drill bit like cobalt or HSS to drill stainless steel?
A: Although having a harder bit will help make the process easier, it’s not necessary at all! The secret is a slow speed and keeping your bit and work piece cool with fluid. Simple, cheap bits will do the job if they are kept sharp.
Q: Do I need to use water as my cutting lubricant?
A: No, you can use other lubricants like rapid tap or tap magic. The issue with these fluids is the application. When using this with common mild steel you place a small amount in your dimple and then drill – the result is great. When drilling or cutting stainless you need a lot of lubricants to keep your bit cool. With tap magic being about $100 a gallon you can see how expensive this can be. Water is cheap and effective.
Q: Do I need to drill a pilot hole when working with stainless steel?
A: It depends. When you’re making a larger hole, say ½” or more it’s best to have a pilot hole. With smaller holes, say up to ¼” or so, a simple tap with a center punch will be good.
Q: Why is stainless steel so hard to cut?
A: Stainless steel contains chromium, which makes it much harder than mild stainless steel. You want to reduce the friction and thus the heat. The hardness of the steel makes the friction between the bit and the metal result in heat. Heat wears out bits and blades.
Q: I am drilling through thin stainless steel and my hole is not round, what can I do?
A: If you are drilling through a thin piece of metal and your hole is not round, you have a problem Your drill bit has two sides or flutes. While drilling one side is not supported properly, so the bit wavers. You can use an old piece of cloth to provide stability and give you a nice round hole.
See this old machinist trick on youtube
Q : Do I have to cut stainless with a band or chop saw? Is there an easier way?
A : Yes, in fact I only drill stainless when I forget my plasma cutter. A plasma cutter skips all the guess work and makes cutting stainless super easy. I highly recommend you buy one, and here is a review of the hypertherm plasma cutter if you want to get familiar with a good machine.
Cutting or drilling stainless steel does not have to be a frustrating process. If you use a slow speed, a cheap squirt bottle and some plain water you can avoid the frustration of burning out expensive blades and bits. We covered step by step how to drill or cut any size stainless steel to help you be successful in the shop or on your home project!