To cut a square hole in sheet metal you first drill a pilot hole. Next use a jigsaw with a metal cutting blade to cut around the perimeter of the square. Finally use a file or deburring tool to remove any sharp edges.
If you are going to be doing a lot of work with sheet metal then it is worth investing in a metal shearing and punching machine. This will make the job much easier and faster.
When cutting sheet metal it is important to use the proper tools and techniques. If you do not then the results can be very dangerous. Make sure that you always wear protective clothing and eye wear when working with sheet metal.
Also be sure to follow all safety instructions that come with your tools and equipment.
Get the right tools
Before you start you need to get the right tools for the job.
For this project you will need:
- A drill
- A jigsaw with a metal cutting blade
- A file or deburring tool
Let’s taker a closer look at each of these and how they are used for cutting the hole.
Drill that designed to drill metal
If you don’t already have a suitable drill for the job you need to go out and buy one. Look for a high quality drill that is specifically designed for working with metal. You don’t want a drill that is going to overheat and damage the sheet metal.
Jigsaw that can cut through metal
The jigsaw is the most important tool for this project. It is what you will use to cut around the perimeter of the square hole. Make sure that you get a jigsaw that is designed for cutting metal. These saws have special blades that are made from high carbon steel.
File or deburring tool
Once you have cut out the hole you will need to remove any sharp edges. This can be done with a file or a deburring tool. A file is the traditional way to do it but a deburring tool will save you a lot of time.
Now that you have the tools you need, let’s take a look at how to actually cut the hole.
Measure and mark the hole
Next step is to measure and mark the hole you need to cut in the metal. Use a ruler or tape measure to find the center of the hole.
Then use a pencil to mark the outline of the hole onto the metal.
Be sure to now know how to cut a square hole in sheet metal. double check your measurements before you start cutting.
It is much better to take the time to measure twice than to have to start over because you cut the hole in the wrong place.
We recommend that you use a sharpie or other permanent marker to make your lines. This will make them easier to see when you are cutting.
Now we are ready to drill the pilot hole.
Drill a pilot hole
Drilling a pilot hole in metal is just like drilling a hole in wood. You want to use a drill bit that is slightly larger than the jigsaw blade you are going to use. This will make it easier to start the cut.
To drill the pilot hole:
- Put on your safety glasses.
- Clamp the metal down so it doesn’t move while you are drilling.
- Use a center punch to make a small dent in the center of the hole. This will help keep the drill bit from slipping.
- Put the drill bit in the chuck of the drill and tighten it down.
- Drill slowly at first and then increase speed as needed. Be careful not to overheat the metal. If the metal starts to smoke, stop drilling and let it cool down.
- Drill through the metal and then remove the drill bit.
- Deburr the hole with a file or deburring tool. This will remove any sharp edges.
Now we are ready to start cutting out the hole with the jigsaw.
Cut the square hole with a jigsaw
Now it is time to cut out the hole with the jigsaw.
Start by putting on your safety glasses and gloves.
Clamp the metal down so it doesn’t move while you are cutting.
Put the blade of the jigsaw into the pilot hole and start the saw.
Cut slowly at first and then increase speed as needed. Be sure to follow your lines. If you veer off course, stop and adjust as needed.
Once you have cut all the way around the perimeter of the hole, remove the blade from the metal and unclamp it.
After cutting the hole you are left with some sharp edges. These need to be removed so they don’t cut you or catch on something.
Finish the edges of the cut hole
There are two ways to finish the edges of the hole. Let’s explore your two options. You can either use a file or deburring tool og you can sand the edges.
File or deburring tool
The traditional way to remove sharp edges is with a file. You can use a hand file or a power file. If you are using a power file, be sure to wear safety glasses.
Start by removing any big burrs with the file. then work your way around the edge, filing it until it is smooth.
If you are using a hand file, you will need to use a back and forth motion.
With a power file, you can go in circles or back and forth.
Once you have finished filing, remove any small burrs with a deburring tool. This will save you from having to go over the edge with the file again.
Sanding finish
Another way to finish the edges of the hole is by sanding them. This is a quick and easy way to remove any sharp edges.
Start by removing any big burrs with a file or deburring tool. then work your way around the edge, sanding it until it is smooth.
You can use a hand sander or a power sander. If you are using a power sander, be sure to wear safety glasses.
Start with a coarse grit sandpaper and then switch to a finer grit until you have the desired results.
Once you have finished sanding, remove any small burrs with a deburring tool.
Now that you know how to cut a square hole in metal, you can use this technique to cut holes for outlets, light fixtures, or anything else you need. Just be sure to measure twice and cut once.
Test the hole to make sure it’s the right size
Now you should be done. All that is left to do is to test the hole to make sure it is the right size.
To do this, simply put the object that will be going into the hole (like an outlet cover) and make sure it fits snugly.
If it is too big, you can always file or sand down the edges until it is the right size. And that’s it. You now know how to cut a square hole in metal.
