If you need to make a cut through a material using a circular saw while keeping the surrounding area intact, then you’ll need to learn how to make a plunge cut. This might look challenging at first, but it’s actually a fairly simple process once you get the hang of it.
While there are dedicated plunge saws designed specifically for this purpose, the average homeowner or DIYer won’t get enough use out of one of these to justify the cost. On the other hand, nearly everyone has a circular saw kicking around the garage that can be used for making plunge cuts.
Tools & Materials
- Circular saw
- Pencil
- Speed square or combination square
- Clamps
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Making a Plunge Cut with a Circular Saw – Guide
Step 1: Mark Cut Line
Before you start cutting, you’ll want to measure and mark your cut line on the surface of your workpiece. You’ll want this to be as accurate as possible, as there’s no way to make adjustments once you’ve started making the plunge cut.
Step 2: Set Blade Depth
Next up, you’ll want to set your circular saw’s blade depth so that the blade pokes out about 1/4-inch past the bottom of the workpiece.
This will help the saw work more efficiently, as well as prevent the blade from damaging anything underneath the piece you’re working on.
Step 3: Position the Saw
In order to get a perfectly straight plunge cut, it’s a good idea to draw a perpendicular line on the surface as a guide for your saw. You’re going to line up the tip of your saw with this line and use it as a pivot point for rotating the saw blade into the workpiece. Use a speed square to mark this line.
Now, position the saw so the front tip is touching your perpendicular line and the rest of it is suspended above the workpiece. Now, slide back the saw’s blade guard and hold it in place so it can’t slide forward while you make the plunge cut.
Step 4: Make the Plunge Cut
The goal here is to pivot the saw on its front tip until the blade has cut all the way through the material.
Grip the saw with both hands, turn on the trigger and slowly plunge the blade into the work surface until the shoe is flat on the surface. At this point, the blade is all the way through the material and the plunge portion of the cut is complete.
Step 5: Continue the Cut
Once the plunge cut is complete, you can continue cutting for as long as you need to.
Plunge cuts are often used for building cabinets, sinks, trimming doors, and other jobs where you need to make a cut inside a material while keeping the edges intact.
They can be used to make square or rectangular holes, but you want to be careful when cutting out the corners. Use a hand saw to finish off these corners rather than trying to complete them with your circular saw.
