Jigsaw 101: How To Make a Plunge Cut

We’re continuing our Jigsaw 101 series by talking about one of a jigsaw’s lesser-known capabilities: the plunge cut. This technique lets you cut from the middle of a board without pre-drilling holes. While they might initially seem intimidating, plunge cuts can make you more efficient in the workshop and expand your project capabilities. 

This Old House contributor and MyFixitUpLife host, Mark Clement, explains what plunge cuts are and how to make them safely.

When To Use Plunge Cuts

Plunge cuts come in handy for both woodworking and home improvement projects. A few common scenarios where you might use them include the following:

• Cutting access panels in walls and ceilings
• Cutting speaker openings for living room and den cabinets
• Installing recessed light fixtures
• Making holes for electrical outlets in drywall or paneling
• Making sink cutouts in countertops
• Building a beanbag-toss or cornhole board

Safety Considerations for Jigsaws

Safety is always first when you make a plunge cut. Put on safety glasses and hearing protection, and clear your work area of any obstacles. You should also clamp the material down to a workbench or set of sawhorses so it won’t move as you cut.

Preparing For a Plunge Cut

The right blade, markings, and workspace make all the difference for a clean plunge cut.

Selecting the Right Blade

Choose a blade appropriate for the material you’re cutting. If you’re working with wood, a general-purpose blade with 10–12 teeth per inch (TPI) is a reliable choice. For clean cuts in thinner materials, look for a blade with more TPI. Keep the blade sharp and in good condition to minimize tear-out and get smoother cuts.

Marking Your Cut Line

Use a pencil or marking tool to mark your cut line clearly. If you’re making interior cutouts for electrical outlets or recessed lights, you’ll want to draw the entire shape you plan to cut.

Making the Plunge Cut

Once you’ve checked your marks, it’s time to get your jigsaw to work. Set the cut depth for the board you’re working with to avoid wearing out the blade. 

Position the saw near your starting point and tilt it forward so the front edge of the shoe rests on the material. At this point, the blade still isn’t touching the workpiece.

Then, start the saw slowly, gradually lowering the blade into the material. Once it’s through, level the saw and keep cutting slow and steady along your marked line. 

Once you’ve followed your line back to the starting point, you only need to make relief cuts for your sharp corners.

More Tips for Clean, Accurate Plunge Cuts

Keep these other tips in mind for the best results with your plunge cuts:

• Start the plunge cut slightly inside your marked line. This is to account for the blade’s width.
• When initiating the plunge cut, use a slow-speed setting to stay in control of the tool.
• Let the blade reach cutting speed before you start the cut.
• Apply steady, even pressure throughout the cut so the blade doesn’t wander. However, you should still let the blade do the work for you to avoid binding and bending.
• When you arrive at a corner in your shape, slow down and make gentle turns. You don’t want to overcut by going too fast through the material, and you also don’t want to bind the blade by attempting to turn the saw too sharply.
• Make a rough cut for cleaner edges first, then follow up with a finishing cut along the line.

Troubleshooting Common Plunge Cut Issues

Even experienced woodworkers can encounter challenges when making plunge cuts. Here are a few common problems and solutions:

Blade Binding

Binding is when the blade catches on the material so it can’t oscillate back and forth. It can happen if you try to cut too quickly, turn too sharply, or use a dull blade. If the blade binds while you’re cutting, stop the saw immediately to avoid damaging the workpiece, breaking the tool, or injuring yourself. 

To prevent binding, use a sharp blade that’s appropriate for your material, and keep a steady, moderate piece when cutting. Keep the material properly supported, as it can also bind the blade by moving around on its own.

Splintering and Tear-Out

Splintering and tear-out can happen when you plunge cut through plywood or laminated materials. Use a fine-toothed blade and apply masking tape on both sides along your cut line to minimize it.

Plywood tends to have a “good side” and a “bad side” based on imperfections, roughness, and knotting. You can lower the chance of splintering by cutting with the plywood’s better-rated side facing down.

Inaccurate Cuts

If you’re struggling to follow your cut line accurately, take your time and resist the temptation to follow the blade. For straight cuts, you can use a guide to help you drive the saw forward. If you’re cutting a curved design or enclosed shape, you’ll want to make relief cuts in tight corners.

Jigsaws with orbital settings may also help you make better plunge cuts. The orbital action moves the blade slightly forward on the upstroke, improving your cutting efficiency and reducing tear-out. You can adjust the strength of the action based on what material you’re using and the finish you need.

Maintaining Your Jigsaw

Once you’re done making your plunge cut, unplug your jigsaw or remove its battery pack. Wipe down dust and debris with either compressed air or a brush. Disconnect the blade and wipe it and the shoe down with a clean cloth.

While you’re cleaning, check to see if the blade needs replacement. If you’re noticing it takes more effort to make cuts, if the cuts have rough or splintered edges, or if the material is visibly burning or scorching, then it’s time to replace the blade.