Plywood is a hugely versatile material that is used for a wide variety of projects. Cutting plywood with a circular saw is one of the easiest ways to get a smooth, professional look for your project.
Plywood splinters and chips relatively easily and can leave you with a poorly finished product if you don’t know what you’re doing, however.
Here are 7 simple tips on how to cut plywood using a circular saw and making it look great. Following each one of them will lead to a smooth finish, a safe environment, and a happy customer.
How to Cut Plywood With a Circular Saw
Getting the Right Blade
When buying a circular saw, also account for new blades. Although you may find some use for the blades that saws are sold with, they are generally low quality and need replacing for professional-level work. Finding the right blade for the job will make your job easier and your work cleaner. But, what is the best circular saw blade to cut plywood?
When cutting plywood sheets, you want to be using blades with plenty of teeth. More blades mean a cleaner cut, especially for rip cuts (cuts along the grain of the wood). You will also want blades that are designed for cutting laminate.
The secret to a cleaner cut is the tooth count. You don’t need to buy a blade with more than 100 teeth in order to get a clean cut – carbide blades with at least 40 teeth make for excellent blades for very fine cuts. Remember, though, that a blade with more teeth is more likely to grow dull in parts. Pay attention to how sharp the teeth are after use to maintain high-quality work.
Finding a blade that is specifically designed for dealing with laminated wood or finished cuts will improve the quality of your cut as well. The plywood blade generally has a higher number of teeth, but check before buying.
If you choose to use the blade that came with your circular saw, it is likely that your work will suffer. Researching and buying a number of specialized blades for different woods will help you finish your jobs cleaner and with greater accuracy and also helps you complete the task faster when cutting 4×8 plywood with a circular saw.
Setting the Blade Correctly
Before making any cuts, take the time to set your blade correctly. It doesn’t matter how brilliant your equipment is, if you are too shallow or too deep with the blade it will not give you the professional finish that you and your customers want.
The blade should go through the wood by no more than half a carbide in length. Setting the blade to go through at half its length means that it will not “chop” into the wood in front of and behind the point of contact.
You can run it deeper than this, but having a very deep cut can leave your plywood with obvious tooth marks from extra teeth dragging against the wood. This increases the chances of chipping and splintering as well, so it’s best to avoid plunging the entire blade through the plywood.
When you have a blade sticking out too far through the wood, you will have three problems:
- The blade will dull faster,
- The extra teeth will leave saw tooth marks as they are “chopping” the wood instead of cutting through
- A deep cut level can level your blade unstable and can lead to poor finishes.
Having too shallow a cut will leave you with an even worse finish. A shallow cut will lead to the blade not going through the board fully and the entire job will need to be repeated. This increases the chances of causing tooth marks, additional cut lines, and splintering.
Cut Your Plywood Best Side Down
When you cut through wood, the teeth are the main cause of splintering. To cut down on splintering being visible on your finished product, cut through the ply with the best side facing down.
Secure the plywood sheet with clamps with the side you want to show facing down – this hides the cut marks. You can secure it on top of a sawhorse or on the floor. You just need somewhere that won’t move as you cut, so the floor may be best for very important jobs that need strong support.
Clamps should fully secure the wood down and be weighted. You can weigh the plywood sheet down with a couple of 2 x 4 planks covering a sawhorse or by using any other material that will hold it in place, such as a foam sheet that grips the wood.
When cutting, you can also use your body weight to hold the ply in place if possible. This should only be done when on top of an extremely secure surface (most likely the floor!) so that you do not cause the wood to break under your body weight and risk serious injury.
Mark the Line
Taking a pencil to the underside of the wood will give you a steady line to follow when you are cutting. Although some people may want to rely on their guide block, having the straight line lets you check as you cut.
Obviously, the guideline should be straight and drawn on with a ruler. If you know that you will not be showing the side that you are drawing on, you may want to go over the line in a marker pen for better visibility when cutting.
A pro tip for using a guideline – score along the line with a penknife. This will give your circular saw a small divot to follow. This can take a few repeats with the penknife to make a deep enough line, but it will improve how clean your cut is.
Use a Guide (and Double-check It!)
Getting guide wood is simple from any hardware shop or you can make it yourself using offcuts and a decent ruler. If you are using offcuts, make sure that you have a finished side of the wood against your saw – you don’t want any unexpected bumps when cutting!
To stop your guide from moving, you should clamp it to the wood. Getting a strong and reliable clamp can save you a lot of money down the line. It will help your guides stay square to the wood and improve the quality of your cutting.
Attaching a guide to the wood gives you a hard boundary to follow with your circular saw. As you follow the line, the guide will help you keep your cutting consistent and on course.
Measure the shoe of your circular saw so it sits comfortably against the guides. Check both these measurements with a ruler at various distances, not just at the bottom – you don’t want to find out halfway through a job that your guide has taken your saw off the mark!
Tape Your Plywood for Crosscuts
When cutting across the grain of the wood, you’re more likely to get splintering or chipping. As the saw moves through the wood, it doesn’t have a clean line to follow like when rip cutting. The tape can be a lifesaver if you don’t have a specialized blade for this kind of job.
Both for the sake of keeping your workspace tidy and getting a clean-cut, you can tape along the top side of your wood to reduce splintering and chipping. Ideally, you want to get a blade specifically for cutting laminate. If that is not possible, taping is the next best option.
The tape will hold everything in place and ensure that there are no chips or splinters on the best side of your wood. When removing the tape, peel it off at a 90° angle to prevent it from damaging the topside. Tearing it off straight can take the veneer with it.
Slow and Steady Cutting
Make sure that you have as few cuts as possible (ideally only one) and that cut is slow and steady. Stopping will leave tooth marks in the wood and cause an uneven finish, potentially ruining the job.
Good space management is key to this. Know where the cable for your circular saw is – accidentally pulling on the lead can cause the saw to pull off course during the cut. This could lead to either a cut that runs away from your guideline, ruining the piece of wood, or potentially even cause serious injury.
Be conscious of where your blade (and everything attached to it) is!
Following these steps will help you get clean cuts every time. Taking the time to properly prepare and readying the plywood sheets to be worked on will improve your work tenfold. A steady, consistent approach to cutting will give you the cleanest finishes and the happiest customers.
Remember to look at your blades for dullness and the number of teeth – knowing how to use different but similar blades for various tasks can take you from being a woodworker to knowing how to treat and deal with plywood as an expert.
Let us know in the comments down below if you have any question about ripping plywood with a circular saw.