A circular saw is the best tool to cut down a large plywood sheet.
With a few accessories, it's possible to cut a plywood sheet accurately into the sizes you need.
Things You'll Need
- Circular Saw
- Sheet of Plywood (preferred dimensions)
- Quick Grip Clamps
- Masking Tape
- Sacrificial Sheet (Insulation sheet, another plywood sheet or MDF sheet works)
- Straight Edge (a plank with perpendicular edges or a level will do fine)
- Speed Square
- Measuring Tape.
There are two ways to cut a plywood sheet with a circular saw without splintering.
- Using a straight edge to maintain a straight line
- Using a circular saw track/guide (Kreg Accu-cut or Kreg rip-cut)
In the first method, you need to make a straight edge first and then move on to the cutting.
In the second method, you need to have a Kreg accu-cut or rip-cut jig. If you use your circular saw a lot, then it's an amazingly handy jig to have in your shop.
In both methods, you need a flat surface on which you can do the cutting.
You can't use your table as the saw blade will make marks on it.
The solution is to use a cheap, flat material that's large enough to place your plywood sheet on it.
You also need to make sure that the material is soft so that it doesn't dull your circular saw blade.
The best material for this purpose is a rigid foam insulation board.
Now, it can come in different colors depending on the brand, so don't let that confuse you.
We'll be using a rigid foam insulation sheet (white color) in both our methods as the base for placing the 3/4" thick plywood.
Method 1: Using a straight Edge to cut plywood
In this method, a straight edge is used to guide the circular saw during the cut.
You can make a straight edge using scrap wood.
First, place the rigid foam insulation sheet on the work surface.
Next, place the plywood onto the sheet.
Fix some masking tape over the plywood, along the path you wish to draw the line of cutting.
The masking tape is for preventing splintering in the wood.
Use a speed square and a carpenter's pencil to draw the mark on top of the masking tape.
If the length is more than speed square, consider marking both ends with the speed square and joining those points with a straight edge or level.
To set the depth of the circular saw blade, keep the blade over the edge of the plywood.
Set the depth slightly lower than the total thickness of the plywood.
Measure the offset distance from the shoe of the saw to its saw blade using a measuring tape.
Transfer the offset distance to the cut line.
Take the straight edge and keep it aligned with the offset line.
Align the saw's blade with the cut line.
Make sure to place the blade on the scrap side of the line to get the exact dimension you need on the usable side of the sheet.
and begin cutting along the cut line using the straight edge/level as a guide.
Cut along the cut line until the plywood is split into two.
Remove the masking tape and check for splinters or cracks along the edge of the cut sheet.
With this step, you should now have the plywood piece you need.
Method 2: Using a Circular Saw Track/Guide
For this method, you will need to use a circular saw track like the Kreg Acc-cut or the Kreg Rip-cut.
I'll show you how to do both.
Using Kreg Accu-cut Tool
Begin by measuring and marking the line of cut along the length of the plywood.
For this, you can use the speed square or the track of the Accu-cut, along with a carpenter's pencil.
Attach the sled of the accu-cut onto the circular saw.
Align the track to the cut line.
There is no need to clamp the Accu-cut as it comes with anti-slip pads underneath the track.
Attach the sled onto the track of the Accu-cut and begin cutting along the line.
Cut until you go through the track fully and now you'll have an accurate piece of plywood that you wanted.
Using Kreg Rip-Cut Tool
Begin by attaching the sled with the circular saw to the track.
Using the edge of the plywood as a reference, press the rip guide flush against the factory edge of the plywood.
Mark the needed width and lock down the sled to the track.
Make sure the blade is just outside the line of cut with the blade on the waste side (the part you aren't using) of the line.
Begin cutting and move it all the way through the plywood.
You can keep your foot on the plywood if the cutting width falls towards the middle of the sheet.
That will keep the plywood more securely due to your weight.
Cuts of up to 24 inches wide can be made with the Rip-cut guide.
With that step, you'll have a plywood piece cut to the size you wanted.
Tips for safety and accuracy while cutting plywood with a circular saw
- Try to cut along the grain instead of across the grain to reduce blowout.
- Wear protective gloves while working with plywood to ensure safety from splinters and cuts.
- Make sure depth is set all the way down before you begin adjusting.
- Before making any adjustments, make sure the saw is unplugged.
- If the piece completely seperates from the wood, let it fall. Never try to catch it while holding a runnning saw in your hand.
- While marking, never mark just as a point. Instead, mark it as a 'tick' mark or a 'crow's foot' mark. Doing so helps in identifying the point to be cut easily.
- Kickback is extremely dangerous and must be prevented at all costs.
- Using masking tape before drawing the mark on it can help reduce burrs to lend a more pleasing finish.
- Make sure to cut outside of the line, so the wood piece that you intend to use has the correct dimensions.
- Use a rasp to clean and smoothen the cut after sawing. Alternatively, A hand sander or sanding paper can also get the job done.
- Once the saw is turned on, keep it steady but never try to force it back in case it veers off.
- Using excessive force will create pinch points in the wood leading to damage for both the user and the saw.
Frequently Asked Questions (FAQ)
Can you use a circular saw to cut plywood?
One of the best uses of the circular saw is to cut large sheets of plywood down to the required dimensions. Circular saws are particularly useful in making straight, miter, bevel, and other angle cuts.
A wide variety in the blades available has turned the circular saw into the ideal tool for cutting plywood and materials like wood and plastics, and even concrete.
How do you cut a plywood with a circular saw without splintering?
To cut the plywood without splintering, fix masking tape on the masking tape and use a blade with a high number of teeth. Make sure the good side of the plywood faces down while cutting.
This is because the blade of the circular saw spins in an anti-clockwise direction and will only leave splinters on the side from which the blade exits.
What is the best circular saw blade for cutting plywood?
6 1/2" - 60 Tooth - "Ultra Finish" is the best blade available in the market for cutting plywood. When selecting a blade to cut plywood, select the blade with the most number of teeth, so the splinter or blow-out amount is reduced greatly.
Do you cut plywood good side up or down?
When cutting plywood with a circular saw, it's best to keep the good side down. For cutting with a table saw keep the good side up.
This because the circular saw blade spins in the anti-clockwise direction while the blade of the table saw spins in the clockwise direction. As a result, splinters will form on the side from which the blade of the saw exits.
What is kerf loss on a circular saw blade?
Kerf loss in a saw blade refers to the loss in the dimension of wood due to the blade's thickness. A regular saw blade will have a 1/8th inch thickness, so an equal loss of 1/4th of an inch will occur on both sides of the marked line if cut along its middle. To prevent kerf loss, cut on one side of the line so the other side will lose no dimensions.
What can I use instead of a table saw to cut plywood?
A circular saw is an excellent tool to use for cutting plywood, instead of the table saw. The accuracy of the cut can be further increased if proper blades and guides are used.