Last Updated on 5 months by James D. Miller
In carpentry projects, a craftsman often needs to make perfectly square cuts on a piece of timber which is quite difficult to accomplish using just a hand-saw. To be able to make intricate cuts and wedges in wood, carpenters need specialized tools, and circular saws are one of them.
Circular saws are designed to perform a straight and a flawless cut in wood. They are perfect for cutting four-sided holes on timber. This article will give you an elaborate view on how to cut a square hole in wood with circular saw.
There is a large number of tools available that can make the cut of your desire, but they are not within reach of DIY project-makers or homeowners. Expert craftsmen, carpenters and factory workers have expert knowledge in using these tools and can gain easy access to them, but you may not have that access.
It is not the case with circular saws though. Circular saws are readily available at any tool shop and can be used to make square holes in wood easily. Anyone with minimal wood-working experience would be able to cut their desired four-sided dimensions on wooden blocks. Let’s read to find out.
Parts Of The Circular Saw
Table Of Contents
Before you start your wood-working project, make sure all the segments of your circular saw are up-and-running. Let’s take a quick look at the different parts of a regular circular saw:
- a) Blade Guard: It prevents the blades from binding against obstacles, and also safeguards you from the sharp teeth of the tool. Make sure that it retracts and releases easily back and forth before the plunge cut.
- b) Blades: If the blades have gone rusty, the first thing to do would be to change it. Never ever settle for damaged or rusty blades. Carbide-finished combination blades would be best to cut through the plywood and solid wood.
- c) Shoe or base-plate: This part extends below the machine, and helps the user to make straight cuts and safeguards him from kick-backs. Make sure the lever and the shoe work perfectly before using the saw.
How To Cut A Square Hole In Wood With Circular Saw
Plunge Cut Technique
- a) Mark the cutting area: At first, mark the area that you want to cut on the wooden panel or block. After that, make sure that your wooden lay-out is clamped tightly so that there is no movement once the cutting begins.
- b) Fix the cutting angle: Setting the angle of cut would be the next thing to consider. To set the angle of the shoe or the baseplate, simply loosen the lever that is fitted to an angle-measuring gauge just above the shoe. There are numbered indicators on the gauge that would help you to tilt the base-plate to your desired angle. After the angle has been chosen and the baseplate tilted, just lock the lever in position and you are good to go.
- c) Set the blade depth: The blade of the circular saw is usually set at the minimal depth by default so as to prevent a big circumference of the blade from protruding at the bottom which might prove to be dangerous if ever you get distracted.
Hold the shoe or the baseplate, against the “reference line”—reference line being the first mark of the square that you have drawn on your project. As soon as you have aligned the marking with the shoe, then tilt the circular saw up. Position yourself on the side of the circular saw, and hold it against the reference line, tilted upward with one of your hands.
While you do this, ensure that you are standing as far from the tool as possible, and also remove any clothing material that is long and flowy, like a scarf, or a shirt with long sleeves, a dress with frills, or any such flimsy wearable items. In other words, wear something tight-fitting.
Also wear safety goggles and face-masks to protect your eyes and face from wood chips splintering. Wearing ear-covers will also be useful since certain saws make a dreadful noise while cutting through the timber.
- d) Start cutting: Once you are ready, switch on the power machine. As the blade starts rotating, slowly lower the saw from its tilted position toward the wooden project until the blade touches the wood and starts grinding it away.
After you have set this motion, gently slide the circular saw blade forward or backward, depending on the dimensions marked on the wooden piece.
It is not necessary that your circular saw blades will be able to cut all the way to the ending centimeters of the reference line—and that is where the hand saw jumps in. Cut all the dimensions up to as far as the circular saw can reach—the last few centimeters or inches could be trimmed out with a hand-saw.
This is how a plunge-cut technique could be used to cut a square-shaped hole on a wooden panel using a circular saw. This technique becomes particularly useful when you need to cut out square or 4-sided wedges to make the entry-way to a dog’s kennel or a cat’s litter box.
Speed or Rafter Square Technique
Speed squares have raised wedges that fit perfectly onto the edges of a timber piece where you need to cut a perfect square in.
Place the rafter, then with the help of the numbers marked on the rafter, take your desired measurement.
You can easily cut 45 degrees and 90 degrees with the help of a speed square—any other angular cuts are also possible.
As the rafter slides along the edges of your timber, you can slide it up and down, and when you are happy with the measurements, simply take your circular saw and cut along the straight edge of your speed square.
Safety Tips While Using A Circular Saw
A circular saw is one of the most useful gadgets out there—yet the most dangerous! Therefore, keeping some safety tips within knowledge would prove to be handy around the house or workshop premises.
Circular saws are powerful gadgets—running at 13-15 amp motors, with the 7-1/4” blades rotating at a speed of 5000 RPM. You could use a hand-held miter circular saw, instead of the bench-positioned circular saw, whichever is more suitable for your woodworking projects.
- a) Keep things away from the blade track: Just remember, that a circular saw does not move in a fixed path, therefore, the only thing that is responsible in maneuvering it along a fixed path is your hands. The first thing is to therefore ensure that your body and your clothing items are as far away as possible from the cutting path of the power-machine.
While working with the circular saw, at all cost. refrain from placing your free hand at the front or behind the saw. Similarly, do not rest your foot anywhere near the saw, or rest your free hand on the side or underneath the wooden panel lest the cutting blades come too near.
- b) Run the machine up the kerf: The second thing to remember would be to drive the circular saw up the kerf—the kerf being the path-way which the saw has already cut in the wooden panel. The saw blades face a minimum obstacle when it is riding on the kerf.
If it runs on a new pathway, it might retaliate, jump or twist back on you, unable to overcome the pressure or resistance. To save yourself from any such thing happening, simply drive the saw along in a straight path, along the kerf if possible.
Another useful way to prevent accidents from kick-backs is to simply place supporting wood pieces or scrap blocks close together underneath the wood-panel you want to cut.
- c) Ensure the blades do not protrude too deep: Thirdly, ensure that the blades of the saw underneath the wood-panel are not extending too deep— protrusion between 1/8” and ¼” would be the safest bet. If the extension of the blade below the panel is deeper, the panel and saw both would be quite unstable leading to recoiling or kick-backs.
To adjust the depth of the blades, at the first stop the cutting machine, loosen the depth-controlling lever, then swivel the baseplate up or down—never ever adjust the plate while the saw is in motion. After the depth has been adjusted, just tighten back the lever.
- d) Do not yank off the saw when it is on: Home-users and DIY project makers must maintain precautions more sincerely than expert factory-level woodworkers. Carpenters possessing the highest level of cutting skills are often seen to be yanking off the miter while the blades are rotating—this is done to minimize time-consumption, and workers at that level of expertise can guarantee safety under the most adverse of conditions.
However, DIY project people do not need to play around with the mighty saw and bring unnecessary life risks to themselves. In the simplest terms, do not remove the machine from the kerf while the blades are in motion—wait for the blades to stop rotating and then retract it.
- e) Do not remove the blade guard: Blade guards should always be on—it should never be removed or blocked in any way. The blade guard is designed in such a way, that as soon as cutting is complete, it springs back to its original position, preventing the spinning blades from contacting anything on its way further protecting the machine and the handler from accidents caused by recoil.
- f) Store it in a flip-back position: After you are done with using the machine, turn it off and then flip it in an upside-down position—just like the way a turtle looks when it flips shell-down and legs-up.
Also, after usage, store the machine inside open-wedged carry-cases that are also made up of a steel-friendly material that prevents the blades from getting scuffed. Having said that, never place the saw on concrete since it might damage the blades.
Q.1) How will I change the saw blades?
Ans: Remove the locking nut at the center of the blade with a spanner tool. Certain brands of circular saws come with L-shaped devices that also help.
After this, you would need to lock the blade lever so that the blade does not move. Next, twist the L-shaped device anti-clockwise which will loosen the nut bolt, allowing you to dislodge the blade.
Q.2) How can I cut squares with beautifully straight edges?
Ans: You can use speed square tools the usage of which has already been mentioned in this article. You may also get yourself a long piece of a wooden block with a smooth edge (10-12 inches wide birch plywood works wonders), and then clamp it down on either end of the lumbar.
After that, simply align the saw-base or shoe along the straight edge of the wooden block, and start cutting.
Q.3) How can I make an angular cut without chances of kick-backs?
Ans: While trying to make angular cuts, the saw guard loses control and makes the machine wander, bind or kick-back. To prevent this from happening, prior to the cut, retract the blade guard, start the motor and start cutting gently into the lumbar. Once you are deep into the cut, release the blade guard, and continue cutting.
Q.4) What kind of blade should I opt for in order to complete home-scale carpentry projects?
Ans: For construction and landscaping work, go for the 24T blades. For finer wood-working projects, like carpentry, go for 40-60T blades.
Circular saws are easy to use and are readily available at any tool-shop around the corner. But since they are powerful gadgets with sharp blades, maintaining safety precautions is a must. Wood-workers often want to cut quadrilateral-shaped holes on wood using circular saws and look for useful tips.
This article has shared some useful tips on how to cut a square hole in wood with circular saw. The plunge cut technique is quite popular, and not to mention the blessings of the rafter square that helps create those perfectly straight edges on timber.
Circular saws are some great tools to make amazing carpentry projects at home and at the factory. If you have any more queries regarding this amazing machine, feel free to reach out to us.