Last Updated On March 18, 2023
Did you know that the hardest job is to cut straight with a circular saw? The thing about power tools is they have a motor inside that is powerful for obvious reasons. Controlling them for straight cuts pinpointing a specific location or going on a straight line for a rip cut is a tough job.
In the case of making use of a circular saw, maintaining a cut line for cutting straight is impossible with a cutting guide. Even if you want to cut plywood, the vibration from the circular saw is enough to deviate you from going on straight lines and getting fine rip cuts with a circular saw blade.
So, the question emerges, how to cut a straight edge with a circular saw? The answer is, to use a straight edge. To cut straight lines with a circular saw blade, even if it’s a table saw, you need a cutting guide or else known as a straight edge guide for circular saws to achieve an accurate cut.
In this article, we will give you tooltips on how you can rip-cut a narrow piece going on straight lines to get a straight edge on every rip-cut you make with a circular saw.
What is a Straight Edge guide?

Before jumping into the how-to part, it’s important for you to know the tool you are about to use. So, here’s a little introduction to a straight-edge guide.
For a standard, we would choose the Kreg straight-edge guide which is the most-used straight-edge guide. Most people would pick kreg accu cut, but it is for track saws that have rails. The kreg accu cut is so vastly used that rip cuts made using kreg accu cut are actually called kreg rip cut.
A straight edge is basically a cutting guide tool for achieving a straight cut on wood or other materials like metal. It is actually used for two purposes. You can also check the straightness of a rip-cut line that you have drawn using a straight-edge guide.
The emergence of a straight edge came into presence because no matter the straight cut you claim to make in your DIY projects, without a straight edge guide making straight cuts with a circular saw is not possible. They either have to have a great perception of how to measure a straight line on wood while you make straight cuts, or they have godly accuracy.
But for people like us, we need guides to keep the blade straight even working on a plywood base while going for longer cuts.
How Can I Cut Straight Lines with a Circular Saw?
It’s a step-by-step process. To make straight cuts with a circular saw, you need to learn how to use a straight edge to mark a straight line. After that, you can go on the straight line without making a Kreg rip cut with your regular circular saw if you know what I mean.
Using a Straight Edge to mark a Straight Line for a Straight Cut

Step 1

First, you need to fix the platform and fix the cutting material on the platform. The platform needs to have a height good enough for you to work on it.
Step 2

Now you have to determine exactly where you need to make the rip cut and how far apart each cut would be. The distance between each cut is the width of the planks that you will have after you have used your circular saw.
Step 3

It’s time to mark the material board exactly at the length you determined. You have to mark on both ends of the board the plank size you determined. one on the top edge, the other on the back edge.
Step 4

After marking, use a deep pencil to draw straight lines on the board. Remember, drawing the lines straight will ensure that the cuts you make will be straight cuts. To make straight cuts with a circular saw perfectly, make the line as visible as you can by running the pencil several times.
Step 5

Keep drawing lines on the board using the pencil with the help of the tool. The beauty of your DIY project will depend on how well you have measured and marked the line with a pencil for a straight cut with your circular saw.
For Table Saw
For using the straight-edge guide for your table saw, you have to use a clamp to attach the guide to the board just like the table saw is attached to keep making straight cuts.
Using Straight Edge to Go Straight with Circular Saws
It’s time for you to make straight cuts with your circular saw. To do that prepare the saw by attaching the saw blade and plugging it in or attaching the battery.
Also, don’t forget to measure and select the correct blade size according to the depth of the material board. Let’s begin the process.
Step 1

Line up the blade of the circular saw along the first line that you have drawn using a pencil. How well you align the blade of the circular saw will determine how straight you go through the marked line.
Step 2

Mark the end of the circular saw base plate on the wood by the side of the edge and measure the distance between the line of cut and the end of the base plate of the circular saw.
Step 3

Go to the other side of the material board and mark the board using the distance you measured. Using the straight edge guide, see if the marking is straight or not. You can use a combination square or a speed square to do the job.
Step 4

Line up the straight edge guide along the marking of the base plate and clamp it on the board according to the markings you made.
Step 5

Place the circular saw, and align the blade of the circular saw with the cutting line to see if the alignment of the edge guide is perfect or not. If it’s not, the cut will not be straight. If the alignment is not the same, follow the process again and mark more carefully using the speed square.
Step 6

See if the alignment is perfect on not. If it is, Press the trigger, wait for the blade to reach its full speed, and make the cut with the circular saw.
Step 7
For every plank to have the same straight cut, follow the procedure of aligning the edge guide every time on the cutting board. That way, with every rip cut you make, you will get an equal-sized plank.
Now, the most important part of using a circular saw like a 4 1/2 circular saw, 7 1/4 circular saw, or whatever it is, maintaining the safety precautions. I know you want to make straight cuts with a circular saw but without maintaining these safety measures, the circular saw you are using, will be the cause of you getting hurt.
Safety Measures
Taking safety precautions is very important because without them you can cause serious harm to yourself. You won’t be able to make long cuts with a circular saw. Instead, you will end up injuring yourself and others.
Wearing Safety Goggles

Wearing safety goggles at all times while using circular saws or any power tool is mandatory. Power tools are used on different surfaces either to cut them or to attach them. This activity can shoot particles from the materials of the surfaces upwards and they can hit us in our eyes.
This incident can go as far as causing permanent blindness. So, be very careful and wear safety goggles.
Using Ear Protectors

The thing that can happen to our eyes, can happen to our ears as well. So, we have to protect our ears from debris entering. That’s why we need ear protectors.
Working Gloves

Losing a finger while working with a circular saw is the most common accident that can happen. The only way to prevent something like this from happening is to use heavy working gloves.
In event of a sudden blade opening or the blade getting detached from the circular saw, work gloves will protect your hands from getting cut.
Wearing Dust Mask

These procedures of cutting with the blade generate small residue that cannot be seen by the naked eye but travel in the air. These residues can get inhaled through our nose and mouth and travel to our lungs.
That cannot be good for anyone, can it? The best thing that you can do to prevent it from happening is to wear a dust mask. It will stop all the residue from entering your lungs.
Keeping Everyone Away

Keeping everyone away from the place of your work is more than necessary. The safety measures that I have mentioned, are obvious for you to take.
But when you are working at home, you can’t expect everyone to maintain them. Everyone will be minding their own business, doing what they do.
If you have a workstation, it’s fine for you to work there. No one will enter.
But if you are working inside your home in a room that is not your workstation, and you’ve just turned into a temporary place for doing woodwork, make sure everyone is away.
If someone suddenly enters and something happens, it will be fatal. And you are working with blades. Any accident will take a huge toll.
And if you have kids at home, you are in the biggest danger. make sure the kids are far away.
FAQ’s
How do you make a straight edge with a circular saw?
Attach a straight edge guide to the board, clamp it down securely, and make the cut with the circular saw blade flush against the guide. Repeat as needed.
How do you cut a 2×4 straight with a circular saw?
Mark the cut line, attach a straight edge guide to the 2×4, clamp it down, and cut with the circular saw blade flush against the guide. Use protective gear and caution.
Final Verdict
This is how you perform straight cuts with a circular saw. You would have to follow each and every step that I have shown above.
Some people might say that you can see through a sheet of plywood to perform a rip cut with a line drawn using a normal ruler with the blade at full speed without using any long edge guide.
This statement is not correct. The power of the circular saw with push you off the line if you’re going for quite some length. The easy way to cut straight is using a guide.
And remember to maintain all the safety measures. Without them, anything can happen.

This is Ahmed Shuvo, an enthusiastic tool enthusiast with a passion for saws, especially circular saws and miter saws. I have written blog posts and conducted research on the proper use and maintenance of these tools. I am also a DIYer who enjoys making wooden projects and always striving to improve my skills. I am confident in my expertise and eager to contribute to the growth of this industry through my writing.