Taking a heavy piece of equipment like a circular saw and planning to cut an exact straight line can be a bit daunting, especially for beginners. A lot of mistakes can happen, such as losing the line for your cut or the saw drifting away into the material that you need. But it’s not that difficult when you know how to create and set up a piece of equipment known as a guide bar.
A guide bar will make cutting with a circular saw in a straight line so much easier than trying to cut “freehand.” And best of all, you can make it with your circular saw. With 3 easy steps, we’ll show you how to make your guide bar and line it up with a board, ready to cut.
When you know all the necessary tips and tricks to craft your own guide bar, you won’t need to worry about cutting straight lines anymore. It’s as simple as applying your homemade guide bar and guiding your circular saw over the wood.
How To Cut Straight With A Circular Saw?
Gathering Your Equipment
Before starting any cut, you need to make sure you get all of the correct equipment ready. Being ready means that you have everything at hand whenever you need it.
This includes having your power tools ready to use, but not ready to start spinning before you need them to. Basic safety is extremely important with powerful equipment like curricular saws.
You will also have to make sure that you know how to use every piece of equipment used in the job. As the circular saw is a powerful piece of equipment, you need to pay it the due respect.
This includes knowing exactly how you handle it in all positions. If you find any technique in this tutorial that you are not sure about, try it out on a few pieces of scrap wood. The practice is the best way to improve.
You will need:
- Circular saw
- Sawhorse or workbench
- A scrap piece of thick board
- A thin piece of ply
- Screws that are shorter than your thick board and ply together
- A power drill
- Pen or pencil
- Clamps (at least 4)
- Safety equipment, including goggles and ear protectors
When you have all of your equipment, make sure that you do not have to lose cables lying underneath your workbench. As you will be moving while using the saw, you need to make sure there are no tripping hazards.
Protecting yourself when you are using power tools should always be your first concern. There will always be other pieces of wood; you can’t grow extra fingers. Taking time to safely set up, use, and put away your tools is the best way to ensure you have a long career as a woodworker or can simply enjoy your hobby for longer.
When you use a circular saw, the blade can spit out splinters, dust, and chippings, so you need to protect your body against anything that could fly towards you. Wearing proper protective equipment will stop avoidable injuries and prolong your career.
As sawdust will be flying towards you, goggles are necessary. You don’t want any pieces sticking in your eye as it can be uncomfortable at best and potentially serious at worst. A decent pair of goggles or protective glasses will be available for cheap at any good DIY or hardware shop.
Similarly, all saws can be very loud. You will need good ear protection to defend against the noise of the power tools. Most woodworkers today seem to be using a set of ear protecting earbuds, but traditional headphone style ear protectors do the exact same thing.
Although you don’t need to wear hand protection, you can if you want to. The most important thing about protecting your hands and forearms is not to wear baggy or loose clothing. Flapping material can get stuck in the mechanism and lead to serious injury. Remember, safety first!
Setting Up Your Workbench
Depending on whether you are using a sawhorse or a workbench, this process will be slightly different. You will need to make small changes appropriate to your setup.
Lay your board on your sawhorse or workbench. You will need to mark the line that you want to cut with a pen or a pencil. This helps with improving the accuracy of your cut as well as assisting in making your guide bar. When you have the line drawn on your board, you can remove it from the sawhorse.
Now you start making your guide bar.
Making Your Guide Bar
The guide bar is basically just two pieces of wood stuck together. It’s not a complex piece of equipment, but a guide bar will improve the quality of your cut significantly. It also saves on buying potentially expensive equipment that basically serves the same purpose.
Cut a section of the scrap board so that it is around 6 inches thick. This cut does not have to be straight as we will only use the factory-finished edge for our guide bar. All you have to do is make sure that the guide bar is long enough that you can rest it over the entire length of the board you want to cut.
Lay your ply on the sawhorse. This ply should now make the scrap board substantially thicker, which is exactly what we need. We want this guide bar to act as a support for our saw, so it needs to match up with the size and height of the saw’s shoe.
Place the board on top of the ply. Line up the “cut edge” with the outside of the ply; you will have the rough edge facing away from you and the factory finish side facing towards the middle of the ply.
Make sure that the scrap board is straight and screw the two pieces of material together. The board needs to be secure, so double screwing is a good idea. I’d avoid using glue as it is not as secure, but there is no reason you can’t use glue and screws together for an extremely immobile finish.
Now you can trim down the guide bar to the size of your circular saw.
Trimming the Guide Bar
You want the exposed ply (that is, ply not under the scrap board) to be the same width as the shoe of your circular saw. When we are making the cut, we need the scrap board to act as a guide that can keep the blade straight. If the exposed ply is larger than the shoe, the saw will not be secured against anything.
Take your circular saw and start the blade spinning. Match up the shoe so that it is tight to the scrap board section of the guide bar. Make the cut all along the ply. Your guide bar should now have a ply section that is equally as wide as your saw’s shoe.
Now you can set up your guide bar and begin to cut.
Setting Up Your Guide Bar
Before actually putting the guide bar onto the sawhorse, you must position the board you want to cut. Your pencil line should be clear and you need to clamp it down, preferably with at least two clamps.
Now rest your guide bar on top of the board, match the ply edge with the pencil line. You need this to be accurate as this is the line your circular saw’s shoe will follow.
When the guide bar is in place, clamp it down. You need this to be secure – unsecured guide bars will give you wobbly finishes and possibly even cause injury. Save yourself some money, some time, and a trip to the hospital by applying your clamps and checking them twice.
Making the Cut
Now your board and your guide bar are in place, get your circular saw back. This is actually the easiest part of the entire operation. You want the blade to line up with the ply and the shoe itself to match up with the scrap board. This will give you an extremely secure set-up for your saw, meaning you are less likely to make mistakes.
Match your shoe up with the guide bar so that your saw matches with both the guide bar’s ply edge and the pencil line. If these do not match up, you need to take apart your guide bar and figure out where you went wrong.
Start The Blade
Start the blade spinning before you reach the wood. A slow spinning blade can drag through the wood, meaning you actually damage it more than you need to. Slow blades lead to chipping, splintering, and wasted time cleaning up the finish later.
Now that your blade is spinning, you can begin to make the cut. Put slight pressure on the saw so that it sits tight with the guide bar. As you move through the wood, keep that pressure on so that your cut is straight.
Let the circular saw cut all the way through the board and allow the cut-off piece to drop to the floor. When you finish the cut, remember to lift the saw or you can fall forward, potentially leading to serious injury.
And there you have it – your straight cut with a circular saw.
Cutting a straight line with a circular saw is easy when you have the correct equipment. Making your own guide bar will save you plenty of time in the future, so you don’t need to worry about repeating most of this every single time you have to make this kind of cut.
The most important thing is taking the time to measure out the ply section and securing it tightly to the scrap board. The scrap board is only there to stop your saw from moving sideways – the ply actually secures the shoe and lines the blade with the wood.
Only a little bit of pressure is necessary to guide the saw through the wood, but it is still necessary to use clamps. A material that stops boards from moving too much won’t be suitable here – just make a decent guide bar!
FAQ About Making Straight Cuts with a Circular Saw
Can I Cut Straight With a Circular Saw?
Yes, especially if you are cutting a large piece of wood. All you need is a guide bar to stop your circular saw from moving and a few clamps. Then you can make the cut on any piece of material.
How Do You Make a Precise Cut With a Circular Saw?
Circular saws can be difficult to cut with precision if you don’t know how. The easiest way to improve precision is to make your own guide bar.
This is just a scrap piece of board screwed to a piece of ply. That ply should be the same width as the shoe on your saw. When these are put together and rested on top of a piece you want to cut, they give a strong basis for making any straight cut with a circular saw.
How Do You Cut a Piece of Wood in a Straight Line?
You can use a range of tools, but which one you choose depends on what kind of cut you want. For a consistent, clean-cut, use a circular saw with a guide bar.
Do I Need to Have a Specific Saw to Use a Guide Bar?
No, your guide bar is made by you, so you can adapt it to your needs. The ply section should match the width of the shoe and the scrap board needs to be tall enough that the shoe can rest against it. Aside from that, there are no other specifications that must be in place.
Do I Have to Make a Different Guide Bar for Each Job?
No – ideally, one guide bar will work with any material you want to cut. The only limiting factor is if the bar is long enough to be used.