How to Cut a Straight Line with a Circular Saw

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Cut a straight line with a circular saw looks easy enough. However, even a skilled carpenter cannot boast of making a perfectly straight cut without using a guide. No one can freehand a cut without drawing a line to follow either. It takes a lot of practice to become confident with your circular saw, but the right tips make a world of difference.

 

In this article, we will go over how to make a circular saw guide to cut a straight line with a circular saw and how to use a straight metal edge instead. We’ll also discuss which method is the best for different cases.

 

Before you start, please be advised that circular saws are dangerous. Please follow the manufacturer’s instructions and ensure you are not using it unsupervised if you are a beginner. If you are a beginner, learn to take care of your tools here.

 

Using a straight metal edge as a guide is an excellent way to cut a straight line with a circular saw if you haven’t made a proper guide or left yours at home. It follows the same principle as a prepared guide, except you have to consider the distance between your blade and the base every time you cut.

 

What You Need

Before starting your project, here’s what you’ll need:

  1. A Metal straight edge, either four feet or eight feet depending on the width of the board you are cutting.
  2. A metal ruler or measuring tape
  3. a sharp lead pencil
  4. two clamps
  5. Foam insulation board or four three-foot ribbed down 2”x4” wooden planks

 

Step One: Secure your Board

First things first, we have to secure the board you want to cut so that it doesn’t move while it’s being cut. We also want to place it so that we don’t cut anything underneath it, like your work table. You can put it over a waste sheet of insulation foam or place ribbed down 2”x4” wooden sheets.

 

Step Two: Mark and Measure

You need to measure the distance between the blade from the base on either side of your circular saw. Once you choose which side will face the cut, write down the distance between the blade and the base on the opposite side, facing away from the cut. Add that number to the width you wish to cut and mark that with a pencil at the top and bottom edge of the wooden sheet you are cutting.

 

Step Three: Clamp the Straight Edge

Place the straight edge flat side down on your wooden sheet. Align the straight edge with the top and bottom marks you made and secure clamps on either side to ensure it does not move. If the straight edge has a thicker side, make sure it’s facing the cut so that your saw has more leverage.

 

Step Four: Start Cutting

Place your saw with the shoe pressed against the clamped down straight edge. Align it for the cut and turn the blade on while keeping it a few millimeters away from the start point.

 

Once the blade runs at top speed, slowly start pushing it forward using both hands to keep it steady. It is hard to keep it straight initially, but once you’re a few inches into the cut, the saw prefers to stay moving along a straight path.

 

Step Five: Finish Cutting

Push your blade on a little further than where the board ends before pulling it away and turning it off. This makes sure that the end doesn’t curve to one side. Step back and admire the straight edge you just cut.

 

The best method for beginners when using a circular saw is to rely on a guide. Even professionals rely on a guide for projects in which the edge line is essential, like cabinetry or flooring.

 

What You Need

  • Half inch-thick sheet of plywood
  • a measuring tape
  • A straight fence post
  • Wood glue
  • hammer and nails
  • pencil
  • Insulation foam or 2”x4” wooden planks
  • two clamps

 

Step One: Glue and Nail Your Fence

Glue your fence onto the sheet of plywood. While attaching your fence post, make sure that each side of the fence is wider than the base of your saw. Wait for the glue to dry, and then nail it down onto the plywood with a hammer to make it extra secure.

 

Step Two: Cut the Guide

Place the saw on one side of the fence and push it along while pressing against it to keep it straight. It will cut off all the access wood. Repeat the process on the other side of the fence to accommodate the other side of the base.

 

Step Three: Prepare Your Board for Cutting

Now your guide is complete. You can follow the same steps as when using the straight edge to ensure that your board is stable enough for cutting. Since things moving unexpectedly cause the most accidents.

 

Step Four: Mark Your Measurements and Start Cutting

Measure how much to wish to cut and mark the top and bottom of the sheet of wood. Notice how we did not have to accommodate the circular saw base. This saved us time and left us with less margin for error.

 

Step Five: Clamp Your Guide

Now decide which side of the blade will face the cut and place the guide onto the plywood with the matching side facing the cut. Align the guide using the marks at the top and bottom of the sheet and clamp it down at both ends.

 

Step Six: Start Cutting

Start and finish cutting the same way you would while using a straight edge as a guide. Step back and admire your work.

 

Our Final Thoughts

Using a guide to help you cut a straight line with a circular saw makes it easy for beginners to get professional-level cuts. You can save time in the long run by preparing a guide for your saw. If you don’t have time to make a guide or forgot your guide at home, you can also use a straight edge but have to accommodate another measurement while cutting.

 

Always be safe while using a circular saw since it’s the most dangerous and the most helpful tool in carpentry.