A speed square is an indispensable tool for carpenters, DIY enthusiasts, and homeowners alike. Whether you’re a seasoned professional or a beginner, understanding how to use a speed square effectively can significantly improve the quality and efficiency of your work. In this guide, we’ll explore the many uses of a speed square, including making accurate cuts, checking angles, and more.
What Is a Speed Square?
A speed square, also known as a rafter square or triangle square, is a triangular-shaped measuring tool primarily used in carpentry and construction. The speed square’s name comes from its ability to perform multiple functions quickly. Its compact size and durability make it a popular choice for both professionals and DIY enthusiasts.
Typically made of metal or high-impact plastic, this multi-functional tool combines the features of a try square, miter square, and protractor. This allows for quick and accurate measurements, marking, and guiding cuts on various materials, particularly lumber.
Types of Speed Squares
Speed squares come in various types, each designed to cater to different needs and preferences. These are the three most common types:
Standard Speed Square
The most common, the standard speed square is typically made of aluminum or high-impact plastic and measures 7 or 12 inches along the right-angle side. Suitable for most carpentry and DIY projects in the United States, they feature imperial measurements (inches) and are marked with common rafter angles.
Metric Speed Square
Metric speed squares are similar in design to standard squares but use the metric system for measurements. These are more common in countries that primarily use metric units.
Digital Speed Square
Digital speed squares are a modern twist on the classic tool. They incorporate electronic components to provide precise digital readouts of angles and measurements. While more expensive than traditional speed squares, digital versions offer enhanced accuracy and can be particularly useful for complex projects or when working with unusual angles.
Choosing the Right Speed Square for Your Project
Selecting the appropriate speed square depends on several factors, including the nature of your project, your preferred measurement system, and your budget. Consider these points when making your choice:
- Additional features: Some squares include extra markings for common angles or built-in level vials
- Budget: Standard squares are affordable, while digital versions offer advanced features at a higher price point
- Material: Aluminum squares are lightweight and durable, while plastic ones are less expensive and won’t scratch delicate surfaces
- Measurement system: Choose between imperial and metric based on your location and project requirements
- Size: Smaller 7-inch squares are more portable and suitable for quick measurements, while larger 12-inch squares offer extended reach for wider boards
Using a Speed Square
A speed square is a jack-of-all-trades in the world of carpentry tools. It has three primary functions, including making straight crosscuts, marking ripping cuts, and checking for square ends, as well as two advanced uses—marking angles and checking blade alignment. Here’s a look at how you can use a speed square:
Make Straight Crosscuts
One of the most common uses of a speed square is as a guide for making straight crosscuts with a circular saw. The speed square’s sturdy construction and right-angled edge provide a reliable guide for your saw, reducing the likelihood of crooked or inaccurate cuts.
You can hook the square’s lip on the edge of the lumber nearest to you and run the saw’s shoe along the square’s edge as you make the cut. This also works on boards that are wider than the square, provided that the saw’s shoe remains in contact with the square’s edge through the entire cut.
Mark Ripping Cuts
When you need to reduce the width of a board, a speed square can help you mark straight lines parallel to the board’s edge, providing accurate and consistent ripping cuts.
For example, if you want to take 2 inches off the width of a board you would hook the square’s lip over the edge of the board and place your pencil on the square’s 2-inch mark. Then, just slide the square down the board’s length, holding your pencil steady and keeping the lip of the square flush against the edge as you go.
Check for Square Ends
A speed square is ideal for checking for square ends—it only takes about two seconds.
To check for square ends, place the square’s lip against one edge of the board and align its 90-degree corner with the corner of the board. If the square’s edge isn’t flush with the board’s end, you’ll need to trim it before cutting to length.
Mark Angles
A speed square doubles as a protractor, so you can mark angles from 0 to 90 degrees.
For example, if you want to mark a 30-degree line, you would begin by pushing the square’s lip against the edge of the workpiece, then pivot the tool on its 90-degree corner until the 30-degree mark on its hypotenuse aligns with that same workpiece edge. Make your mark along the pivot side of the square.
Keep in mind that the square’s degree markings are relative to a line perpendicular to the workpiece’s edge. The complementary angle (60 degrees in the example above) is relative to the edge of the workpiece.
To keep the square steady while marking, place your thumb against the pivot point, with your first two fingers on the square and your third and fourth fingers on the workpiece.
Check Blade Alignment
A speed square can help you check and adjust your circular saw blade’s alignment to the shoe to improve the accuracy of your cuts. To do this, set the blade for a full-depth cut at 0 degrees and flip the unplugged saw upside down. Pull back the blade guard and position the speed square with one side against the saw’s shoe and the other against its blade. Make sure the square is not touching any of the blade’s carbide teeth.
If you notice a gap between the blade and the square, adjust the saw’s shoe until the square sits flush against both.
Maintaining and Caring for Your Speed Square
Properly maintaining your speed square can help it last longer while providing more accurate cuts. Follow these tips to keep your tool in top condition:
- Clean regularly: Wipe down your square after each use to remove dust and debris
- Store properly: Keep your square in a dry place to prevent rust (for metal squares) or warping (for plastic ones)
- Check for damage: Regularly inspect your square for signs of wear or damage that could affect its accuracy
- Avoid dropping: While speed squares are durable, repeated drops can affect their accuracy over time
- Calibrate digital squares: If you have a digital speed square, follow the manufacturer’s instructions for calibration to maintain accuracy
Common Mistakes To Avoid When Using a Speed Square
Even experienced users can make mistakes with a speed square. Here are some common errors to watch out for:
- Misreading measurements: Double-check your readings, especially when switching between different sides of the square
- Neglecting to secure the square: The square needs to be firmly held in place to prevent slipping during marking or cutting
- Using a damaged square: A bent or chipped square can lead to inaccurate measurements and cuts
- Ignoring complementary angles: Remember that the degree markings on the hypotenuse are relative to a perpendicular line, not the edge of your workpiece
- Overlooking the square’s limitations: While versatile, a speed square isn’t suitable for every measurement task. Know when to use other tools
Speed Square vs. Other Carpentry Tools
While a speed square is incredibly versatile, it can’t always be used in place of other common carpentry tools. See how the speed square compares to the framing square and the combination square:
Speed Square vs. Framing Square
A framing square, also known as a carpenter’s square, is larger than a speed square and typically L-shaped. While both can be used for marking right angles, a framing square is better suited for larger projects and laying out stairs or rafters. A speed square, being more compact, is ideal for quick measurements and as a saw guide.
Speed Square vs. Combination Square
A combination square consists of a ruler and a removable head, offering more versatility in some aspects. It’s excellent for measuring depths and checking the flatness of surfaces. However, a speed square is often quicker to use for marking angles and guiding saw cuts.
Our Conclusion
The speed square can significantly enhance your woodworking and carpentry projects. From helping you make accurate cuts to checking angles, this simple yet ingenious device offers a wide range of applications for both professionals and DIY enthusiasts. Remember to choose the right type for your needs, maintain it properly, and avoid common mistakes to get the most out of your speed square.