Why do they call it a speed square?

Why Do They Call It A Speed Square?

The name “speed square” was coined by the inventor of the method, John C. Swannan.

He came up with the idea while trying to solve a problem he had encountered when using a compass to measure distance from one point to another. He found that the compass needle would not move at all when he tried to measure distance with it. After some experimentation, he realized that the reason behind this was because there were two different kinds of needles: a straight-edge needle and a curved-edge needle. When measuring with both types of needles, the straight edge would always stay parallel to the ground even if you moved your arm around very slightly. However, the curved-edge needle would move out of place if you moved your arm too much.

In order to overcome this problem, he invented a device which could measure distances between points without having to worry about the curved-edge needle moving out of place. He called it a speed square because it required him to turn a dial or slide a piece of paper across the table every time he wanted to make sure that the straight edge remained parallel to the ground.

However, the curved-edge needle would not move at all when measured with the straight edge. So, he decided to invent a device which could measure distances between points without having to worry about these problems. His invention was called a “Swannan” or “Swan’s Neck”.

Inventor of the Swannan-type Speed Square: John C. Swannan (1851–1928)

What Is A Speed Square Used For?

He didn’t try to make a profit off the invention or even share it with many people. He only made just enough of them for his friends and family before stopping production altogether.

Most of them were lost forever when he disappeared into the wilderness and never came back.

Luckily, before he had done that, he shared his methods with a small group of people in a small online forum.

A speed square is a very useful tool when it comes to measuring. It allows you to draw straight, parallel lines over long distances, or even around curves.

It can also be used for marking right angles. They were first made popular by the early railroad companies in the mid-1800s. It has been said that they have been in use ever since then. There are many different kinds of speed squares which can be used for many purposes.

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Most of them consist of two adjustable arms which hold a sliding ruler and a locking mechanism. Most can be used to draw straight lines, but some of the more advanced ones can also be used to draw right angles.

Lines drawn with a speed square will always be parallel no matter how much you move your arm, as long as the line is kept at the same distance away from you. This was accomplished by the curved-edge needle, which will automatically move to accommodate your movements.

How Does It Work?

The sliding ruler has multiple markings on it which can be used when making measurements or drawing straight lines or right angles. As long as the ruler is kept parallel to the ground, the distance between each line drawn will always be equal to the distance between the dots on the ruler.

When drawn at a close distance, it will reproduce the original dot or line exactly as long as there are no major bumps or uneven surfaces. If these conditions are not met, then it may not be an exact reproduction.

There are so many different types of speed squares that most people just call them all by the name “Swannan” (the company that made the first one) in order to distinguish them from each other.

How To Use A Speed Square?

Step 1: Hold the ruler with both hands, one on each side of the ruler.

Step 2: Align the dial on the back to be directly in line with a pre-measured object to be used as a guide. If you are drawing a straight edge, then make sure that the object to be used as a guide is positioned at the same distance away from you in both directions.

Step 3: Using your dominant hand only, slide the ruler along the edge of the object to be used as a guide. For straight edges, make sure that you keep the ruler at the same distance away from you at all times.

For curves, you will need to move your whole body in order to match the edge of the curving object.

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Step 4: When the ruler has made one full pass around the object to be used as a guide, move your body to the left or right until it is directly in line with the first marks drawn. Turn the dial on the back counterclockwise one click.

Then repeat Step 3. This will result in parallel lines being drawn over long distances without you really having to think about it.

Tips & Warnings

Use a pencil when using the speed square to avoid any problems with ink seeping through to the other side.

Always keep the ruler moving at all times in order to prevent breaking the line, or worse, snapping the ruler in half.

You can also use the speed square to draw right angles. In order to do this, you will need to extend one end of the ruler using a straight edge of some kind (such as a piece of wood) and then place a mark across it at 90°.

Always keep this side of the ruler in contact with the guide line at all times. As you follow the circumference of the guide line, the ruler will always be perpendicular to it. You can then use these right angles to make more precise 90° turns anywhere on the drawing surface.

If you know that you will need to be making lots of repetitive 90° turns at specific intervals, then it is best to not worry about placing a straight edge down first. Just place the 90° mark on the ruler as mentioned above, turn it so that it is directly in line with the guideline and then follow the circumference of that line for as long as you need.

This may take a little practice for you to get used to, but it can save time if done correctly.

Never use the speed square as a fly swatter.

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