Then, measure the line so you can make the other sides of the square the same length. Set squares are only accurate if they are used along with a T-square. Set squares are often used in combination with a T-square to draw more accurate angles. A right angle is the standard by which all carpenters build. Dr. Butler received his PhD in General Physics in 2004. Note that you can draw a 90° angle at either end of line segment AB if you want to (in other words at point A or point B). All set squares offer three drawing surfaces or planes representing three different angles which always include one right angle. Constructing 75, 105, 120, 135, 150 degree angles and more. Point A (or point B) would serve as point O in the above instructions. Common errors when using T-squares and set squares are More commonly the set square bears the … Set up a piece of A4 paper on a drawing board using a google_ad_height = 15; google_ad_client = "pub-1698037631606045"; Your guide leg should be running across the board at either a 90- or 45-degree angle, depending on the cut you need to make. In order to draw a 30 degrees first you will have to draw a 60 degree and bisect the 30 degree angle. See drawing e-1. It has a measure of 90 degrees. Next, draw a line going straight up from each end of the first line that are the same length as the first line. If it measures 5 units, your corner is square. Technology Student states that set squares can only be accurate when they are used in combination with T-squares.