# How to use the humble L-square or tailor’s ruler

Nearly everyone has an L-Square made by Fairgate, sometimes called a tailor’s square or rule for pattern drafting; these are indispensable. Today I’d planned to tell you all about the various uses of them but time has a way of catching up with me. Instead, I’ll tell you about them in the context in which the subject came up. Below is a drawing of one. The typical square is 14″ X 24″ making them difficult to photograph. A larger view is here.

The question was:

I was wondering what is the best way to make half scale patterns. Should I only draft half of every measurement when doing a basic block? If I have a measurement of 14″ the ruler will break it down to 7″?

The answer is yes. The ruler has a built in math cheat sheet. Below are some of the scales marked off. The ruler also breaks down into 6ths and 12ths on the long arm and 8ths and 16ths on the short arm. See below if not from here.

To easily draw only half of 14, you draw from the zero point, up to the 14 on the halves portion of the scale. This will equal 7″ as shown below.

See, it’s very simple to cheat on figuring measures with your L-square.

Now maybe when I have more time, I can explain how this tool is used with archaic pattern books to draft patterns. For example, if you’ve ever read the texts of these older books (meaning before 1960), you’ll see frequent directions to draw a line that is 1/6th of breast or something similar. This would mean to draw a length from zero up the number on the scale of 6ths that represents your chest. Nifty, huh?