A what ?!? Today, I suggest we talk about the Japanese ruler, which is one of the most valuable tools for someone making or modifying patterns. And if you think of yourself of someone that uses only already made patterns, do not run away yet, because you will see that in reality, a Japanese ruler it’s practical for all the dressmakers in the world: amateur or professional!
So let’s talk a little about the Japanese ruler.
What is a Japanese ruler?
It is a flexible plastic ruler that is 50 cm long (in the vast majority of cases) by 5 cm wide. It is transparent with the measurement traces in red. There are a lot of lines that can be scary and yet it is ULTRA practical!
In fact, you will find a classic graduation 50 cm long and 5 cm wide. Every centimeter is marked with a thick red line. You will then find a slightly thinner line every 5 mm, then an even finer line every millimeter. The lines are present along the length.
In width, we find the traces of centimeters and only a few millimeters at the start of the ruler. There is also a built-in protractor at the center of the rule.
All these indications might seem a bit too much, but they are really very practical and, once you know how to use the ruler, you will no longer find it “weird” and you will think of it as your BFF (best friend for life)! Indeed, once I have used one, I realized that it saves me an incredible amount of time compared to a classic ruler.
Let’s see how to use this still strange tool, shall we?
How To Use a Japanese Ruler
Make clean squares
This is its least important use, but when we do not have a square handy, its grid is very practical and allows you to draw right angles. Be careful, we use it for small squares (short lines), if you have to create a square which will be 1m long, I advise you to use a large architect’s square.
Find the bias direction of a fabric
Ah, to make your bias have exactly the same connection, it’s neat, isn’t it? But to succeed with your bias, you have to … tadammmmmmmmm … cut PILE across the bias!
As a reminder, bias is the most “elastic” sense of a warp & weft fabric (non-elastic due to its weaving). Back to the Japanese ruler. If you need to cut a pattern piece at an angle, put your ruler on a line that is in the direction of the chain (if it is a pattern already made on the straight grain line, if you are making a bias pattern on paper on the side line of the rectangle).
Once the ruler is in place, look at the middle of your ruler, there are lines that start at 45 ° from your square lines. You just found the skew lines. Place a guide on each side of the line and ruler, then draw your bias line.
If you are directly on the fabric, find the warp direction of the fabric (take a good look at the weaving, these are your threads parallel to the edge of the fabric). Lay the ruler on these wires parallel to the selvage, then use the 45 ° marks on the ruler to find the bias direction.
Measure your roundings efficiently
When you want to adjust a pattern or just check a measurement, sometimes you need to measure the rounded parts. You might be tempted to do it with a tape measure. But since it is very flexible, it will slip and you will end up with an absolutely unreliable measurement.
I often prefer the Japanese ruler or a small metal ruler (which is 1 cm wide) for this mission which requires precision. The Japanese ruler being flexible, it can completely ensure the mission and this saves you from having to own: a Japanese ruler + a protractor (for the previous mission) + a square + 1 metal ruler if the seam is only a hobby for you!
Set the seam allowances
Finally, we come to mission number 1 of the Japanese ruler in sewing! If you are creating a pattern (for example of a small pocket), I advise you to use the ruler to apply for the seam allowances.
As it is graduated over 1 cm (and more), it allows the value to be set very quickly, whether in a straight line or in (or?) Rounding!
And if you do not create patterns, it will also be useful for the hem values! Indeed, you will first need to know the final length of your skirt, dress, pants, or any other model, then transfer this length to the pattern without forgetting to add the hem (most patterns explain it to you).
With a Japanese ruler, you save time because it is 5 cm wide with the lines on every centimeter. You will just have to place the finish line under the ruler to the measurement that interests you (example if the hem is 3 cm then I place the finish line on 3 cm and I trace on the edge of my ruler and my hem is created).
Where can I find a Japanese ruler?
Finding a Japanese Ruler it’s not always the easiest mission! As a student, I bought it directly at school (oh yes, know that after a few years, it can break and above all, above all, never use it on the ironing board because it can melt! RIP rule no. 1).
Today, I melted the first rule, the second broke after 10 years of service and there … well, I struggled to find a rule. There are not a lot of shops that offer them or at terrifying prices (hello the rule at 50 dollars…). We may be tempted to look on Ali Express except that… we often receive it in Chinese or Japanese, which is not really helpful!
Luckily, I found some really good ones on Amazon, and now I always buy in bulk to just be on the safe side!