What’s better than one pattern size? A variety of sizes that fit a variety of body types. Pattern grading puts you in the driver’s seat, giving you the ability to adjust the sizing of a pattern while keeping the garment and its features intact. We’re going to start off with the basics by learning how to grade a basic bodice. Grading isn’t so bad, let us show you – let’s get started!
Note: This is lesson 5 in our Beginner Draping and Patternmaking series, so be sure to check out all the tutorials and videos!
Prep Your Work Space
Purchase tools we use:
- Fabric Shears
- Marking Pen or Marker
- Clear Tape
- Measuring Tape
- Pattern needing to be graded
*The following example will use the cut-and-spread method with even grading for a basic bodice. The cut-and-spread method is the simplest method to use and an even grade is much easier to calculate than an uneven grade, this is why we are starting here. It is best to start with a simple base pattern and work your way up as you get more comfortable with grading. You should begin grading with a basic pattern, today we will be using a basic bodice, which you can learn how to drape on your own here!*
Establishing a Grade
Record basic measurements of your desired bust, waist, hips, and the measurements of the base size of the pattern you want to grade. So, essentially, you are gathering the difference between the pattern measurements and your body’s measurements.
In this example of even grading each category has a difference of 2” which makes the OVERALL grade an even 2”.
Calculate the Allocated Grade
The formula is simple:
X(your grade)/4=allocated grade
Our example is as follows:
Divide Allocated Grade to All Pattern Cut Lines
The illustrations on the right side show the horizontal and vertical cut lines, which are the main areas where bodies differ in size for grading a basic front and back bodice.
Note: Cut lines should not vertically intersect through darts, this would change the pattern size. The images to the right show what the pieces should generally look like once they are spread apart using the calculation just covered above.
**We will be using a “commonly used” grading chart for reference***
Our overall grade was 2” so we will follow the reference chart above to get the numbers we need below.
- 1 & 6 —-> ⅛
- 2 & 7 —-> ⅛
- 3 & 8 —-> ¼
- 4 & 9 —-> ⅛
- 5 & 10 —-> ⅛
Clean Up Your New Pattern
Using the amounts calculated above, slash along all the cut lines and spread (if you need to make the pattern larger) or overlap (if you need to make the pattern smaller).
Blend any gaps that you gained from spreading (if you had to overlap, then split the difference evenly).
Use clean paper to trace the graded pieces, transferring all marks including the grainline and notches.
Gift yourself the freedom to make the most out of paper patterns by extending the sample size to work best for your vision. Pattern grading takes the sample size and turns it into a range that’s more fitting for everyone. It only takes a little extra time while resulting in an outcome that’s definitely worth the extra work. With the power that pattern grading gives you, you’ll be able to make that jacket of yours that your friend is always raving about even if you aren’t the same size!
What type of pattern are you looking to grade first? Leave any questions or comments below!
I just want to say thank you for having the coolest sewing site. I am in love with your patterns and will follow your blog always.
These are great instructions and the grading chart is very helpful. But did you mean to call this “Beginner Grading”? This is flat pattern alteration, not draping.
Hi, Donna! This is lesson 5 in a series that began by draping a basic bodice. 🙂