Introduction: Draft a Custom Bodice Sloper!

About: I'm currently in college studying everything I can. I work in a makerspace where I've really been able to grow a lot. Keep an eye out for new Instructables on the way! Thanks for checking out my page!

Have you ever wanted to make a costume or outfit but just couldn't find the right pattern? Or maybe you're tall like me and the pattern doesn't come in your size? Sometimes you can find a pattern that's sorta right, but that could cost you $30+. I always found myself wishing that there was more information on the internet to teach me but it was always behind a paywall or I would find some instruction but it would be incomplete. As someone who believes in, (and thrives on,) freedom of knowledge and information this was... very frustrating. So I spent a few years taking classes, I paid for the tutorials, and I did a fair bit of failing up to bring you the first in this series of pattern making tutorials. I hope this can erase some of the designing world's barriers to entry.

What is a sloper? A sloper is the basic building block used to make flat sewing patterns. They're sort of like patterns except they have no seam allowances and are very fitted. Once you draft one of these you can do quick alterations to make any kind of garment you want, from shirts and dresses to jackets and costume pieces.

Today we're making a bodice sloper for woven fabrics with little to no stretch, meaning a sloper with darts. (Darts are triangles cut into patterns which allow the garment to account for curves.) Because there are so many steps you might be intimidated by this Instructable, but don't be! It's all done with the same basic math and all it takes is a little patience.

If you're planning on working with stretchy fabrics like jersey knit or spandex, this probably isn't the best bodice sloper for you. Keep an eye out for my coming Instructables which will be sleeves, pants, and slopers for stretch fabrics.


You will need:

  • A measuing tape
  • Clear ruler or quilting squares
  • A pencil
  • A roll of paper, (the backside of wrapping paper works wonderfully.)
  • A hip curve ruler, (you can print one online.)
  • French curves, (you can also print these.)

Step 1: Taking Your Measurements

If you're using your own measurements, it's better to have someone help you. You want to take them while standing naturally, wearing very fitted clothes. If you wear a bra it's a good idea to wear the size you normally wear out. When measuring circumference make sure to keep the tape parallel to the ground for an accurate reading.

The measurements you will need are:

  • Bodice length: Traditionally this is from the point where the shoulder meets the neck to the hip line. You can, of course alter this to make your garment longer or shorter but for the sloper we're going to stick with the standard.
  • From shoulder to shoulder.
  • Circumference of your waist. (The smallest part of your torso.)
  • Circumference of your bust. (The largest part of your torso.)
  • Circumference of your hips.
  • Distance from the shoulder line to the bust line.
  • Distance from the bust line to the waist line.
  • Neck width: This can be measured by draping a string around your neck and measuring the distance between the lengths as shown in the photo above.
  • Neck depth: This one varies by designer but we're just going to use the standard 3".
  • Distance in between bust points: (Generally this is the distance from nipple to nipple.)

Write all of these measurements down for use later.

Step 2: Plotting Your Lines

The first major step in drafting this sloper is to plot the lines for the hip, waist, bust, and shoulders. Since my paper is perfectly straight I used the bottom as my hip line. If yours is not straight simply use your ruler to draw a long line at 90 degrees from the edge of your paper. From the hip line take your bodice length and mark that value above your hip line. For instance my bodice length was 24" so I made a mark 24" above my hip line. From that point mark down the distance from your shoulder to your bust, then from your bust to your waist. Draw lines for those as shown.

Step 3: ​Drafting Your Front Neckline

To draft the front neckline, divide your neck width by 2. Since my neck width was 5" I'm measuring 2.5" from the edge on my horizontal shoulder line. Then use the standard 3" neck depth to measure down from the shoulder line and create a rectangle as shown. Draw a diagonal line from the top left corner of the rectangle to the bottom right.

Measure the length of your diagonal line and divide that measurement by 3. Mark the product of that division, (mine was 1.333") up on the diagonal line from the bottom right of the diagonal, essentially splitting the line into 2/3rd and 1/3rd pieces. This mark will serve as the curve guide for the neckline. Manipulate your french curve until it touches all three of the points and trace the curve.

Step 4: Shoulder Slope and Armhole Depth

For the shoulders, divide the measurement of the distance between your shoulder ridges by 2 and mark that from the edge of your paper on your shoulder line. From that mark, measure down an inch, then connect that mark with the edge of your neckline as shown.

For the armhole depth you could do a crazy complicated method of measuring your armhole and trying to calculate the fit allowance but it's much easier just to use this simple formula:

(Bust circumference/4)+1.5"

When I do this formula I come out with 8.625". Measure your armhole depth down from the end of your shoulder slope as shown and draw a straight line down. (you can see I overshot my mark by a bit. Then, using the same mark as a guide, draw another straight line out from the edge of the paper. This will be your high bust line.

Step 5: Creating the Dart

This is an important step to ensure that the patterns you draft using this sloper produce garments that fit correctly and contour to curves. the first thing to do is to divide the distance between your bust point by two and mark that from the edge of the paper onto your bust, waist, and hip lines, then draw a line straight up and down connecting these points. For this sloper we're going to use the standard 1.5" dart allowance so divide that by 2, (.075",) and mark that on either side from where the vertical line you just drew intersects the horizontal waist line. Use those points to create a diamond shape as shown.

Step 6: Finishing the Armhole and the Edge

Earlier you drew a line from the end of the shoulder slope to the high bust line. Divide that line in two and mark the halfway point. Then make a mark an inch behind it. Again you're going to connect the three points with your largest french curve.

The last step for the front bodice is to do these formulas:

  • (Bust/2)+0.5" fit allowance.
  • (Waist/2)+0.5" fit allowance+1.25" dart allowance.
  • (Hip/2)+0.5" fit allowance.

Mark the products of these formulas from the edge on their respective lines. Use your hip curve to connect these points as shown and viola! You have a custom front bodice!

Step 7: Back Bodice

The good news is that the back bodice is almost exactly the same with two small differences. You will follow the exact same steps except the back neckline will be 2" deep instead of 3" and the back armhole will be pulled 2" back instead of 1" as shown.

I hope you have fun making... well, whatever you chose to make with this sloper! If you have any questions feel free to ask me in the comments, I usually respond within the hour. Keep an eye out for the next in my series of sloper Instructables: Drafting a sleeve sloper!

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