Online Patternmaking Classes
by Don McCunn
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The Shoulder Strap Pattern

The shoulder-strap pattern creates a corset that extends above the bust and provides support from the shoulder. These instructions are a continuation of the procedures described for the rib cage portion of the corset in The Underbust Pattern. There are three basic steps to follow.

Top of Shoulder-Strap Wrap Shoulder-Strap Wrap
Paper Patterns Paper Patterns
Muslin Mock-Up Muslin Mock-Up

Materials and Tools

To create a Shoulder-Strap Corset you will need the following materials and tools. These instructions show how to use an, optional powernet in the side back panel to create a corset that is less restrictive than a corset that has no stretch.

Materials Tools
  • Press'n Seal (1 roll)
  • Masking tape, 3/4" & 2"
  • Pattern paper
  • Muslin (1/2 yard)
  • Powernet (1/2 yard)
  • Sewing thread
  • Rigilene boning (3 yards)
  • Eye or grommet tape (1 yard)
  • Shoe lace
  • Underwire (optional)
  • Underwire Casing (optional)
  • Basic sewing tools
  • Marking pen (optional)
  • Pencil
  • Tape measure
  • Velcro (1 yard)
  • Paper scissors
  • Fabric scissors
  • C-Thru ruler
  • Hot Knife (optional)

Create a Body Wrap

Use the steps below to create a body wrap starting from an Underbust Body Wrap. The first video for each step shows the process as a two-person operation. The second video shows it as a do-it-yourself, DIY, process.

  1. Apply Press'n Seal to the body and reinforce it with masking tape.
  2. Draw the desired design lines on the masking tape.

Applying Press'n Seal

Two-Person Mold

  1. Apply Press'n Seal to the back, over the shoulder, and under the bust to completely cover the top of the body.
  2. Cover the Press'n Seal with masking tape.

DIY Mold

Draw the Design Lines

Determining the seam lines is best done before you remove the body wrap. When this is a two person operation, you can draw in the complete design lines. When you are doing it yourself, just make marks at key reference points, then complete the lines after you have removed the body wrap.

Two Person Design Lines

  1. Draw a horizontal line at the full bust level.
  2. Extend the center front line to the above the bust level.
  3. Draw a vertical line for the apex of the bust location.
  4. Draw in the design lines for the front shoulder strap.
  5. Use an underwire to shape the corset cup seam.
  6. Draw in the center back line up to the neck.
  7. Draw in the design lines for the back, including the shoulder strap lines.
  8. Draw in a side back line.

DIY Design Marks

Create the Paper Patterns

Paper patterns will be a more stable record of the corset shapes than the Press'n Seal body wrap. After you have removed the body wrap, use the steps below to create the paper patterns.

  1. Reinforce the inside of the body wrap with masking tape as described in The Underbust Pattern.
  2. Add labels and sewing notches to each shape, then cut the body wrap along the seam lines.
  3. To create the paper patterns, transfer the shapes from the body wrap.

Label and Cut the Body Wrap

Shoulder Strap Shapes

Before you cut the body wrap, label each section and add sewing notches. The sewing notches are important because they are the most reliable fixed reference when you start to cut the body wrap apart. If you are working from a DIY body wrap, draw in complete design lines.

  1. Cut the shoulder strap shape from the full body wrap along the rib cage line.
  2. Mark a horizontal shoulder seam and add a sewing notch.
  3. Label the sections of the cup "A," "B," "C," and "D."
  4. Add sewing notches to the cup and number them.
  5. Add sewing notches to the side back seam and number them.
  6. Turn the body wrap to the inside and mark the locations of the below the bust shapes along the rib cage in the following sequence: center front, side front, center back, side back.
  7. Cut the body wrap along the seam lines.
  8. Transfer the marks from the outside of the body wrap to the inside.

Use the Body Wrap to Create Paper Patterns

The body wrap shapes can now be traced to create paper patterns. In this example the underbust shape was taken from the left side of the body. The body wrap for the shoulderstrap was taken from the right side of the body. When you trace the body wrap pieces, transfer the sewing notches from the outside of the body wrap to the inside. This process will be clearer if you have the center front and center back lines clearly marked.

The final step is to verify the length of the seam lines and add seam allowances. If you use 3/4" (18 mm) seam allowances, the seam allowances can be used as channels for 1/2" (12 mm) boning in fitting a muslin mock-up. Use 1/4" (6 mm) seam allowances for the cup.

Prepare the Pattern

  1. Trace the underbust pattern created in The Underbust Pattern on pattern paper. Leave enough room between the pieces for seam allowances. More space will be required at the top of the new pattern for the shoulder straps and more space may be required between the pattern pieces.
  2. Lay out the shoulder strap body wrap pieces matching the rib cage line of the underbust pattern.
  3. Trace the shapes of the shoulder strap wrap pieces to the top of the underbust pattern including the sewing notches.
  4. Label the pattern pieces.
  5. Add 1/4" (6 mm) seam allowances to the corset cup patterns.
  6. Add 1/2" (12 mm) seam allowances to the top of the corset.
  7. Add 3/4" (18 mm) seam allowances to all other seams.
  8. Cut out the pattern pieces.
Completed Paper Pattern
Completed Paper Pattern

Create and Fit a Muslin Mock Up

To verify that the pattern shapes are correct, create a muslin mock-up of the Shoulder-Strap Corset. For sewing the rib cage portion of the garment, including adding boning, see the instructions in The Underbust Pattern.

  1. Sew the corset.
  2. Verify the fit of the muslin mock-up.

Sew the Corset

  1. Sew the body of the corset using a 3/4" (18 mm) seam allowance.
  2. Sew the corset cups using a 1/4" seam allowance.
  3. As you sew the corset cup, press open each seam, zigzag the seam to the body of the cup, then trim the seam allowance.
  4. Sew the cup into the body of the corset.
  5. Sew the shoulder strap seam.
  6. As an option, you can sew an underwire channel on top of the cup seam allowance.
Shoulder-Strap Muslin Mock-Up
Shoulder-Strap Muslin Mock-Up

Fit the Muslin

The final step in creating the patterns is to fit the muslin mock-up. There may be little or no fitting required. During this process, you will be able to see how the fabric works on the body so that you can make refinements for any design you may wish to create.

Fit the Muslin

  1. Lace the corset.
  2. Mark any fitting adjustments you want to make.
  3. Add any desired design lines.
Front, Side, & Back of the Muslin Mock Up
Front, Side, & Back of the Muslin Mock Up

 Design Lines
Design Lines

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