3 Pattern Making Conventions

Creating a Mock-up

The mock-up is a very important step in the creation of a custom garment. The mock-up (also referred to as a muslin or toile) fulfills these important requirements:

• It allows the pattern maker to see and correct any fitting problems before cutting the garment out of expensive fabric.
• It allows the designer to make changes that will create a more flattering or appropriate garment.
• After you have fit the sloper mock-up you can correct the basic sloper pattern.
• Any patterns you create from the corrected sloper should fit very well.

Whenever possible, it is best to make the mock-up out of fabric similar to that being used for the actual garment. This is especially important in the case of stretch fabrics or bias cut garments. It does little good to make the sample for a leotard out of a firmly woven cotton. Avoid using fabric that has a vibrant print as this may make it hard to see the details of the garment.

It is important to leave large seam allowances in the try-on garment. At least one inch of seam allowance will allow you some room for alteration.  A useful technique is to trace around a pattern that does not include seam allowance with a pencil. This method may seem to take longer than folding the fabric and cutting double, but it has these advantages:

• You can use the pencil lines to pin and stitch accurately.
• You can redraw if the pieces don’t quite fit onto the fabric .
• It is easier to use of every bit of fabric
• Alterations are accurate because you can measure from your original line.
• You are able to leave much larger seam allowances.

Use weights or push pins (if you have a table with a pinnable surface) to hold the pattern down while you trace it.  Once the pattern is traced, you can add seam allowance (it is easiest to remove the pattern before adding the seam allowance). One of the advantages of this technique is that you can add different amounts of seam allowances to different seams. Add the most seam allowance to areas that might change.

Here are some good seam allowance widths for a mock-up:
• 2” (5.08 cm) at all hems (sleeve, skirt, trousers, jacket, etc.)
• 2” (5.08 cm) at closures whether the garment closes in the front or back.
• 1 1/2” (3.81 cm) at side seams. Depending upon the curves involved, you might need to clip the curves once the model has tried the garment on and you see that you will not have to let it out.
• 1” (2.54 cm) at armholes. Again, you may need to clip here once you are sure you do not have to move the sleeves.
• The rest of the seams are at 1” – 3/4” (2.54 – 2 cm) depending upon the possibility of alteration.
Remember that the seam allowances do not need to be exact since you have the stitching line drawn on the fabric.

When sewing the garment together, it is most accurate to pin along the seam lines and take the pins out as you sew. It is possible to cross pin although that tends not to be as accurate.
This technique takes some practice to master, but the effort is well worth while. You can accurately pin the pieces together at the balance marks and the upper and lower edges.

Mock-up Tips

As you use mock-ups as a fitting tool, you will develop your own methods to create the most useful garment. Here are some things I have found useful:
• Always machine (or hand) baste your mock-up together. This makes it very easy to rip open a seam to fit the garment properly.
• Use a tracing wheel and tracing paper to trace finish lines through to the outside (hems, necklines, closures).
• Use an extremely large hand baste to baste up hemlines so you can see the estimated length. The very large stitches will allow you to take the hem down quickly.
• Do not sew the mock-up together with contrasting thread. You want to see the garment, not at your stitching.