To Get the Right Armhole, Fit the Bodice
There's more to fitting an armhole, also known as an armscye, than you may think-it requires fitting the bust dart, shoulders, and side seams. And the only way I know to successfully fit an armhole is to use a muslin. For more information on armhole fittings be sure to pick up Threads #117, and don't miss other techniques like this one by ordering a print subscription which comes with FREE access to our tablet editions.
People with identical bust and over-bust measurements often fit into the same size and style pattern differently (see Same measurements, very different figures). The shape of your body depends on where you carry your flesh and dictates the shape of an armhole. A muslin is the testing ground-it's the perfect place to sort out fit issues.
Same measurements, very different figures
A muslin is a test garment in inexpensive fabric, initially sewn without facings or edge finishes. You pin-fit the muslin right on the body. The object is to make the fabric skim the body with no signs of wrinkles or strain lines. Although becoming a fitting expert can take years of practice, I'm going to give you a straightforward method of how to fit an armhole and develop a well-fitting bodice muslin that accurately reflects the shape of the body.
Follow this order when fitting: bust, back, underarm, shoulder seam placement and slope, shoulder point to underarm, and side seams. Then adjust the pattern tissue using the fitted muslin as your guide. Such a completed pattern can be used as a reference to position darts and establish the armhole shape in future patterns. You'll end up with a perfect pattern for a closely-fitting bodice with or without set-in fitted sleeves. Just because fitting can be complicated, don't let it scare you away.
Glossary of terms
|Use this glossary to help navigate your pattern and understand the fitting process and the terms used in this article. Key landmarks are identified on these pattern pieces. The dotted lines indicate possible fitting sites.|
You'll need a person, a pattern, and some woven fabric
|Don't try to fit a too-small pattern. A strain between bust points means you need a larger pattern. See Choose the Correct Pattern Size.|
Select a fitted blouse pattern intended for woven fabrics that includes bust darts in the side seam or armscye. (See above Glossary of terms for an overview of the pattern areas that will be need adjustment.) Make sure the finished bust measurement printed on the pattern is between 1-1/2 and 2-1/2 inches greater than your actual full bust measurement to allow enough wearing ease (wearing ease is the difference between your body's measurements and the finished garment's measurements, which is necessary so you can move in the garment). Use a stable woven fabric without spandex, and follow the pattern to make your sleeveless, collarless muslin. Sew your seams using a long machine stitch, and use a thread color that contrasts with the muslin fabric so that you can easily see to clip and release seams during fitting .
You'll need an assistant for the fitting process. Consider hiring a dressmaker to help you. Plan on making several muslins to get the right fit; the results are well worth the effort. If you've never made a one, watch this video to learn how to make and and use a muslin.
A muslin tells you more than your measurements alone do
The first muslin serves as the rough draft for blocking out the major fitting changes. I always make at least one additional muslin to check my first fitting results. If you're a beginner, it's better to make more muslins with fewer changes to each than to try too many changes at once.
Don't try fitting a muslin that's a size too small because the tightness distorts the overall fit. For example, if you get a strain line between the bust points (drawing above right), start over using a larger size pattern.