Don McCunn's Blog

Pants Fitting Issues

Getting pants to fit can be a challenge. My mantra is nature never makes the same shape twice. Working with people in my online How to Make a Pants Sloper class I have had the opportunity to hone and fine tune some of the ideas in my book How to Make Sewing Patterns. The information below is intended to supplement the material in my book.

Crotch Curve
One issue that arises is that fabric in a slacks cut pants can buckle under the buttocks as I show in my book.

This is caused either by posture or the soft tissue of the buttocks going south. What we discovered by doing some field testing in my class is that this fitting issue is actually reflected in measurements.

When I was researching pants patterns the crotch curve never dropped lower than the top of the inseam. This means that when you add the Crotch Depth and Inseam measurements they will equal the Waist to Floor measurement.

But in some bodies the buttocks can be lower than the ideal location for the top of the inseam. In this case the Inseam measurement indicates the length of the inseam and the Crotch Depth indicates how much the back crotch curve needs to be lowered for an appropriate fit. I have written and illustrated this relationship in a little more detail in a Crotch Curve PDF file you are welcome to download.

Adjusting for Tummies
Another fitting issue that we have addressed in my class is how to optimize the fit of pants for women with tummies. I am grateful for the assistance that Barbara Cleary provided in field testing a new measurement and giving me permission to use pictures of her journey addressing this issue.

Once again in my book I indicated how to adjust for tummies on page 40. The concept is to extend the front crotch curve so the pants don’t pull in tightly directly under the tummy as you can see in the “before” photo on the left. What Barbara and I worked out is how to use a Tummy Width measurement to establish how much the front crotch curve needs to be extended so the pants will not pull in here, the photo on the right. Here is a link to the Optimizing for Tummies PDF file you can download.

Caveat: beware of relying too much on the measurements. The only way to really evaluate pattern shapes is in a fitting. Use these measurement ideas only as an initial guide.

Sway Back Posture

One of the fitting issues that has come up in my online class How to Make a Lower Torso Sloper is the sway back posture which some refer to as a “tilted waist.” If a body has this posture, it can affect the fit of any pair of pants or skirt you buy or make. These garments “hang” when the hips are larger than the waist. If the waist is larger than the hips, then the skirt or pants have nothing to hold them up–except suspenders.

The tummy affects the fit of the front and can be larger than the hips. It is the shaping of the back pattern from side seam to center back that the sway back fit addresses. It is a common posture configuration for many women. If the fit of the back and sides is correct for a particular body, this portion of the garment may also hold up the front even if there is a tummy. Only creating an accurate fit for a specific body will you know whether this will work.

If you look at the picture below you will see how this person’s sway back is flat from the natural waist to about 2″ down toward the hips. If the top of the waistband is low enough, the sway back will not affect the fit. But if the waistband is within the range of this flat area of the back and the dart is not shaped accordingly, the garment will tend to slide down and hang unevenly. This shaping is also important for the Contoured Waistband which I describe in another blog topic.

It is my experience that the best way to create a sloper that fits accurately is to align the grain of the fabric to the contours of the body keeping the horizontal grain parallel to the floor and the vertical grain at right angles to the floor. For a sway back posture this means that the top of the hip dart will be parallel or almost parallel where the back is flat, then angle out to the fullest part of the hip at the bottom of the sway back contour.

This posture will also affect the fit of any dress, coat, or jacket that is shaped to fit the back.

Adjusting the Sleevecap and Armscye

My current thinking about sleeve caps is a little different from what I have in my book How to Make Sewing Patterns. I have used the approach I described in my book for a long time. But since I have been teaching my Online Classes, I have had some additional thoughts and observations which I want to share.

Background First:
The reason for ease in sleeve caps is a little different than the reason for ease in other parts of the slopers. A minimum fitting ease is added so you can move comfortably in a garment. If your design calls for additional fullness beyond the basic comfort factor, this is design ease.

The ease in the sleeve cap is to adjust the fabric of the sleeve so it can be shaped over the shoulder. This ease, unlike other ease factors, can be referred to as “sewing ease.” The sleevecap needs to be worked into the armscye (aka armhole) during the sewing process. I show why this is required in more detail in my blog entry “Sleeve Caps – The Reason for Ease.”

When I was researching my book I found the sewing ease that seems to be not only a “standard” but something that actually works on most bodies is to add 3/8″ of ease to both the front and back of the sleeve cap making the total sleevecap 3/4″ larger than the armscye, see page 74 of my book.

Always Fit the Bodice First:
Before you start to develop a sleeve sloper you need to have the fit of the armscye worked out for the upper torso (aka Bodice).

Adjusting Side Seam and Underarm Ease:
Once you have drafted the sleeve as I show in my book you need to verify that the length of the sleeve cap has the necessary sewing ease as described above. It has been my experience that for a lot of bodies, the sleeve cap drafts very close to the appropriate length. I show how to make any necessary adjustments on page 73.

Caveat: After listening to the issues of the people in my online classes it has occurred to me that the “standards” of ease for the bodice and sleeve may not be appropriate for the proportions of some bodies. It may be possible that some people have a smaller or larger arm than is accommodated by standard ease measurements. If this is the case, ignore the “standards” of 4″ of ease for the bodice and 3″ for the sleeve. Adjust your sleeve cap or bodice to which ever is the largest length required, see Figure 150 on page 73.

Use the following steps to create a fitting shell to determine if you have the correct amount of ease for the comfort and fit you want.

Marking for DIY Fittings

Back in the 1970s I wrote in my book How to Make Sewing Patterns about how you could fit yourself using typewriter ribbon to mark those hard to reach places. Who would know back then that typewriter ribbon would become so hard to obtain.

Fortunately I have found a product that works as a wonderful substitute for typewriter ribbon. It is called Chaco Liner from Clover Products. This product comes in a dispenser that allows you to draw lines on fabric using a device with a spoked wheel. The video below shows how to use the Chaco Liner Refill to mark the hard to reach locations such as the top of back darts and seams like the neck curve.

How to Make Sewing Patterns — book update

I wrote my book, How to Make Sewing Patterns, back in 1977 and have been asked if I had plans to revise it. There are only two things I do differently today than when I wrote the book 33 years ago. So I am focusing my time on teaching my online Patternmaking Classes and developing supplemental material to my book as Pattern Design Guides rather than taking the time to revise the existing book.

The two things I do differently are I use gingham for fitting the bodice and skirt. And I have revised how I draft the woman’s front bodice pattern.

Gingham for Fitting:
When I was teaching Pattern Design at San Francisco Community College Adult Education Division back in the 70s I would stress the importance of looking at the grain of the fabric to determine whether the fit was correct. As we were using muslin, I would carry around a magnifying glass so that people could clearly identify the direction of the grain.

Then one day I was in the fabric store. When I walked past the display of gingham, I did a double take. The woven pattern of the different colors of threads in the gingham made the grain jump out. It was so easy to see what was happening to the grain as it is shaped on the three-dimensional human body I knew I had found the perfect fabric to achieve super accurate fittings. When I teach my online Upper Torso Sloper (aka Bodice) and Lower Torso Sloper (aka Skirt) classes I can use student submitted photos to help them achieve accurate fits within an 1/8″.

Woman’s Front Bodice Pattern:
Throughout my book I show how to draft the initial patterns without any darts. I do this because nature never repeats the same shape twice. So it is my contention you will never be able to determine the size, location, or length of darts accurately from measurements. If there were corners and sharp angles in the human body, maybe you could take accurate measurements. But the human body is a series of continuously changing contours. From what I have heard even body scans using sophisticated equipment cannot accurately create a two dimensional representation of an individual’s body from the measurements they take.

The one exception to “no darts” in my book is that I show how to draft a woman’s front using a dart. Once again when I was teaching back in the 70s I had large class sizes and lots of bodies who were willing to helping me develop data. So I came up with a chart for how to adjust the woman’s bodice pattern based on the difference between the full bust and above bust measurements.

But the chart does not cover the full range of possible bust sizes. But more than that, it creates a pattern that has a bust to waist side panel that is tricky to design from. It is essentially off grain. So what I do now is draft the woman’s front pattern without a dart. It creates the size you need so that you can establish a very accurate dart in a fitting.

I have a PDF file with the two revised pages for this draft which you can download and print out to revise the drafting procedure in my book: Women’s Front Bodice Pattern Draft.

To fit this pattern I use a dart into the armscye for the above the bust shape, the “A” Dart, and a dart to the waist to establish the below the bust shape, the “B” Dart. What this fitting procedure does is it allows you to use the horizontal grain around the full bust to create a very accurate “A” dart. You can then adjust the “B” dart to ensure that the vertical grain of the fabric is correct at both the center front and on the side of the body.

With the sloper designed in this way, whatever design lines you draw for the side of the body can be envisioned as they relate to the horizontal grain.