April 09, 2015

Grading from body measurements pt. 1

Pattern grading is the process by which new sizes are developed from an existing pattern. There are various methods or processes used to grade a pattern. These methods include slash-and-spread, shifting, and CAD. At the end of the day, each method accomplishes the same thing, a new size.

The apparel industry has received a lot of criticism for their sizing, especially of women's clothing. At it's core, sizing goes hand-in-hand with pattern grading. You have to define your sizes in order to grade a pattern. In order to grade a pattern you have to know body measurements for each size. The common grade rules for women's apparel is the 1", 1.5" and 2" grade rules used in the United States. Similar grade rules are found in Europe and the UK. The primary criticism is that these grade rules are not based on anthropometric data, or actual body measurements. Instead these grade rules are just pulled out of a hat without regard to women or their fitting needs. These arbitrary grade rules are merely for the convenience of industry.

This is the point of view taken by N. A. Schofield in her article Pattern Grading found in the Sizing in Clothing book. The goal of her research was to test the idea of creating grade rules based on actual body measurements rather than an arbitrary grade rule. There has been a lot of criticism of the industry over sizing and it is a worthy goal to research alternatives. Asking the why questions. Why does the apparel industry do things the way they do? Why do we grade women's clothing this way? Can we do it differently? I've asked a lot of these same questions as I've looked at children's clothing. When I started out, I didn't understand the why and sometimes the answer was not satisfying. I can totally get behind Schofield's motivation to try and find an answer.

And yet, I feel like I am setting up to be very critical of Schofield's research and I don't want to give the impression, as an industry professional, that even asking the questions were wrong. She was right to ask the question and to test an alternative. The results of her research are interesting and ironically (and indirectly) add support to current practices.

So here are some of Schofield's main arguments:

1. 1", 1.5", and 2" grade rules are not based on anthropometric data. Meaning it is not based on body measurements or the proportional relationships between body parts/areas. These grade rules were intended for the convenience and ease of hand grading.

2. Grade rules should be derived from body measurements. This means that grade breaks between bust, waist, and hips should not be consistent. Instead of a 34-36-38 chest measurement, we should be seeing a 34-35.5-38 (just as an example), chest measurement.

3. Size prediction and also body measurement prediction needs refinement. This idea is rather complex. Body measurement studies create a lot of raw data. In order to make sense of it, statisticians will test size prediction by using one or two body measurements. So can you predict the overall body size by using just the height or chest measurement? And if you do that, what influence does that have on other body measurements? If a person gets taller, do they also get wider? It is a complex question and not easily answered because there are so many variables. Statisticians bring order to raw measurement data so that we can organize the body measurements into sizes. They do this by averaging and, in some cases, normalizing the data so we can work with it easily. Schofield implies that we should just rely on the raw measurement data.

The ultimate goal of this study was to improve overall fit of women's apparel by basing grade rules on actual body measurements. I'll have to break up my review of this study into multiple blog entries because I have a lot to say about it. So stay tuned.

March 19, 2015

Production Systems, Sizing, and Quality Control

Having worked in the apparel industry for a while now, I sometimes have to take a step back to see how much goes into the design, production and selling of just one item. The goal is to work out all of the bugs before an item goes into production. Still, things can and do go wrong and those things can affect the size of an item. Where can things go wrong?

1. Pattern making and grading


A poor pattern or poor grading certainly affects the size. Inadequate seam allowances, missing notches. There are a lot of little things that can go wrong, though if you read the rest of the list, you can see there are a lot of other areas that can cause problems.

2. Marking


Marking is the process of laying pieces out in preparation for cutting. Many markers are now made by computer, some automatically. There are various setting that allow the marker maker to bump pieces closer together, tilt, or rotate pieces. Each of these options can affect the final outcome, so they must be used rarely.

3. Spreading


Spreading is the process of laying fabric on a cutting table in layers. Certain fabrics stretch during this process and need a certain amount of time to relax. If the style is cut without the fabric being allowed to relax, then the pieces will relax after being cut and the item will end up too small. Layers can also shift and move.

4. Cutting


Accurate cutting is the only way to ensure the item ends up as intended.

5. Sewing


Taking too big or too small of a seam allowance affects a size. Seam allowances should allow a cut off allowance because nearly all operators trim off a little bit.

6. Finishing


Finishing includes steaming or ironing. Too hot a temperature can shrink an item.

These problems can be minimized by implementing systems and policies during each phase of development and production. One company I worked for had a quality audit system that checked each step of production. Anything that had finally made it to production had been perfected, for the most part. There was that one style that shared patterns with another style. A problem came up in production where the obvious solution was to make a new pattern for the new fabric, but that never happened. Production just had to deal with it. But those situations are rare.

In any event, systems (procedures/policies) have to be implemented for development, production, and finishing to catch problems before the item is shipped to the customer..

This blog entry was inspired by the article Production systems, garment specifications, and sizing by S. P. Ashdown, L. M. Lyman-Clark, J. Smith, and S. Loker in the book Sizing in Clothing.

March 10, 2015

A t-shirt refashion maybe

I picked up this t-shirt on clearance at Wal-mart. The embroidery caught my attention and at only $5 it was worth taking a chance. The style is meant to be loose, so the t-shirt itself is boxy. There is a drawstring casing at the high hip level to cinch it in. I did get compliments when wearing this, but it was not comfortable. The fit was just too sloppy for my tastes.

So I pulled out my TNT t-shirt pattern that I made a few years ago. My initial thought was to just cut down the shirt to match the fit of my pattern. Essentially using the t-shirt as a fabric rather than a shirt.

There are a few problems that stopped me. First is the casing. I debated on cutting out the casing and just having a band on the bottom hem but I was concerned the seam would be in a weird place. The next problem was the sleeve. There really isn't enough fabric to recut the sleeve.

Looking now at the picture, I wonder if I should take in the sides and call it good? What do you think?

March 05, 2015

Communicating size and fit through size labels and charts

The primary way most clothing brands communicate size information is through a size label. This works in most retail settings. Online (and print catalog) clothes shopping adds the benefit of including an easy to use, sometimes interactive size chart. Additional instructions on how to measure yourself is also helpful.

Pictogram showing body dimensions for a specific size
A pictogram showing body
dimensions for a specific size.
None of these solutions are completely fool proof. First, the manufacturer interprets and adapts measurement data to meet the needs of their identified customer. This means they have created and implemented a size system in anticipation of what their customer wants. But a customer may want something to be closer/looser fitting, and shorter/longer lengths than the manufacturer. How does one balance size and fit for a diverse population with ever shifting expectations?

The current trend among new fashion companies is to design for a very narrow customer profile. By targeting a very specific customer, the manufacturers can optimize the fit of their brand to their customer. Larger big box brands have to fit a wide range of body shapes and sizes and their clothes will never fit as well as a more exclusive brand. In some cases a manufacturer will modify their sizes for an existing size system, so that they change what a size means for their target market. In other words, a size 8 for one brand will mean something entirely different for another. This is why there is so much variation in the marketplace between brands.

On the surface this sounds like vanity sizing run amok. If manufacturers change the underlying sizes to fit their version of a size, then surely they are deceiving us into believing we are a smaller size than we truly are. Truth in advertising and all that, right?

The problem with only one size standard across brands is that it does not allow for variation. Women in particular have a large variety of body shapes and sizes. Because manufacturers are free to adapt to meet the needs of their customers having multiple versions of a size will allow people to find the version that fits them best. Once they do, and if the styling is right, they will become loyal customers.

The problem comes back to how to communicate that to the customer. As I said at top, providing more information helps the customer to make a more informed choice. And that is the true challenge.

*This blog entry is part of my on going review of Sizing in Clothing, and is a discussion inspired by the article, Communication of sizing and fit by J. Chun. This article goes into a little more depth about how sizes have evolved and what they might mean.

February 10, 2015

Size standardization for clothing

In academic circles there is the idea that we need one measurement and sizing standard to solve all our fitting problems. A top down approach with no allowance for variation. Customers often complain that manufacturers have no idea what they are doing because nothing ever fits. Manufacturers face an enormous challenge in trying to interpret size specifications while at the same time meeting the needs of their customers. The more I read about sizing the more chaotic it seems. At the end of the day there is more than one way to look at size standardization, and I think only one battle to fight.

One standard to rule them all

Yes, the idea that one standard can be established for everyone. By forcing compliance we will have peace on earth, and yes, our clothes will fit! Considering the variety of shapes and sizes in the United States alone, the idea is really a fantasy.

  • One standard guarantees that some of the population will not have any clothes that fit. One could argue this situation exists today, so why not try one standard. With no allowance to adapt to fit the wide range of shapes and sizes, then outliers will never have clothes that fit.
  • Our population is constantly changing. The most recent sizing study revealed that we are taller and weigh more than we did in the past. One standard would quickly become outdated.
  • Sizing studies are very expensive and labor intensive. Studies are not done frequently, so manufacturers will always be behind what is happening in the real world.

Loosely conforming to a standard while yet adapting to meet a customer's need.

Even if one standard to rule them all is unrealistic, we still need a standard. ASTM and the latest Sizing USA study have provided us with a standard that any manufacturer can use (for a price, of course). These measurement and sizing specs can act as a guide, a place to start. As a manufacturer develops their customer profile, they can adapt these standards to meet the needs of their customer.

Over the years, it's important to compare your product against these standards. I've seen patterns and sizing drift from these standards naturally through errors. These errors are not intentional, they just happen and can easily pass from one style to the next. So a careful study and comparison can bring things back. This includes measuring fit models and comparing them against the standard and analyzing customer returns due to fit issues. 

In-house size standardization

Once a sizing standard is established for a brand, it is important to adhere to that standard during product development. As an example, all new pants styles have the same finished length and waist sizes as specified. Variations in fit can come from multiple sources due to fabric variations (or problems), construction issues (taking too big/small a seam allowance, cutting errors), or variations in a pattern. You have to be careful not to draft a pattern from scratch every time. Pattern makers in the industry will use the patterns from an already proven style to develop the new style. This practice ensures consistent fit across styles. A quality control process through each step of development and production is necessary to find problems before they become big ones.

A few words on vanity sizing

Vanity sizing implies that a manufacturer wilfully chooses to ignore a size standard and relabel a size smaller than it actually is. I do not believe there is a vast conspiracy to do this intentionally. Instead I think manufacturers are trying to meet the needs of their customers while trying to conform to a standard.

*This blog entry was inspired from my reading in the book Sizing in Clothing and more specifically the article Sizing Standardization by K. L. LaBat. I made very few notes on this article and don't remember much of what I read. I did make a note that LaBat tried to prove the existence of vanity sizing by studying children's age-based sizing. I thought the argument was rather weak.