Showing posts with label Grading. Show all posts
Showing posts with label Grading. Show all posts

January 03, 2008

Grading Pants Notes pt. 1

The following are my notes on grading infant-toddler pants. Having a copy of the Jack Handford grading manual will be helpful in understanding what these notes mean. Hopefully you have at least read the introduction and the instructions for grading a bodice. If you don't have a copy of the book, save these notes anyway - they may come in handy.

These are the first of my notes on grading pants using the Jack Handford book. Part one of these notes is an explanation about directions and movements of the pattern pieces. Later I will talk specifically about grading pants, shorts, and what I think is a mistake in the children's chapter. Handford's book is a textbook and like most design text books he starts with grading women's styles. The book progresses from woman's bodices, pants, and skirts, to men's styles, and finally to children. When design/pattern making/grading book authors finally get to the children's info, the information becomes abbreviated and incomplete (if they include it at all). Handford's book is different because he does include infant and toddler information and it is more complete than any other grading manual out there. Still, he falls into the same trap. He assumes the student has worked through all of the previous chapters before arriving at the children's chapter. He assumes you have a strong grading background and understand his method completely. But what about those who have no interest in grading woman's clothing and skip ahead to the chapters with the most relevant information? This is what I did.

Now I do have a strong grading background - computer grading. Hand and computer grading are similar and Handford's method is how it is done in the industry. The direction of the grading is done in a similar fashion. The grade rules are similar. The grade steps are the same. But physically moving a hard, paper pattern around versus selecting points and entering relative coordinates is different. Despite that, I have a general sense of how a pattern should grow or shrink between sizes - and that helped me finally understand Handford's method better.

Directional movement in grading in and outTo start out, you will need to compare the grade instructions for women's pants to children. If you turn to page 79 (grading of women's back pant), you will notice arrows with words around each pattern piece. The arrows look like this drawing. If you flip over to the toddler pant grade (page 225), you will see arrows, but no words. It is at this point that Handford assumes you will know what direction is In, Out, Up, or Down. Now study the drawings of the women's pant and the children's pant. Do you see any other differences? There is one major difference that threw me off - I'll explain later...

Directions in pattern grading, in, out, up, downThe next thing to understand are directions. All patterns will move IN, OUT, UP, or DOWN. Handford shows how this works on page 6 in relation to a bodice. The children's chapter doesn't have these extra helps. So I drew arrows like on the right and below to help remind me of grading direction. I added the words to body center or to body side to remind me of how to move the pattern IN or OUT. As you can see, IN or OUT can change depending on whether you are grading a left or right piece (applies to front or back too). Directions may change again when grading darts. Be sure to study styles with darts to see the changes. Infant-Toddler styles do not have darts, so movements will occur like these drawings. Movements UP move toward the body head and DOWN toward the feet. UP and DOWN movements are always the same.

I hope I haven't thoroughly confused anyone yet. I felt like this brief explanation of the notation and movements was necessary before getting into more detail.

If you have questions, please leave them in comments.

October 04, 2007

Tag Board for pattern making


I have needed to order tag board (manila folder paper for patterns) for a while. Up till now I haven't needed very much. My patterns are small and a large, heavy roll of the stuff seemed excessive. I think I have found a reasonable alternative until I need larger quantities.

I did a search for tag board among the big box office supply houses. Sure enough I found one that sold it in large pieces (24 x 36) in a box of 100 sheets. The pieces are big enough that I can cut out quite a few pieces at one time and still have left overs. I further economize by not cutting out square or rectangular pieces. Technically, every pattern piece should be cut out of tag board and if I were to send them to a contractor, I would. Square/Rectangular pieces are cut using cutting guides & charts. I have a cutting guide for sleeve cuffs and skirts indicating the dimensions for each size, for example.

August 31, 2007

Too Many Sizes pt. 2

In my previous blog entry on this subject I discussed combining sizes to reduce the overall number of sizes produced. As I have been developing patterns for my new line of dresses, Prairie Roses, I have attempted to practice what I preach.

I have been doing all of the pattern making and grading for my new dress line entirely by hand. I do use CAD, but only for my employer who actually owns the system. I try to keep everything separate so there are no ethical questions (My patterns have different shaping and grading anyway). Also, I want to experience what most new designers experience since so few DE's can afford a CAD system. It takes soooo much time to do it all by hand, especially the grading. I am getting faster on the grading, but it is very time consuming. I have been using Jack Handford's book on grading and my graded patterns have turned out really well. The grade rules are beautiful - there is no other way to describe it. They are nice and consistent and all of the pattern measurements fall into an acceptable range.

My patterns fall into the infant-toddler size range and I have chosen to combine the 24M and 2T. I also added a 9 mo size, which is considered a half size and not usually included. I decided to let customers tell me whether they want a 9 mo or not with sales. It isn't that big of a deal to split the grade between the 6 mo and 12 mo. If it doesn't sell, it is easy enough to drop it. Anyway, my sizes break down like this.

3 - 6 - 9 - 12 - 18
24M/2T - 3T - 4T

You will notice I combined the 24M with the toddler group. This means my 24M/2T patterns will be based on grading from the 3T. I decided a 24M child has shaping more closely related to toddlers than infants.

In my infant grouping, the sample/base size turns into the 9M. Since the 9M is something I may not keep around, it doesn't make sense to sample in that size. I prefer to use a 12M as a sample size. If you move the 24M back up to the infant grouping and drop the 9M, then the 12M is the right sample size. Also, it is easier to find a more willing 12M child model than younger.

Now here is a dirty little secret in the childrenswear industry. Many childrenswear companies actually sample in the smallest size, 3M. This is because they end up making A LOT of samples and the samples are made from actual production fabric, not muslin. Sampling in the smallest size saves fabric. The dress form I made is actually a 3M, so that is my sample size too. It causes problems with drafting first patterns and grading. As soon as I can afford it, I will be buying a 12M form and sampling in that size.

July 25, 2007

When do you grade sewing patterns?

Amanda left a comment/question on a previous blog about grading. I thought the answer deserved its own blog entry.
I have what is probably a stupid question. Do you do the grading before or after you add the Seam Allowance to the sloper? Part of my brain says before because you are likely to get a better line, the other says after as it would be easier. I am loving your blog, thank you so very much.
Amanda, not a stupid question at all. The only stupid question is the one not asked. There is a lot of confusion about grading and the difference between a sloper and a block. Let's throw some definitions out and then I'll answer your question.

Sloper - a basic fitting pattern used by costumers and home sewing enthusiasts. The pattern does not have seam allowances, which are added later. People who use slopers do all of their pattern making without seam allowances.

Block - A pattern used by fashion designers and pattern makers which forms the basis of future styles. A block is a perfected pattern that has seam allowances. During the pattern making process the seam allowances remain on the pattern.

Many people believe that using blocks (vs. slopers) is an advanced pattern making technique. It's not really. The pattern making process is no different when using blocks, except for not having to add seam allowances. If anything, it saves time in production settings. It is important for the pattern maker to know what the seam allowances are - which are usually drawn onto the pattern anyway. The exception might be CAD patterns which may or may not have the seam allowances drawn. My CAD patterns do not show seam allowances even though they are there. I do all of my pattern making with the seam allowances already on the pattern. Occasionally, I will turn the seam allowances off to check measurements or to match up seam lines of complex pieces. CAD has greatly simplified the manipulation of seam allowances.

Now to answer the question.... Grading should only occur after the pattern has been perfected and the seam allowances have been added. If you add seam allowances after grading you just add more work to your project and you could introduce errors. This is especially true in a factory setting.

Now in theatrical settings, I know this would never occur. A cutter (aka pattern maker) does their pattern making in the size they need and then adds seam allowances during cutting. If they need two sizes of the same style, they will grade the "slopers". Finally, they trace the pattern onto fabric and add the seam allowances while cutting. This system works in the theater but is not precise enough for apparel production.

June 13, 2007

Resizing Vintage Patterns versus Grading

Sewing pattern and notions

The same reader from the previous post also asked:
Also, I found some info on resizing vintage patterns http://www.sensibility.com/pattern/resizepattern.htm thought it might be of interest.
I checked out the link and I do like the website. However, Jenny's pattern resizing tutorial is mis-named. She actually is describing a grading process. It is not a very precise method, but perhaps it would work for a custom or one-time project. I would still encourage my readers to learn a better method, especially for preparing patterns for production.

The idea of re-sizing patterns implies there is an inherent sizing problem which should be solved. If you buy a commercial pattern and you need a longer waist, then you would resize the pattern by slashing and spreading it longer to the required measurement. Jenny does describe such a process at the end of her tutorial.

Jenny goes one step further and shows how to alter an adult pattern into a children's pattern. The method probably will work, but it will require too much fiddling. Why not take a basic block the size you need and draft the same style?

I don't think I am being too hard on Jenny. She does have a nice website. Just realize her perspective is geared more to costumers and others who don't want to be bothered with details.

May 17, 2007

A Word on Handford and Children's Sizes


I have previously blogged about Jack Handford's book Professional Pattern Grading (I like this grading book!). I just graded my basic infant bodices using Handford's grading charts and I just wanted to pass on a few insights.

If you read my blog on children's sizing (Too Many Sizes!), then you will know that there is a lot of variety in how manufacturer's lay out their size ranges. Handford is not really any different. His sizing breaks down like this:

3M, 6M, 12M, 18M, 24M, 36M

You will notice that the 9M size is missing. A 9M is considered a half size between 6M and 12M. Some manufacturers include it and others skip it. After studying dozens of measurement charts, I tend to favor skipping it. Children grow really fast in the first few months of life, so there is no need to include lots of possible sizes.

Another thing to consider is his 24m and 36M sizes. His toddler sizes break down like this:

1, 2, 3, 4

Except for boutique/specialty shop stores, you don't really see toddler sizes denoted like this. Normally, the toddler range is 2T, 3T, and 4T (some throw in a 5T). Anyway, there may be some overlap between the infant and toddler sizes with your patterns. This doesn't mean you can grade all of the infant and toddler sizes together. You will still need an infant block and a toddler block. You may have some shaping differences between the two.

It took me some time to wrap my brain around his grading instructions. I could look at the diagrams and see that this was the type of grading done in the industry. Even computer grading takes it's cues from this method. The actual grading process, however, varies from computerized grading.

I am accustomed to working with all of the pieces nested together. I can select a grading point and enter in the X,Y changes. It really is pretty simple. Handford has you grade one size at a time. After grading one size, you cut it out and use it to grade the next size. Precision is absolutely key because mistakes gradually increase with each size. I eventually got the hang of it and found it to be pretty easy. Once I had all of the sizes, I nested them on top of each other and I could see how well it worked. And it did work well.

So now I have two sets of infant bodice patterns using the Handford method and an adaptation of Aldrich's measurement charts. I am going to compare the two to see which I like better. So far, there doesn't seem to be too much disagreement between them. I am also trying to decide if I should add in a 9M. Right now, I am leaning toward Handford.

April 18, 2007

I like Jack Handford's book Professional Pattern Grading!


You know you might be a little strange when you do a happy dance after receiving a new book in the mail on pattern grading. That was certainly me yesterday when I received Professional Pattern Grading by Jack Hanford in the mail. This book has long been on my Amazon wishlist and I finally bought it for myself.

This is the BEST book on pattern grading. If you own the Price/Zamkoff book, just stuff it in a corner and get this one instead. The explanations are very clear and complete. And yes, this is how it is done in the industry. It was so gratifying to see that what I have learned on the job, some of it on my own, IS how it is done. The other book is too complex and ignores men's and children's styles completely. Jack Handford covers all three categories very well. And it is so nice to see that children have not been ignored. He covers infant, toddlers, boys, girls, and juniors.

This book describes manual grading with a paper and pencil. Still the concepts can be applied to computerized grading. Most of my grading is done on the computer and I will be using this book as a reference.

In fact, this book is so good, that I will not be doing my last installment on my grading series (a pictoral demo). Handford demonstrates the process well enough, there is no reason for me to duplicate it. Can I say buy the book? I will probably blog more about grading in the future, so no worries there.

I will be going back over my infant pattern/body measurement charts to see how they compare with Handford's grading. I probably will be making some adjustments. I am not too far along on developing my own infant/toddler patterns, so this is a great time to go back over them.

January 26, 2007

Grading Stack Points

Grading stack point
I am going to try and get back to my grading explanations today. My head is a bit fuzzy after a long week and an especially late night. To review, just click on the grading category link to the right. Click on the picture for a bigger view.

The diagram on the left shows three possible grading examples. This is a basic front bodice pattern piece that is folded in half. Each example is called a nest meaning each size is stacked on top of each other from smallest to largest. The stars represent the point of origin for each grade. The numbers at each point correspond to a grade rule. I will briefly explain each of these items below.

By laying your graded patterns on top of each other in a nest, you can easily see if your pattern is grading proportionally. The stars not only show the point of origin, but the stack point. You can stack your patterns in three general areas and have the grade look different each time. In computerized grading, you can move your stack point anywhere you choose and the grading software will update your grades automatically. For consistency's sake, it is important to determine before you start grading where your stack point/grading point of origin will be.

Each stack point will cause your grading to look different. Most of the grading world uses Example 1. The point of origin is placed in the center of the pattern pieces and growth occurs in all directions. In Example 2, the stack point is placed at the center front waistline and growth occurs to the side and upwards to the neck. Example 3 is the same result as 2, but placed at the center front neck.

I prefer Example 3 and all of my patterns are generally graded this way. It makes the most sense to me and the grade rules are simpler. Most of the proportional changes between sizes occur this way in nature. A person's neck doesn't actually move upward in each size, but rather their waist moves down. Perhaps this is just how my mind works. In any event, you can choose which ever point makes the most sense to you.

I have been using the term grade rules rather loosely in my previous grading articles. Grade rules refer to measurement charts broken down into grade steps. Grade rules can also refer to the actual change that occurs at a point. In the drawings above, I have numbers assigned to each point. Those numbers can refer to a grade rule. For example:

Rule X,Y changes
  1. 0, 0
  2. 1/8, 1/8


You can create a chart like the one above, if you prefer. This method is used in computerized grading and each grade rule is placed in a grade library (specific to a size range). Once a style is ready to grade, you simply apply a rule to each point and the pattern pieces will stay graded regardless of pattern changes. It is less helpful when hand grading and may make things more complicated. To be honest, I rarely use grade libraries when computer grading. They can speed things up if you have consistently similar styles. However, things always need tweaking, so I prefer to manually manipulate the grade at each point. Most grading software will allow you to assign a grade rule from a library and still manually edit the point. The computer will begin a grade command by starting with rule #1 and working around through each point. Rule 1 is almost always set as (0,0) and it should always be your stack point.

When hand grading, you should start your grading at your stack point. Once that is set, you then move to the next point, say the neck-shoulder point and mark all of the changes there. Work counter-clockwise (or vice versa, if you choose), around to each point. Setting up a consistent method will help you keep things straight.

Ok. Enough explanation. Decide on your stack point and get ready to grade.

January 08, 2007

Points of Measure and Grading

In a previous grading blog, I showed the first step in developing grade rules. I usually break my measurement and grading charts into two charts. Here is an example:

An example of developing a grade rule

I usually stop at the middle chart and work the rest of the math out in my head as I grade. Some of you may want to break your measurements down even further. If a pattern piece is symmetrical, you can grade half of the pattern at a time. The third chart shows the grades for half of the pattern width.

My charts have a column on the left titled POM, or point of measure. Those points of measure should correspond to a drawing like this:

Points of measure on a pattern piece

The measurements in the top chart above are based off pattern measurements (which are made up for this example), rather than body measurement charts. The grades are developed from body measurements. To grade successfully, you will need to take a lot of measurements off your base size patterns. For a bodice pattern, you will need armhole circumference, across the shoulder neck circumference, neck width, neck depth, and possibly more. Work between your body measurements, pattern measurements, grade, and ease requirements to develop appropriate grade rules for each point of measure. BTW, if your pattern measurements are finished measurements (minus seam allowances), you can use these charts to measure finished garments while doing quality assessments.

There are standard reference grading charts available from various sources. You can refer to them to develop your grade rules, if you like, and it may save you some time. Standard grading charts are usually available for adult, most often, women's clothing. Children's grading charts are available, but I have found them less useful. There are too many variations in children's body measurements, and every company has their own set. I usually have to develop grading charts that are unique for each company. When a designer asks me to grade a pattern, I have to work off of their measurement charts and basic pattern pieces for the grade to make sense. I will compare their measurement charts with my own to make sure their measurement and grades fall within an acceptable range.

If you do use a standard reference grading chart, you will need to double check your pattern/body measurements across the range. Standard grade charts do not accommodate variations in body type that your company may try to fit.

In the next grading blog, I will begin to explain the actual process of grading.

December 28, 2006

Grading Rulers

Kathleen Fasanella posted a blog back in Feb 2006 about grading rulers. Imagine my surprise when I opened a book I picked up at a thrift store. Inside the front cover was a little used hinged grading ruler in it's original packaging with instructions! The ruler was stashed in an older edition of the Price/Zamkoff grading book. The book was priced at a measly $2 - the original price sticker for the ruler was still on the packaging of $5.35. Funny thing is, I bought the book about 3 years ago and stuck it on a shelf. I only opened it up a few days ago as I was working on my new infant grading charts. I wanted the book as a grading reference, but rarely use it because of how poorly it explains grading. What a great bonus to find the ruler!

A hinged grading ruler About 98% of the grading I do is in a CAD program. Grading on the computer is so easy! Select a point and tell the computer how much growth should occur in the X,Y directions. It redraws the curves automatically. It is easy to double check the grade in the larger sizes by laying the pieces on top of each other or walking the pieces along side.

Every CAD program varies in ease of use. I have done computerized grading using Gerber's Accumark, Autocad/Betacad and Optitex. I will blog in the future about the differences between the three. Suffice it to say, Optitex is the easiest to use thus far, and quickly becoming my favorite. Grading by hand, is another story. It is tedious and takes a lot of time. I can see why grading is considered an art form. I am grading my personal patterns by hand and it is a big learning process.

In design school, I learned to grade with only a ruler. My 18" clear ruler with 1/16" increments, is photographed above. Grading with only a simple ruler is fairly straightforward. You measure out the changes and re-draw your pattern for each size step. Using a grading ruler makes the process so much simpler! I graded my infant flat block patterns with the grading ruler in a couple of hours (I was re-working some of my grades at the same time). The ruler is marked in 1/16" increments. Your grade rules need to be in 1/16", 1/8", 1/4", 1/2" increments to use this ruler effectively, which means you may need to re-work some of your basic pattern measurements to make grading easier.

I hope to demonstrate the process of actual grading, but for now I am enjoy playing with my lucky find!

Comparing Butterick 6030 neckline measurement

An example of a well fitting boys shirt

I didn't realize I had so many boys' shirts in my stash! Each shirt has a slightly different construction technique. They range from casual to dressy. Some have a convertible collar with a facing and others have a traditional 2-piece collar. This is a great resource for me to figure out more of what is wrong with the Butterick pattern.

The first thing I did was take some key measurements off of the size 24M shirts. The button bands averaged 1.125" and I adjusted my new pattern accordingly. The second measurement was the necklines. Both 24M and 2T shirts measured 12 inches, which I think is right on target. Compare these numbers:

Actual neck measurement = 10.125"
Butterick neck measurement = 15" (4.875" of ease!)
My pattern measurement (1st attempt) = 14" (3.875" of ease)
Both RTW shirts neck = 12" (2" of ease, right on!)

To draft the neckline of the pattern small enough, I need to have a basic 24M block made up. I am not going to keep guessing -- it just wastes too much time. This is enough motivation for me to work on my basic blocks again (My New Year's Resolution!). I pulled them out yesterday and made some important decisions. I can officially announce I have a basic bodice block that I like. The next step is to figure out my grade rules and grade my basic block up to a 24M.

Figuring grade rules and grading my blocks will take me some time, so the shirt project will be put off for a little while. In the mean time, I may get back to my promised grading blogs. Hopefully, you won't get too bored by it. Grading is as dry and boring as a topic can get.

November 15, 2006

Creating a grading standard pt. 3

2019 notes - The original images for this blog entry have disappeared and I haven't had time to recreate them. I do have more complete examples in my ebook, The Organized Fashion Designer.  
 
I finally made my example measurement/grading charts. It took a little dancing as I had to create them in a spreadsheet, export them as a PDF and then convert them over to a jpg. Before I get too far, it may be helpful to review my previous blogs on grading: Creating a grading standard and Creating a grading standard part 2. You should have your own measurement charts handy. BTW, the measurements in my charts are real. I found them from the Sears website. I do not necessarily endorse Sears measurements as the industry standard - they were just handy (To be fair, their measurements are pretty good). Your own measurement charts should be far more complete and detailed than these for pattern development and actual grading anyway. This is the first step I take in developing actual grade rules.

Right off, I hope you notice a few important things. First, I have clearly marked my sample sizes. In this example they are sizes 10 and 10+. Each chart is labeled clearly. You would think these things should be obvious, but you would be surprised at what I have seen. Hanging off of the left side are numbers. These numbers are points of measure and should correspond to a How to Measure diagram (a future blog) and are not relevant for the immediate discussion. Also notice that my size ranges differ. The regular sizes run 7-16 and the plus sizes run 8+ to 18+. This is a fairly typical difference between the two groups. Also notice the difference in the measurements. There should be some obvious differences between a Misses and a Plus sizes chart too.

Usually, I have my grading chart separate from my measurement chart. I combined them here so you could more easily see how I am developing my grading rules. In the column for my sample sizes, I have placed a zero. A sample size is also called a base size in grading. It is your starting point and each subsequent size will grow or shrink proportionally off your base size. Next I subtract the difference between the base size and the next largest size. In the regular size chart, you will notice there is a 1.5" difference in the chest measurement from a size 10 to a size 12. This difference is called a grade step. Next I subtract the difference between a size 14 and a size 12. I don't subtract Size 14 from a size 10 because that is not the next grade step. Continue to subtract the next larger size with the previous size.

To calculate the grade for your smaller sizes, subtract your sample size from the next smaller size. Be sure to add the negative sign, which indicates the grade is getting smaller. Repeat by subtracting each size with the next smaller size. Create a grade for each measurement on your chart.

You will notice that the measurements and grades all have beautiful numbers. The measurements increase or decrease proportionally causing the grades between sizes to be relatively the same. This is where the art of grading and measurements come into play. I can guarantee that actual body measurements are not this pretty or consistent. These numbers have been averaged and rounded and are based on a large body measurement sampling. The numbers have been intentionally made easy to work with. Your measurements should be easy to work with too and you can adjust them as necessary.

What about accuracy? Rounding does introduce inaccuracies in your measurement charts, but only a little. If you look at growth charts, you will find that certain measurements will fit 50%, 80%, 95% or 97% of girls. If you adjust your numbers up or down, you will want to make sure those numbers fall into the 95% percentile. Adult measurements and sizing are similarly developed. Because these measurements are based off of measurement studies, it means a real girl will pick the size that most closely matches her measurements. Your measurement numbers just need to fall within the highest percentage category. You can round to the nearest 0.5" or 0.125", or whatever. Adjust your measurements so that you get a relatively consistent and even grade across the sizes. In my regular sizes I have a consistent 1.5" chest grade and a 2" grade for my plus sizes. Sure, you could throw in what ever grade steps you choose as long as you have justification for it.

Finally, I hope you can see the difference between the regular and plus sizes. Not only are plus size measurements larger, they are proportionally larger (the grade step is larger). This is why you absolutely cannot grade a plus size pattern from a regular sized pattern piece. Keep both categories, pattern pieces, measurements and grades separate from each other. I promise it will save your sanity.

I know this is a lot of explanation for this first step. If anyone has a question about this, just leave them in comments and I will try to answer them. In my next article in this series, I will explain how to create grade rules based off your first grading chart.

October 27, 2006

Creating a grading standard pt. 2

In a previous blog, I wrote about the first steps in creating a grading standard, but failed to discuss the details. It would be helpful to also review my blog entry titled Too Many Sizes! In this blog, I will try to explain grading terms and the rules by which grading can occur. In the future, I will show how to develop your actual grade rules and how I grade a pattern (which is different from any other method I have seen).

There seems to be a lot of confusion about grading. Some people view grading as a magical process that can turn your beautiful pattern in one size into any other size you desire. Before anyone can grade your pattern, you should have already done some homework. You should have chosen a category, size range, and measurement chart. Your category and size standard should be fairly simple. You should only be working in one category and your size range should not have more than 6 sizes. You may want to work in men and womens plus and regular sizes all at once, but it is just not possible.

Now, I have to stop here for a moment and explain the concept of categories. I don't know if this is the appropriate term or not. I work in a children's category, but you may work in Misses, Juniors, Mens, or whatever. Within those broad categories, there are sub-categories or classifications based on your sizing system. A classification is based on a specific figure type such as Misses, Petites, Plus, or Talls. Each of these designations have a separate and distinct sizing system. You can't magically start with a Misses size and turn it into a Plus size by grading it. That is not how grading works, so don't even attempt it. There is no magic formula.

Grading is a simple, yet difficult concept for people to grasp. Grading is a process by which a base pattern is proportionally changed to create smaller or larger sizes. Grading is always based on a set of measurements specific to a size range and classification. Successful grading does not change the overall proportions of the intended design as the size changes. This is why a size range should be limited to about 6 sizes. Any more than that and the largest or smallest size will be proportionally wrong.

Successful grading is all about having a good starting point. A base pattern is a pattern created and perfected to fit a sample size. From that base pattern, you will create the other sizes in your size range. Now some of you want to offer Plus sizes in addition to your Misses Sizes. It should be as simple as grading your base Misses patterns up to the appropriate plus size, right? After all, it would save a great deal of work. You already have a perfect pattern and why would you want to go to the work of creating a whole new set of patterns.

The reality is, you will have to create a whole new set of patterns in a new base size contained in a new size range and classification. I know this sounds like a lot of work. The truth is that it is, at least initially. You will have to develop a set of base patterns for your Misses sizes and a separate set for your Plus sizes. You may sample a new style in a Misses size initially. Once a style is approved, your patternmaker will then create patterns in any other size ranges you want to offer. The process required to create the plus size patterns will be very similar, if not identical, to the process required to draft the Misses size patterns. There may be a little tweaking for fit during sampling, but the process will be faster than the original style development. Your patternmaker will already know what should be done.

For example, one company I work for will create a new style in a size 5 (in a children's size range of 4-6x). They then decide they want to offer that style in the entire range 2T-16 and plus sizes. I have already broken up the sizes into ranges of 2T-4T, 4-6x, 7-16, and 8+ to 20+. I then make patterns in the sample sizes of 3T, 5 (which is already done), 10, and 10+. The patterns for each sample size are then graded within their range. It may sound like a lot of work, especially if done entirely by hand. Since I work in a CAD environment, I can accomplish this task in less than a day. By hand, it may take 2-3 days.

Going back to our previous example......Once your set of Misses patterns and Plus size patterns are finished, you will then send those off to be graded. And this is where you have to create your grade rules. To create grade rules, you will need your measurement charts. So here is your homework assignment. Read your measurement chart. If you are offering more than one classification, compare the two. How does a Plus size differ from a Misses? Do your measurements make sense? Do the measurements decrease for the smaller sizes and increase for the bigger? In the next blog, I will show how to create your grade rules from your measurement charts. Once you see the grade rules, you will then understand why you can't grade a Misses size into a Plus size.

June 27, 2006

Creating a grading standard for children's clothing

Before I can move on to the grading question, I must make a couple of comments on my previous post. The best time to determine a sizing standard is at the very begining of your company. If you have been in business for 30 years, for example, it will be very difficult to change things around. So please, please do your homework.

Another thing, you can make your sizing standard anyway you want. Even though I am suggesting a simplified sizing standard, it may not be appropriate for you. If your intended customer is a big box retailer, it may be too simple. In fact, they may not like it. They are accustomed to choosing from a lot of different sizes. If you become part of a private label program, they will tell you what the sizing standard should be anyway. If you have something similar already set-up, there will be less stress for your patternmaker. Again, the sizing standard suggested in the previous post would be more appropriate for a company targeting specialty boutiques and small retailers.

Ok. Now the grading questiong...

"Can't we use the 3mo size for our base size and grade everything up from there?"

The motivation for this question is to save some work. In essence you make your pattern only one time and let the grading take care of all of the other sizes. While the idea is good, it presents some problems.

First, it is important to know how a child grows. A very good description and diagrams are shown in the book Patternmaking for Fashion Design by Armstrong. In my second edition of the book, it is on page 674. Up to about age 3 children are cylindrical in shape. There is little differentiation between chest, waist, and hips. At about age 4-5, girls start to develop a waist. At age 8, there is more definition and curves. Boys and girls are similar in shape up to about age 8.

Because there is a change in body shape at regular intervals, a patternmaker will break-up the sizes like this:

0-3M to 24M, 2T-4T, 4-6x, 7-16

By breaking up the patterns into these size ranges, a patternmaker would then make base size patterns in a 12M, 3T, 5, and an 8 (or whatever sizes are chosen). You could sample your initial style in any size you prefer - hopefully a middle size. When the design is approved and read to go into pre-production, the patternmaker will then make patterns for your style in each of the other base sizes. Those patterns are then graded for each range.

Some manufacturers will go to the trouble of sampling their style in each range. Retailers like to look at more than one size range because they have to "see" how to merchandise their floor areas. It is possible you will end up making a lot of sales rep's samples if you plan on selling the whole range. These extra samples are called sisters or brothers.

Even with our simplified sizing standard, you would still break up your sizes like this:

0-3M to 3, 4-6, and 7-16

Now some design entrepeneur's may still insist on having only one base size and grading everything off of that. What will happen is you will introduce errors into your patterns in the extreme ends of the range. The grading will be more complicated. The fit will be off in the transitional sizes between infant to toddler, young child to older child. For organization sake, your patternmaker/grader will greatly appreciate having things broken down into simpler groups.

Also, you will be bucking industry standards and not playing by the rules. Walk into any department store and look at how the children's clothes are arranged. You will notice that the clothes are arranged together in the size ranges we talked about above - infant, toddler, young child (4-6x), and older child (7-16). Your order form should have your styles broken down similarly.

By this point you are probably thinking that it is still a lot of work to make that many patterns for each base size. If you have a CAD system with nifty pattern drafting and grading capabilities, it isn't really that big of a deal. Even if you had to do it by hand, it should only take a day or so. Your patternmaker will be just repeating the same drafting process over and over again. If you make dozens of styles every season, you may seriously consider investing in a CAD system.

June 26, 2006

Too many sizes!

I am currently in the process of rewriting this article for another project. A lot of what I wrote in 2006 is a reflection of my thinking back then. I have since refined my thoughts which will be published later. So please consider this article a bit out-of-date.

One designer asked me two fundamental questions. At the time I wasn't sure how to answer them. The first is really a grading question and the second a sizing standard. Both are related. To keep things simple, I will start with the sizing standard question.

"Why are there so many sizes for children's clothing?"

Because children grow. Ok. That is the easy way out. The truth is that children grow and manufacturers try to have a range of sizes to choose from.

The other half of the question was, "Can we have fewer sizes?"

This is a much more complicated answer. Because children's clothing can cover such a wide range, it is possible to have a lot of sizes. One company I worked for produced clothing from Preemie to a size 16 - not including the plus sizes. When you break this down it looks like this:

Preemie, NB, 3M, 6M, 9M, 12M, 18M, 24M, 2T, 3T, 4T, 4, 5, 6, 6x, 7, 8, 10, 12, 14, 16.

This is a whopping 21 sizes! This complicates bookkeeping and sales information incredibly. If you create a style in one colorway, then each size will have its own SKU (stock keeping unit). If you add a colorway, then each size in this style can have two SKU's - one for each color. The company wanted to try and reduce the number of SKU's each season. This particular company produced a new line every 4 months which consisted of dozens of new styles. Thinking about it can give anyone a headache.

To reduce the number of sizes, you have to either combine some of the sizes into ranges and eliminate some duplication. The duplication is the easiest to see first. There is very little difference between a 24M and a 2T. A 24 month old child is essentially a 2 year old. The T simply means that ease is added to the pant area for a diaper.* Most 24 month old children and 2T children are still wearing diapers, so there should little to no difference in the patterns there.

*I'm not sure where the idea that the T in the size 2T implied the size included diaper ease. I repeated this idea because it was all I knew at the time. After a lot of research, I now believe this idea is a myth that has been perpetuated around the internet. I have found no size study information that supports this idea. Rather it has become a standard custom to refer to toddler sizing in this way. As a pattern maker I always included ease for a diaper in the toddler sizes because they wear diapers! The ease is not much more than what is needed for wearing pants anyway. Diapers do not add much bulk these days. Perhaps in years gone past in the age of cloth diapering, it was more of a concern.

The other likely duplication is the 4T and 4. Again these sizes overlap with only a slight difference in the pant area for a diaper. Most four year olds are potty-trained, although it is possible that some are not. In any event, if you manufacturer girl's dresses, this is another area where sizes could be combined. Some companies have started putting out a 5T, but it would be unusual to find a five year old wearing a diaper.

The next size duplication looks like the 6 and 6x. In this case, there is a fitting difference introduced. There should be little girth difference in the patterns, but there will be a length difference. A 6x is a taller size for a 6 year old. Some retailers combine the 6x with a 7. This is where it would be important to know your customers before eliminating or combining sizes.*

 *(Please note that this paragraph has been modified. I made a big assumption that was just wrong stating that the size 6x is a plus size version of the size 6. This isn't true. It is a taller version of the size 6. In any event, the paragraph above has been edited with the correct information).

So now our sizing looks like this:

Preemie, NB, 3M, 6M, 9M, 12M, 18M, 24M/2T, 3T, 4T/4, 5, 6, 7, 8, 10, 12, 14, 16.

And this is where I have to interject. Retailers, and especially big box retailers, do differentiate the sizing of the patterns on the sizes we just combined. A 2T is just a little bit bigger than a 24M, even though it really shouldn't be. Consumers have become accustomed to this type of sizing system and so have the technical designers in the business. In other words, don't expect any big changes anytime soon. This proposal is a way to simplify things. You are more likely to find a simplified sizing standard in boutique or specialty stores.

Ok, back on track now. The next step is to create a range of sizes. This is simplest in the infant sizes and another grey area. Every major manufacturer has come up with their own size range break-down, and it really is all over the place.
I really like how JcPenney has broken down their infant size range:

Newborn, 0-3M, 6-9M, 12M, 18M, 24M/2T

The nice thing about this sizing standard is that there are no overlapping of sizes.
Some companies will create a range like this:

Newborn, 0-3M, 3-6M, 6-9M, 9-12M, 12-18M, 18-24M

As you can see, there is a lot of overlapping. This could cause confusion for a customer because it is difficult to pick just the right size range. Also, this doesn't reduce the number of sizes carried.

If we eliminate the newborn and preemie sizes and use the size range from JcPenney, we would get this:

0-3M, 6-9M, 12M, 18M, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16.

If you look carefully, you will see that I eliminated the 24M size and the T's on the 2, 3, and 4. This is where you have to decide how the size will appear on the care/content tag or hang tag. It would be best not to confuse customers - keep things simple and logical here.

You will also notice that there seems to be a size missing in the infant sizes. The size 6-9M is often combined because either the 6M or the 9M is considered a half size between the 3M and the 12M. This is obvious when you study measurement charts, so just take my word on it for now.

The other thing to consider when generating a size standard is the patternmaker/grader. The size 0-3M, for example can be created in one of two ways. The measurements of the Newborn and 3M could be averaged out or the patternmaker could just make the patterns a true 3M. In order to fit the most children, it is best to make the patterns fit the high-end of the range. In our example, the patterns would be made in a 3M. The clothing will fit loose on the small end of the range, but kids grow fast. The only exception might be sleepwear which needs to fit snug to the body in all of the size ranges. This is another place where you need to know your product and customer well.

By following this example, we have gone from a whopping 21 sizes to 15! While this still creates a lot of sizes, it is so much simpler and easier to understand.

0-3M, 6-9M, 12M, 18M, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16.

The next question to address is the grading question. And that will have to wait for tomorrow.

April 27, 2006

Children's Sizing and Measurement Standards Vary by Company

After studying and comparing all of my size charts collected from various sources I have come to realize the search for a good standard may be in vain. Here is just a brief example of one meausurement and how it varies among pattern drafting manuals and retailers.

Size 8 child: Major US Retailer
Bicep (inches) : 7.75
Recommended Ease : 1.5-2.0
Draft Line : 9.25-9.75

Size 8 child: Armstrong
Bicep (inches): 8.125
Recommended Ease : 2.875
Draft Line: 11

Size 8 child: Mortimer-Dunn
Bicep (inches): 8.75
Recommended Ease: 1.5-2.0
Draft Line : 10.25-10.75

Size 8 child: Dressform Co.
Bicep (inches): 7.75
Recommended Ease : 1.5-2.0
Draft Line : 9.25-9.75

As you can see there is quite a range in measurements. To fit the most average child, it is best to fall in between the range. But it still begs the question of who is correct? The Armstrong measurement is especially suspect because she recommends far too much ease in her drafting measurement.

For my new blocks, I have decided to use the Aldrich charts. She has statistical data to backup her charts. The US retailer and dressform co. charts are based off of the 1977 study and have been adjusted/updated over the years. I don't know where Armstrong and Mortimer-Dunn got their measurements, but their numbers seem odd. As far as I can tell, Aldrich is fairly close to the Major US Retailer. I am currently in the process of converting her measurements over to inches, to the nearest 1/8". This introduces an error into her measurements, but I am most comfortable using those units. Once I fine tune and tweak the numbers so they look right and are easy to work with, I will then compare my charts to those above and make sure I fall somewhere in the range. And I am still toying with the idea of working in metric anyway. I am unsure how my US customers would respond...

The next step is to draft some basic blocks and sew-up a fit sample.

My sources:
Major US Retailer - Kept confidential. Their size charts were last updated in 1981.

Patternmaking for Fashion Design by Helen Joseph Armstrong (5th edition) - her third edition has an even larger measurement for a Size 8 bicep and still too much ease. I have no idea about the fourth and fifth editions.

Pattern Design for Children's Clothes by Gloria Mortimer-Dunn - the book shows basic pattern drafting skills but her size charts are a bit odd.

Dressform Co. - kept confidential, but they have one of the better charts I have seen for infants.

Metric Pattern Cutting for Children's Wear and Babywear (4th edition) - the best book by far. I have not cited her bicep measurement because I am still studying her charts.

April 19, 2006

Sizing Up Children pt. 2 : How to find size charts for children

"The problem is children’s clothing manufacturers cling to their 30+ year old size charts. They protect their sizing information like a trade secret (not uncommon in every segment of the fashion biz). And while major studies are being done on men and women, they are not being done on children. (If I am wrong, please let me know)."
After doing some more reading at fashion-incubator, I discovered I am only half right. The 30 year old study on children's measurements done in 1975/1977 is publically available here: Anthropometric Data of Children. This is the data that most manufacturers continue to use. Since it is freely available, there is not much incentive to change. I have been using size chart information based on this data for at least 10 years because this is what the companies I worked for used. To be fair, it is still fairly good information.

Another source for sizing information is available from ASTM International. Kathleen Fasanella at fashion-incubator.com lists the documents to search for at her blog: How to obtain sizing and grading info. This data set is updated about every five years or so. Even though the data information is priced fairly, you still need to buy 3 charts to cover all children infant through teenagers, a price of about $90. The other thing to consider when purchasing from ASTM is that you only license the information. Be sure to read the license agreement! You are given permission to download on one computer and print out only ONE copy of the charts. You also give permission to ASTM to come and inspect your company computer and materials at any reasonable time to ensure you are complying.

As a small company, I do not like this license agreement. What if I have two or three technical designers who need access to this chart? My costs for this information multiplies! Plus, who wants to allow some other company/organization to come in and inspect your premises at will?! I wonder if ASTM has ever tried to enforce their license?

I also don't like the propriatary nature of the data. The only way to get cooperation from businesses to standardize is to make the information available for free. I realize as an organization they need to make money to support a needed role. But they could take a hint from other opensource projects and raise money by donation or some other model.

Because of the difficulty with ASTM, I now understand why companies continue to use 30 year old data.

April 18, 2006

Sizing Up Children and shopping difficulties

In the March 2006 issue of Redbook magazine, Melissa Schweiger attempts to explain the difficulty of creating women’s fashion. The disparity in body shapes, weights, and sizing is an evolving and complex task. Fashion companies each create their ideal customer and manufacture clothing based on specific sizing. But all too often women fall in between sizing or have different proportions. Many women have to try on a mountain of clothes to find something that finally fits.

Schweiger makes some interesting points about the changing shape of American women. Many of these ideas also apply to children’s fashion and sizing. Below, I highlight some key points:

Arbitrary Sizing

Each manufacturer develops their own sizing system. In women’s fashion the sizing numbers are relatively standard. For example, the sizes run 2, 4, 6, 8, 10, 12, and so on. In infant clothing, the sizing varies from label to label. One place will size 0-3, 3-6. 6-9, 9-12, 12-18, 18-24. Another will size 0-9, 9-12, 18-24. Some simply place a label with corresponding weight such as 19-26lbs. Stores like the Gap hand out info cards to help the consumer determine the right size.

After determining one size for one label, you will be out of luck at the next store. A 6-month-old baby can easily wear any size labeled 6-18mo. The added difficulty of fitting a baby is that they get fussy. If you can’t stand trying on 10 pairs of pants, imagine an infant after one pair.

Changing Shapes

According to this article, American women have changed. They are a bit taller and heavier. American women are more ethnically diverse. The challenge for manufacturers and designers is to design a product that fits a more diverse range of people. Some are making attempts, some refuse.

The general consensus among children’s fashion professionals is that children are changing along with their parents. They are taller and heavier, and more ethnically diverse. Childhood obesity and inactivity play a part in changing shapes.

The problem is children’s clothing manufacturers cling to their 30+ year old size charts. They protect their sizing information like a trade secret (not uncommon in every segment of the fashion biz). And while major studies are being done on men and women, they are not being done on children. (If I am wrong, please let me know).

Shopping for children who fall outside of the norm has tremendous difficulty. Plus sizes for children are not stocked in many stores, despite the apparent increasing demand. And if there is truly a demand for children’s plus sizes, it is hard to gauge. Children in this category move to adult sizes much more quickly.

Overall, this magazine article was an interesting review of the difficulty faced by clothing manufacturers. Well worth the read if you have wondered why you can’t find anything that fits.
Additional ideas and fitting information can be found at http://www.fashion-incubator.com.