How to create grade rules 3

Posted by Kathleen Fasanella on Apr 3, 2008 at 3:20 pm / Fit and Sizing, Grading, Tutorial / Trackback

For the previous entries in this series, see here, here, here, here and here. Reminder: for purposes of explanation in the exercise of deriving grade rules, we’re using the CS151-50 (opensource). I’ve linked to it enough times in the previous entries so you should have it by now. And finally, we’re cribbing off the spreadsheet (in the forum) of needed grading changes from the CS151-50 to do the actual portion of this work.

Continuing from the girth rules done Tuesday, the lengths are easier. But first I want to show you something because now you have to keep track of grading notation. I don’t know how many have seen this. If you have my book, go to the grading section “how to map a pattern” pp 173 on. Otherwise, this will be familiar to old-school pattern makers. I don’t know how many people still do this today. I still do. Below is a pattern that is mapped with the measures derived in the girth exercise.

This manual pattern based system shows each point with crosses indicating the amount of grow at that point. The crosses indicate x/y coordinates. You’d shift the points the indicated amount using a grading ruler or grading machine. You can even use a 2×18 ruler for this.

Question: Those of you familiar with this system, how did you learn it? I learned it on the job but never found it in any books (a vast oversight in my opinion which is why I included it in mine). Later, I found similar guidance in the instructions that came with the Dario-grade-o-meter but I’ve since misplaced it. Anyone still have a copy of that lying around?


Anyway, there’s three -no four- basic ways to track and store your notation. I prefer to make notation right at the grow points on the pattern piece as I go along if I’m doing it manually. CAD systems do it differently. In OptiTex, you do it “on the fly”; it’s pretty cool how it works. Until I get good with the software, I plan to keep the grading notation on the hard copy for reference. Here’s a screenshot using the software. The grade (girth only) of point 2 (shoulder/neckline) is shown.

Another way to keep track of your grading points is in PLM/PDM software. I’m kicking the tires on StyleFile (won’t launch till 4/15) but I can’t figure out where to input that right now. The last way to do it is with a spreadsheet or a manual paper system.

Returning to the deriving the length rules from the CS151-50 sizing chart (cheatsheet in the forum) here’s a screen of the lengthwise size differences from which we’ll get the rules:

Right away, you’ll notice that the length differences are much more dramatic than the girth differences, especially when compared with adults. Kids are getting taller than they are wider. You may also notice that the rate of grow varies. As any parent can tell you, kids shoot up and then taper off. They’re still getting taller but not at the same rate as before.

Scye depth is first. This shows the armhole getting longer 1/4″ per size until size 6X which is kind of a half size of a still larger size (last size before the size break and you have to use a different pattern entirely for 7-14).

Shoulder and arm length. Nobody said grading was an exact science and I’m about to prove it. Remember Tuesday when I said that shoulder length was included in girth because it was a horizontal measure? Well, at that point we’d decided to use 1/8″ (half of the quarter of the total chest girth grade). Go back and look if you don’t remember. Today’s chart is showing a range of sizing differences of 1.5″ to 1″ (again, rate of grow tapers off in the larger sizes). Technically, you’d subtract what you’d added to the previous shoulder grade from this total measure, to figure out how much longer you’d make the sleeve in each size. I guess this is included in vertical (length) grades because the arm hangs down.

Cervicale to the waist. In adults, this is about two heads (2/8 of total height) long. This chart shows the CB waist lengthening by 1/2″ per size which is a pretty dramatic difference. In adults, it’s half that, about 1/4″ per size.

Waist height we can skip for now. In a previous entry, I’d described this measure as from the floor up to the waist so it won’t be useful for grading purposes for a bodice -what we’re still working on. It’s useful for pants though.

Waist to hip is useful and listed as 3/8″ per size. Still, this strikes me as too much. The reason is, the waist to hip equals a little bit less than another head, so you’d add half the CB grow (2 heads) measure to grow down from waist to hip (for tops). At least for adults. Following that rule of thumb -even for kids- it’d only be 1/4″.

Next time I’ll have to remember to add up all of those lengthwise grows and see how they match up to the reported total height increases for each size. I also have to create another pattern showing all the final notation because the piece I’m using as an example, doesn’t go past the waist.

I bet by now you really understand why folks tend to keep a lid on their grading, huh. I don’t expect you to believe this but it’s a lot easier than it sounds. And, I’d agree with the suggestion that a video would be helpful. It also wouldn’t hurt to get a grading book. This series is only intended to explain how one derives grade rules from sizing charts.

9 Responses to “How to create grade rules 3”

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Rachel
April 3rd, 2008
8:01 PM

Hi! I just wanted to say that I didn’t mean anything negative by suggesting a video. I do understand that the series isn’t about teaching grading. I’ve been a bit frustrated on my own search to find good instruction on old school hand grading. I do have Kathleen’s book and it is definitely very descriptive and I also have Professional Pattern Grading for Men, Women and Children by Handford, but even with these tools, I feel as though there are some key tools of wisdom that only a professional would know–things that are so in-grained that it’s simply second nature.

Thank you again for the insight on this series. I really enjoy your blog. -Rachel

esther
April 3rd, 2008
9:16 PM

I have never made grade notations, even when manually grading. I have used CAD for most of my career so I just refer to my cheater grade sheets or look at the notation on the screen. This and previous blogs have helped me improve my grading technique but it is doubtful I will ever place grade notations on my paper patterns. I have never needed to and it is not a habit. My training instructors never demonstrated it either…

J C Sprowls
April 3rd, 2008
9:40 PM

@Esther: Neither did my instructors. But, I’ll tell ya, I re-read the section in The Entrepreneur’s Guide on grading and the light bulb went on. And, it was this tiny little notation that gave me that ‘a-ha!’ moment.

I’ll admit, I’ve lazy about keeping up with it. But, I think I’m going to force myself to incorporate the notation as a standard. I feel the anthropological evidence is worth the extra minute because it allows others working behind me to know where I’ve been.

[Corporate speak: “business continuity” – ya never know when an Employee is going to win the lottery!]

heidi
April 4th, 2008
12:04 AM

Hi Kathleen
This is the only grading book of value I know
http://www.abst-institut.de/englische_ausgabe.html
but it covers only woman wear.
LG

Heidi

Penny
April 4th, 2008
12:40 AM

Kathleen, Yes I have the grade instructions that came with my Dario Grade O Meter, 22 years ago! I’ll send them to you if I can find them buried in a box somewhere below the house. I was first introduced to the fundamentals of grading in a 2 year apparel design program at the Seattle Central Community College.

I’m totally old school, still use the Grade O Meter and I do use grade notations. It’s the first thing I do before grading a pattern. After I’ve determined how a style will grow, I go thru and briefly notate the key grade points. Some styles can be difficult to figure out where and how they will grow, so the notation helps to keep it all straight in my brain, so I only have to think it thru once. Sure there are standard grade amounts to follow, but these don’t always maintain the integrity of the styles proportions in conjunction with fit. For instance in dealing with plus sizes where you often have a 3″ grade, it gets tricky especially in the shoulder and armhole areas. And then continuing on past the 3X size, the grade changes again and depending on the style the grade can be different for every size going up. In other words, nothing is written in stone with grading and once you “get it”, it really becomes a matter of fit and personal preference.

dosfashionistas
April 6th, 2008
2:18 PM

I never wrote the grade on the hard pattern when I graded by hand, but I used to make a rough sketch of the pattern piece for each size I was grading and note the total grade for each grade point on that. I get easily confused with math, so I needed to have it in front of me rather than having to remember that I was going up three sizes so that would be 3 times whatever the grade was. I could have the sketch right by my side and see that for this size it was this much x and that much y at that point. Just another system, and I don’t remember where I learned it. Certainly not in school.

And “Amen” to Penny on plus size grading. Wish I could get together with her over a cup of coffee. Shoulders and armholes are something I definitely have my own ideas on…

Sarah@dosfashionistas

deirdre
April 14th, 2008
1:20 PM

Hi!

I am a home sewer and a frustrated consumer of clothes. I don’t know if my comments here are totally off topic, but I thought I’d ask anyway.

I am a size medium in the shoulders, with an extra large chest. If I gain even 5 pounds, my chest gets larger but my shoulders don’t! Same the other way — I lose 5 pounds and my chest gets smaller but my shoulders don’t.

So, my problem — size medium fits me right in the shoulders but the chest is too tight, usually. Size large fits me in the chest, usually, but the shoulders are too baggy.

In reading these grading articles, I see the underlying logic is that if one area gets bigger, all areas get bigger (resulting in my medium – large conundrum).

But why is that the underlying logic? A woman who is a fit size medium in her 20s and 30s doesn’t get larger shoulders as her chest and stomach expand in her 40s and 50s.

I’m just wondering if pattern-making people take this concept into account when they make clothing. I have such a hard time finding dresses and tops that fits, so I’ve just started making my own clothes.

I’ve got the shoulder to bust fit worked out, but now I’m trying to figure out the waist to rearend / stomach to abdomen curves — I’m still getting a lot of bagging in those areas. (This part is purely FYI / chatting, sorry).

Anyhow I love this blog and I’m learning a lot. I have no education in pattern making and fitting, just what I’ve read in books, so I love that I can read what the experts are saying and learn from all of you.

Thanks.

Kathleen
April 14th, 2008
2:37 PM

A woman who is a fit size medium in her 20s and 30s doesn’t get larger shoulders as her chest and stomach expand in her 40s and 50s.
Here we’re talking about human developmental changes. I would agree that while much attention is made of drafting for human development at the lower end of the scale (children’s), pathetically little attention has been paid to the figure types of an aging populace.

I’m just wondering if pattern-making people take this concept into account when they make clothing.

We’re not in charge. Pattern makers can only do as our clients or bosses tell us to do.

I am a size medium in the shoulders, with an extra large chest. If I gain even 5 pounds, my chest gets larger but my shoulders don’t! So, my problem — size medium fits me right in the shoulders but the chest is too tight, usually. Size large fits me in the chest, usually, but the shoulders are too baggy. In reading these grading articles, I see the underlying logic is that if one area gets bigger, all areas get bigger (resulting in my medium – large conundrum). But why is that the underlying logic?

From a previous entry:

For example, consumers have the expectation that if they gain weight, they should be able to grab the next largest size in the sequence and obtain a good fit. Unfortunately, that is an unreasonable expectation due to summarizing of study results.

When mass-marketer manufacturers design their sizing specs, they’re looking at the mid-range of any given size. For example, the average size 2 woman is shorter than the average size 8. Manufacturers design grade rules that encompass those height changes… Manufacturers don’t take a woman of a given size and grade up or down to fit that particular woman as she’d go through the various sizing changes. That would mean they’d only be making clothes to fit someone of a specific height but it wouldn’t make sense to do that as people also get taller in the larger size ranges. It’s an issue of proportion. Most people who are heavier, are also taller. If manufacturers are not highly targeted (such as Lane Bryant) they’re going to shoot for the best sizing bets of the market.

The reason is that sizes are weighted according to aggregates of all measures including height. In other words, a general pattern emerges that the average size 10 is taller than the average size 2; that’s just the reality.

In the above entry, I make the argument that women’s upper garments should be sized like bras, encompassing a greater range of women’s chest sizes. Believe me, I feel your pain. Another entry that may explain is Grading is not morphing

…you can’t grade a regular (or a tall or bbw or whatever) into small, medium, and large etc and then turn around and take the same pattern and regrade that regular into a tall with commensurate smalls, mediums, larges that apply to it. It just doesn’t work that way. Grading can only make an existing shape larger or smaller. You cannot change shapes with grading. Going from a petite to a bbw is changing shapes… Grading only makes an existing shape larger or smaller but it does not change the shape.

deirdre
April 15th, 2008
8:39 AM

Thanks for the interesting information, Kathleen!

If I were a better sewer and pattern maker, I’d open a shop that made clothes to fit the client. I guess people do this already, right? I’m not talking haute couture, just a shop with some fabric and some patterns, and the client walks in and orders this pattern shirt in that fabric and I measure her up and make her the shirt.

It’s got to be better than RTW.

Prol’y cost prohibitive for the average consumer, though.

Again, thanks for the comments and the insights.

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