Pattern Drafting

• Introduction
• Materials
• Determining Critical Measurements
• Drawing the Tree
• Playing "Connect the Dots"
• Seam Allowances
• Oh, Those Pesky curves
• But How Do I Do Panes?!
• Could You Be More Specific?
• Recommended Reading

Seam Allowances

Just who decided to use 3/8" as a standard seam allowance, anyway? I hate that. I've been sewing for years, and I *still* can't accurately eye 3/8". I use a 1/2" seam for everything. I find that easier. If you're comfortable with 3/8", use 3/8", but other wise use 1/2" for this step. This is about the simplest step in the whole process - all you are going to do is draw a second line 1/2" (or 3/8", if you really prefer) out from the line you just drew to connect the dots. To mark the placement of this line, measure 1/2" perpendicular from the original line.(Everybody remember your geometry here - the idea is that a you want to be exactly 1/2" from any given point on the original line. This gets a little tricky on curves, which might leave you thinking, "What does this crazy woman mean, 'perpendicular'? This is a curve!". Well, it's like this: In geometry, the might have told you something seemingly silly about how, for every point on a circle, you can draw one line perpendicular to that point by drawing a line from the center of the circle straight out through the point in question. Well, drawing your seam allowance on a curve works the same way. If this is slightly less clear than mud, you'll want to pay close attention in the next section, where I'll cover the in's and out's of curves in greater detail.)

At any rate, you'll want to make a mark about every 3" on straight lines, and closer than that on curves. Now, play connect the dots again.Easy, huh? Well, there are two tricky bits. First off, you are going draw one new line parallel to each old line. That way, you will still have square corners. Second, the curves on this new line are going to be slightly distorted from the original.

Oh, Those Pesky curves

Ok, lets talk about curves. This is going to involve a little geometry. I'm going to stick to numberless geometry, because I personally don't really like numbers very much. If you are number dependant, you might want to go get a good book on analytic geometry.

First of all, what is a curve? Well, lets say it is any non-straight path from point A to point B with no distinct corners to it. If it were straight, it would be a line and really pose no problems, and if it had corners, it would be a set of short lines. If you treat each of those short lines just like a line, they are no problem either. Well, if you want a paraphrased definition from geometry, a curve is an infinite number of really really short lines that meet nearly straight corners. A curve is also a circle that has been ripped open and pulled out of shape. Let's think about circles for a minute: If you take a circle, and chop off four exactly even pieces from around the edge, you get a square that is much smaller than the original circle. If you take a circle and lop of eight exactly even pieces from around the edge, you get an octagon. The octagon, incidentally, will be larger than the square. If you take a circle and lop off 284 even sized pieces, you get a figure that I do not know the name for. It looks a lot like a circle, but is composed of little lines that meet at angles. Do you see where I'm going here? A curve is just a lot of really short lines all connected. Well, since we know how to deal with lines, we know how to deal with curves too.

>So why do curves throw people for such a loop? Well, if you think of a curve as a curve, and not as a collection of really short straight lines, curves can really mess up some fundamental concepts like 'parallel' and 'perpendicular'. It's also really difficult to figure out the length of a curve. Now, I do realize there are formulas for this. But let's face it, it's really hard to deal with knowing that you need 4.62pi yards of trim. Go ahead and just try telling that to the person at the cutting counter. I've never had it work yet. ;) If the first two points weren't enough, you have to remember that the inner and outer lines around a curve have distinctly different measurements.

The nice thing is that once you have mastered some basic facts and 'tamed the wild curve', as it were, you will be able to use curves to serious advantage when you are sewing.

First of all, let's deal with the idea of 'perpendicular to a curve'. This is a fundamental concept, because you will be needing it every time you deal with seam allowances, or a large applied trim around a curve. Let me start by confusing the issue: there is really no such thing as 'perpendicular to a curve'. You can't have something that is perpendicular to the entire curve at once. You can, however, be perpendicular to a point on the curve. Remember what I said about a curve being composed of a bunch of really short lines? Each line, technically, is one point long. (If you remember your geometry, you might be thinking, "But a point is defined as having no length! Anything with length is a line!" Very good, smartie. Unfortunately, we can't really measure against something with no length physical presence, so imagine that we are using really buff points for this. They've all been very good about eating their spinach and drinking their milk.) So, how do we figure out what's perpendicular to a point? We're back to circles again. A line from the center of a circle that goes right through to the outside of the circle is perpendicular to the point of the circle that it crosses. Well, that's all fine and dandy, but what if you don't have a perfect circle? That's easy - imagine the circle. I'm not kidding here. If you imagine a circle whose edge meets the exact point (and only the exact point) on the curve that you want the perpendicular to, then the line perpendicular to the point that the circle shares with the curve is also perpendicular to the curve.

'K? So does that help you draw your seam allowances right? No? Ok, fine, let me put my money where my mouth is - literally. If you have access to american currency, then you'll find that you have access to a dandy little seam allowance estimating tool. Grab a dime. Now, look at the 'tails' side of the dime. See that torch in the middle? It's about centered on the dime. If you were to draw a line straight through that center torch, it would come out of the dime at the left edge of the last 'S' in 'states' and right off the lower left corner of the 'D' in 'dime'. So, if you have a curve, and slap that dime down on it so that the edge of the 'S' lines up with the curve somewhere, without overlapping more than a that little bit of the curve, and the you draw a dot there, and just to the left of the 'D' on the other side of the dime, and then you connect those two dots, well, you've just found a line perpendicular to the curve at that exact point. Now, if you were to do this a bunch of times, you'd have a bunch of lines perpendicular to various points of the curve. A dime is not far off from 1/2". So if you connect all the 'D' side points, you'll have a seam allowance. (Now, you have two options, You can either keep a dime next to your drafting area for the rest of your life, or you can get good at estimating 1/2" perpendicular to a curve. I recommend the later. As long as you're not grossly off, an estimate is usually good enough, and it's much easier on your nerves. But I thought I should include complete instructions for how to do this, so that I don't get five zillion pieces of email asking me what I mean by, 'perpendicular to a curve".)

Now, about the rather troublesome task of estimating the length of a curve: This is easy. Ignore formulas. They really only exist to cause you to fail geometry classes. Get a piece of yarn. Lay the yarn neatly, but smoothly, along the actual line (never use the seam allowance line for this! They are different) of the curve that you want to measure. Mark the starting and ending points of the curve on the yarn. Now straighten out the yarn and measure that. Easy, huh? Well, what did you expect? You certainly don't use a yardstick to take your waist measurement. It's the same idea here. It's hard to measure a curve, but it's easy to measure something straight. Pi is not my friend (unless it's apple pie, and what that does to the aforementioned waist measurement is not particularly friendly either). It's a rather nasty little decimal, and most people at the cutting counter get rather flustered by decimals.

Now, what if you need to make two different curves match in length? This is an important idea, since most period garments were shaped at the seams. A woman's doublet, for example, has two pieces on each side of the front. The ones on the side have a sharp curve just above the underarm. (This is to bring the top of the doublet in where the corset ends and the amount of person the fabric has to cover generally decreases sharply.) Well, remember that measuring string? Measure the edge of the piece with the sharper part of the curve to it. You will need to note where the curve starts. (Usually, the curve "starts" at the end of the longest straight line on the piece. For doublets, you'll be marking up from the waist.) Now, use that string to draw out the edge of the corresponding pattern piece. If you use a cardboard cutting board to do your drafting, this is easy. Pin through the string, through the paper, and into the board. You'll want to pin the string straight up until you hit the start-of-curve marking. From there, you will make a gentler curve. Use the length of the string to tell you when to stop drawing that gentle curve. How do you know how gentle to make this curve? Well, unfortunately, this is where trial an error and experience play into things. But you should, primarily, have all of the information you need from the original critical point tree that you drew. From there, you'll be doing a little experimenting with cutting pieces, pinning them together at the seam line (again, not the seam allowance line), and holding them up to yourself or your intended victim to see if everything is working out all right. After a while, you start to develop a nearly psychic understanding of the zen of matching curves.

The last thing to realize about curves is that the line that makes the tightest part of the curve is shorter than the line that makes the looser part of the curve. That is to say, the inside of the curve is smaller than the outside of the curve. (I just hate saying it that way, because you might get the idea that the inside of a curve is on the seam and the outside is on the seam allowance. In fact, 'inside' and 'outside' of the curve are not at all related to 'inside the pattern' and 'outside the pattern'. Inside is the tighter one. Always. No matter where it is. Got that?) So why is it so important to know that? There are a couple of reasons. The really obvious one is that Elizabethan costuming involves a lot of trim. I mean, gobs and gobs of trim. So what happens if you want to put trim around the curved bottom of a skirt? (Yes, the bottom of a skirt is on a curve, because of the bumroll. Think about it.) Well, if you don't use a flexible trim, you're going to have to be careful. You'll always want to sew it around the outside of the curve first. When you sew down the inside of the curve, you'll get a lot of little pleats. If you sew the inside first, it won't go around the outside of the curve at all. I realize that this is a sewing concern, and not a pattern drafting concern, but it is definitely something to know about curves. The thing that is a pattern drafting concern relates to types of flounces. A flounce is a type of ruffle that is created by sewing together a bunch of wide curved pieces (to make a spiral, basically), and is then applied to a flat piece of fabric with a line of stitch along the inside of the curve. Since the outside is longer, it forms a nice soft ruffle without gathering at the top. Elizabethan costuming would not, at first glance, seem to use a lot of flounces. But if you think about it, the skirting along the bottom of a bodice or doublet is, in fact, just a very tailored flounce. It relies on a carefully controlled ratio between the inside of the curve and the outside of the curve to fit exactly over a woman's skirts or a man's slops. How do you know just what the curve for skirting should look like? Unfortunately, this is another experience and trial and error issue. There is a general rule that makes it easier - the tighter the inside curve is, the longer the outside curve will be. If I were going to make skirting for one of my bodices, for example, the sharpest curve would be at the side of the waist, because the skirting not only has to go over the bum roll, but has to get all the way around from the front of me to the back of me.

Some of this takes experience to learn to judge, but that should not be intimidating. Everything is a learning process, and this is why we draft patterns on cheap stuff and, when all else fails, make mock ups.

But How Do I Do Panes?!

Remember a few steps ago when we started chopping up our imaginary sleeve pattern? Panes are basically the same thing, but we do it twice in a row. Draw out your basic pattern. Again, we'll use a sleeve as an example. (I apologize. I have sleeves on the brain today. I'm working on a pattern for one in my free time, so bear with me.)

Ok, we have a basic shape for a really flat arm, right? Right. We cut that along the most critical lines and spread it out to get a poofy sleeve pattern, just like before. We trace around that, just like before. Now, we're going to do a little more marking and cutting, but we are going to do this on a separate sheet of tissue. Place the second sheet over the first. (Why? Well, because most of the time, when you make anything with panes, it's not just panes; there's also fabric behind the panes. So you want a backing pattern and a pane pattern. With me here? Good. We're making both at the same time.) You must be able to see the outline clearly though the top sheet of tissue for this to work. If you can't see it, try going over the outline (on the bottom sheet of tissue) with felt tip marker. Now, you need to figure out how many panes you want, and if you want them right next to each other, or slightly separated. (Or right next to each other at wrist and slightly separated at the top, which is what I happen to be doing with that sleeve that's on my mind at the moment.) Now, you're going to have to do some math. I know, I know, I promised to stay away from actual math, but this is going to be easy stuff. Go get the calculator, it's division time. If the top and bottom of the piece have very different measurements (and they almost always will) you'll need to make tapered panes. It could be worse. You wrist could be as large around as your upper arm, and that would just be awkward. Now, divide the measure right across the widest part of what is generally the top of the piece by the number of panes you've decided on. Can't decide on a number of panes? Well, play with your calculator for a while until something strikes you. I tend to like 1 1/2" - 2 1/2" panes, myself. If you divide the measurements by one of those numbers, it will tell you how many panes you wanted in the first place. Math can be so helpful sometimes.. Note: you really don't want to make a 2.35235" pane. You'll loose your marbles. Try not to shoot for anything less than 1/4". Note 2: Think: are you going to be adding piping to this? Will that add width? (Hint: the answer is 'Yes'.) Then you will need to remember to take that extra width from the piping *out* of the final measurement of the pane. Since piping for panes will seldom ever be more than a 1/4" twist piping at best, I usually just subtract the width of the piping (sans flange measurement) from my standard 1/2" seam allowance. Then when I sew with the full 1/2" seam, everything gets pulled neatly into place and I don't have to worry about it.

Anyway, back to math class. You've figured out how many panes you want. You've come of with a pane width that is a reasonably sane fraction. Now, go do the same thing with the corresponding small measure at the bottom. If you're working on a long piece (like a sleeve), do this again at the middle. You should be coming up with a number for the wide of each pane, total number of panes, and a number for the space between panes (if applicable). Now, we're going to do some marking. Draw a line straight across where you took each set of measurements for the pane math (widest part of the top, small part at the bottom, middle if used). Starting at the left side of the top line, measure in half of the standard space-between-panes distance. Make a mark. Measure over the distance of one pane. Make a mark. Measure over the full space-between-panes distance. Make a mark. See where we're going here? Good. Repeat ad nauseam. Do the same thing for the rest of the lines and their measurements. In every case, the space between your last end of pane mark and the right edge of the piece should be one half your space-between-panes measure. Neat, huh?

Now, you need to connect those marks. If any of the lines cross, you're being silly and connecting the wrong marks. Jeesh. All connected up right? Good. Almost done. Now, cut all of these silly panes out. What you have, right now, are panes without seam allowances. This is not good, because unless you are working with leather (and not always even then) you'll want to construct your pane as a two-piece tube. Often, you'll have piped edges in there. It comes out looking right spiffy. So, slap all the panes onto *yet*another* sheet of tissue. Trace your seam allowance around them. If you're using piping, do what we said earlier about using a scant seam allowance to make up for the width of the piping.

Yippee! You're done! If you think you know why they're called 'panes' now, just wait until you try sewing and turning the little buggers!

Could You Be More Specific?

Yes. I could. In fact, in several sections of this web site, I have. If you are looking for instructions for drafting a specific kind of garment, check the appropriate section in the site index. If they're not there, email me asking if I'll put something up for it. *Do*Not* email me anything like, "My name is XXXX, and I wear a size 3/4, I've got a 34" bust and a 24" waist, could you, like, draft me a pattern for a full late italien ren gown, overdress, sleeves, all accompanying undergarments, and one of those really neato headpieces, oh, yeah, and I need it by next week thursday for a school play." I will just become cranky. I do do full pattern drafting, but don't rely on the goodness of my heart for it - offer money.

Recommended Reading

"The Art of Fabric Manipulation" - an absolutely wonderful book that will tell you everything you need to know to determine the amount of fabric you'll need for the exact right type of pleat, gather, pucker, or whatever else you might want to do. And it will show you how to do it correctly, and the final results with any of 17 subtle variations. Highly recommended.

There are also a bunch of commercial pattern drafting books out there. None of them are geared towards pre-1900 costume in general, that I know of, but they might be useful.