You would think that with the success of my self-drafted moulage, that drafting a commercial sloper would be easy? Well, no. Maybe it’s just me… but I have been really struggling with what should be a “simple” task. Let me elaborate:
Drafting Personal and Commercial Patterns Are Vastly Different Processes
Different and Multiple Measurements
If you are following a step-by-step tutorial that provides you the measurements you need (with maybe just a few personalised), then it’s not too hard to produce something decent. You also have the ability to test that pattern to make sure that it works. Often in the cases of this style of tutorial, complex maths and standardised measurements has already been calculated for you. And this is what I am interested in; I want to know what those standardisation are and where they came from. Having a thorough understanding of why certain measurements are used – and for what body parts – can help me draft better fitting patterns.
More importantly, I need to know if these measurements should be adjusted between sizes. There is a significant difference of knowing one’s own bust measurement and the ten or so bust measurements of each pattern size you plan to produce for sale. On top of that other body measurements change as well – the side seam lengths might change between sizes for example.
Different Measurement Locations
The ASTM provides an averaged measurement of women’s sizes, calculated from a number of women. It’s highly useful to know what measurements the general population has.The current ASTM documentation provides just over 60 different body measurements. 60! And yet, it’s not enough. Different drafting methods will use different body points to calculate from. For example in Suzy Furrer’s Pattern Making Basics: The Bodice Sloper class on Craftsy, Suzy uses a measurement from the centre front neck point to the bust apex. Meanwhile, the ASTM documentation provides the measurement from the side of the neck to the bust point. You can’t just do some maths and calculate the other length as the body is 3D shaped – meaning that it’s not a direct line between bust apex and neck but rather a series of subtle dips and curves.
You will encounter the same problem with almost every drafting method; each author likes to use their own measurement locations.
Sometimes Measurements Just Don’t Add Up
So why am I so frustrated with the process? Well sometimes your measurements just don’t add up. It can take a lot of time, and trials, to figure out why. Let me give you a proper example:
The picture above is my self-drafted commercial sloper in size 00 (see our pattern sizing). I’ve included three darts radiating from the bust point – a mid-shoulder dart, an armhole dart and a side dart. I’ve also included a simple waist dart. By the way, this basic sloper drafting method is taught in Patternmaking Basics: The Bodice Sloper by Suzy Furrer (read our review). Overall, the sloper looks pretty decent; usable. Not exact, but more on that later.
This sloper draft didn’t start off looking as good as it does now. Following Suzy’s instructions carefully, I produced a sloper that clearly had a significant flaw: the armhole is way too small.
I checked the side measurements and they consistently came out correct. Even if I was to remove the side dart, I would still have a armhole that measured about 2.5″ too short. So why wouldn’t this drafting method work for my commercial sloper and yet work for my personal moulage? It took me a while to realise that the ASTM measurements were taken to the crease of the underarm, whereas Suzy directed personal measurements to be taken slightly under the underarm to give necessary ease. After all, you don’t want your sleeve to come up that high or it’s just uncomfortable. This difference is measurement means that at least 1″ could be removed from the ASTM armhole measurement. I was still left with at least an inch unaccounted for.
Since I couldn’t easily lower the armhole further, I realised that the extra length must come from the curve of the armhole. In the above picture I compare the general shape of Suzy’s size 8 sloper and my size 00 sloper (I increased size of her 8 for easier comparison). Simply increasing and decreasing a picture in this way is risky as it distorts the actual measurements used, but it was enough for me to compare the general shape of the armhole. As you can see, Suzy’s armhole has a much smoother curve all over, whereas my armhole curves more dramatically near the underneath of the arm. One of the reasons for differences in measurements.
I’ve now come to the point of testing my commercial sloper… except I can’t. This is one of the biggest differences between drafting a personal sloper and a commercial sloper; whether or not you can test and finesse your final product. Everyone’s body is different and a commercial sloper is designed to try to fit all those different bodies… at the same time. I can’t just ask people to test the sloper as each tester will report back with fitting issues of some kind.
So I have decided to take a slightly different route in my testing; I am planning to compare it to a thoroughly time-tested pattern. More specifically, a vogue pattern. Vogue pattern 1004 is called Misses Fitting Shell. It’s essentially a sloper that has been designed as the first step for individuals to create personalised slopers and moulages. It allows you to fit and adjust a pattern rather than draft a pattern from scratch.
I don’t plan to use this sloper to draft my own patterns. Firstly because this pattern uses different measurements than what I want to end up using; I want to produce patterns generally for D cup sizes, whereas Vogue generally covers only B cup patterns. Instead I will study how my sloper compares to that of a current commercial sloper and adjust as deemed fit.
From there I will be able to finally start working on my own patterns. Finally!
Is it hard to draft a sloper? If it’s a personal sloper, then no; you have all the measurements that you need handy. Plus you can test your pattern once completed. If it’s a sloper that you plan to use for making patterns to sell; then it is a bit more complicated…
What has been your success (or struggles) in making a sloper? Have you ever drafted patterns from scratch? Is it something you are interested in?