The Merits of a Basic Fitting Pattern
by Karen Howland
from Threads #79, pp. 48-52
When I started out as a custom dressmaker, I needed a way to simplify the fitting process. So I turned to patternmaking, where I learned how to draft basic fitting patterns, called slopers, and create different styles of garments from them. I was excited about using slopers to make my own patterns, as designers do. But since my students work with commercial patterns, I wondered if I could use what I'd learned from making slopers to speed up the alteration process. The clear connection I finally saw between a sloper and any existing garment pattern surprised me with the speed and elegance it offered as an alteration technique (whether your garment or figure is simple or complex), and with how much it clarified the entire fitting process. But to make sense of it, you need to know more about slopers.
Sloper: a "second skin"
A sloper fits the figure it was drafted for with only the minimum room needed to breathe and move (called wearing ease), but without design, or style, ease—or seam allowances. It's the most snugly fitted garment you'll ever wear, and as such, is almost like a pattern for your skin. In fact, the skintight cloth covers of commercial dress forms are made from slopers, drafted from the measurements of the so-called "ideal" figure the garment industry aims to fit.
If you've ever fitted a pattern company's basic bodice and skirt to yourself, you've taken another route to getting a sloper: remove the seam allowances from the altered pattern and there's your sloper. (You've also discovered exactly how you differ from the company's "ideal" figure, represented by their basic.) A complete sloper, from which a patternmaker can draft almost any style of garment, includes a darted bodice front and back, a straight skirt, and a set-in sleeve.
Of course, many garments don't resemble slopers at all, once design ease and fashion details are added to them. But virtually all garments that hang from the shoulders (as do most "tops") will match the sloper they were drafted from more or less exactly in the shoulder area (allowing for current trends in shoulder width and pads). Likewise, most well-fitted "bottoms" match their "parent" skirt sloper in the waist and high hip.
It's important to understand that no matter how you get a custom-fitted sloper (whether you alter a company's basic fitting pattern, drape or draft your own, or have a computer generate a fitted pattern from your measurements), once you try it on and perfect it, your sloper is a record of what fits you. Any path to this destination should result in the same basic outline and amount of dart shaping.