Hi everyone - thank you for the nice comments on the girls' halloween dresses and for all the interest in slopers/blocks. I started writing a response to a couple of questions in the comments but it got too long. So am just doing a quick post to answer them here.
Q: What is a sloper?
A sloper (US) or basic block (non-US) is a body-fitting paper pattern that is made for an individual. It has no styling features. It is a template from which other patterns may be drawn to form different garments. A sloper is made from a person's individual body measurements (waist, bust, shoulders etc) and, if sewn into a garment, will look and fit like a comfortable bodysuit. I explained it in more detail in an earlier post here.
Q: Do I make muslins (US) or mock-ups (non-US) of garments from my slopers?
Never for the children's garments because their body forms are simple enough (no darts, for instance) to fit into even store-bought general size garments.
For myself (or other adults), it is a good idea to draft a new sloper every few years or so, or after every major body change, to take into account weight gain or loss or age. After drafting a new sloper, I usually make a muslin of the sloper (or the first garment made from that sloper), to check fit in various important places: the fit of the shoulders, the fit of the armhole (to prevent immodest gaping or pulling, for instance) and the position of the darts. I will not bother with how loosely a garment hangs, or how long the sleeves are, which are not fundamental to the fit of a sloper. Once all the adjustments have been made, that sloper is good for all subsequent garments because the fit will be perfect. So from that sloper, I could draw a sleeveless blouse (and make it as snug or as loose as I want) pattern, and add sleeves which could be as long or as puffed or as flared as I want. A loose blouse and a snug blouse made from the same sloper will both fit perfectly at the bust, shoulders and armholes, for instance because the darts and the slope of the shoulders will be the same for a snug or a loose blouse. Those are what gives a garment a great fit. A dress with no sleeves, a dress with long fitted sleeves and a dress with three-quarter length flared sleeves will all fit comfortably and well because the armscye (the armhole) of the sloper that all three were made from, fits right.
I hope this makes sense. I know it is a funny way to look at patterns if you've sewn from commercial patterns. Drafting slopers and making garments from them are, in a sense, almost like working from the other direction. Or working from scratch.
I wish I could explain this via the blog (wouldn't it be fun to do a tutorial on How To Draft A Sloper?) but it is close to impossible because sloper drafting is such a subjective thing, at least the way we did it at home. So much is done "by feel" and "by look" and not by Math or a formula. I can't teach it. I can barely even explain it to myself when I am doing it. And there is so much I don't know. Just the other day while telling mum on the phone about Jenna's puff sleeves, Mum asked, "did you remember to curve the bottom of the puff?"
Thus began a short discussion on sleeve shapes, which (for puffs, anyway) I always thought were straight lines at the seams and hem and curved only at the shoulder. Apparently not. A slight curve to the bottom prevents drooping of the bottom of the puff. I never knew that. And I found it hard to completely visualize on the phone. Darn it, I wish mum and I were in the same country. She knows so much and I am constantly struck by how absolutely nothing I know about drafting. It's like mum sews dresses and I just sew straight lines and hang rectangles on my children.
But I will revisit this again and again over the next months. I need to sew stuff for myself. I even have a buttery-yellow lineny fabric for a tunic that I must work on sometime soon. So if you are interested, check back again.