Drafting patterns

· sewing ·

When I started sewing, I never thought that I would have a go at drafting patterns, but that’s exactly what I’ve been doing for the past few days. When you draft a pattern, you start with your measurements (or the measurements of whoever you are making clothes for), and a blank piece of paper, and you create a pattern from scratch. It has always seemed like a really daunting process, but I came across a series of classes on Craftsy.com taught by Suzy Furrer on pattern drafting (the linked class is on drafting a skirt, but there are lots of others), and realised that it’s not as impossible as it seems.

I really like Craftsy classes, and I’ve taken quite a few and got a lot out of each of the classes I have watched. Suzy Furrer is an excellent teacher, goes at a good pace with no waffle (which is important in video classes, as otherwise it gets tedious pretty quickly), and she really knows how to make a complex process seem less intimidating. Drafting patterns is actually an ideal activity for geeks: there’s lots of measuring, some maths and geometry, with lots of rules and well-defined processes to follow.

The idea is that you create a basic pattern (called a ‘sloper’), which is a no-frills basic template of whatever garment you need, which you then use as a starting point to create more elaborate patterns. You make muslins of your sloper and tweak the fit until it is perfect before you finalise it, and that way, you know that garments you draft from it will fit really well.

I actually started with the trouser sloper class (or ‘Pants Sloper’, since Suzy is American), as I need to make a pair or two of long shorts for the summer1. I could easily find a pattern I liked and make that (indeed, I already have the Thurlow trouser pattern, which includes a pattern for shorts which I could easily lengthen), but I thought that drafting my own would be more fun. It’s a really absorbing process, and I was delighted when my finished first draft actually looked like a trouser pattern, and even better, looked quite like trouser patterns I have made successfully. I made up a muslin yesterday, and was amazed that it fitted really well for a first attempt: certainly much better than almost all ready to wear trousers I’ve ever tried.

The idea with a trouser sloper (sorry, I can’t bring myself to refer to pants slopers!) is to fit the body very closely down to about the low hip level (that is, the part of the lower body with the biggest circumference) and then fit the legs more loosely, so that the material hangs nice and straight to the floor. On my first go, the front crotch length was a bit long, so I needed to take a wedge out of that to shorten it, but once I had pinned that out, the fit around the rest of the body was wonderful. However, lower down, the fabric of the leg was bunching slightly awkwardly on the outside of the knee.

This is something that I’ve often noticed on trousers I’ve bought, and mentally filed in the ‘it’s because you have a weird body’ drawer. Thanks to this process of drafting patterns, and thinking about how clothes hang, I’ve realised that yes, it is because I have a slightly weird body, but now I know why it happens, and how to get around it to some extent. The reason that the fabric hangs oddly is that patterns assume that you carry weight fairly symmetrically on your legs. When you draft trousers, you do automatically make the back pattern about 1 inch larger than the front, but beyond that, it assumes that your legs have a ‘standard’ distribution of tissue. The problem is that I have quite prominent quadriceps muscles2 and also carry more mass towards the inner thigh than the outer thigh, so the fabric gets pulled from the back of the leg to the front, and horizontally from the side seam towards the inseam. I then have a prominent calf muscle too (I have Henry VIII’s calves, and suspect I would rock a doublet and hose, sans codpiece), which hauls the fabric to the back of the leg again, and somewhat out towards the side seam. That’s why the fabric bunches up at the outer knee, because it’s trying to change direction abruptly.

I slit the completed muslin up the inseam on one leg, and looked at how the fabric wanted to spread and fall, then experimented with inserting and pinning in panels of fabric in different places. With legs like mine, you can’t really have your cake and eat it unless you always wear extremely wide-legged trousers, so it requires a bit of compromise. My intuition is that trousers want to hang on me slanted towards the centre line of my body, with more fabric towards the inseam than the outseam, so I’ve adapted the draft slightly to allow this to happen. Frustratingly, I’ve now run out of muslin to mock it up, so I’ll have to wait until I’ve bought more to find out whether the experiment worked. It’s certainly exciting: if this works out, the trouser-making world is my oyster!

  1. Assuming we have a summer in the UK this year, of course. ↩︎

  2. I like to believe that this is pure muscle built through cycling, but have to concede that some of it is just cake. ↩︎