The Japanese monpei are working pants constructed in such a way that there is no waste fabric – you cut triangles from the waist area which you use for the crotch. It works – with a few caveats!

This gives you an idea how the pants are constructed. Click here for a link to the original set of instructions. (I’ve added notes and some numbers to the instructions – click here for my additions.)

Here’s what they look like finished.

This is actually my second try – I followed the instructions for the first try – cutting triangles from the “top” of the rectangle panels (3 1/2″ for the back crotch gusset; 1 1/2″ for the front crotch gusset). Because the panels use your hip measurement to calculate the width the waist on my first try was WAAAAY too small.

Fortunately, I had enough fabric left that I was able to start over – this time working with the complete rectangle (because my waist is almost the same as my hips) and cutting a single gusset for each leg (constructed by making the front and back gusset pieces into a single gusset piece). However, I didn’t have quite enough fabric for the legs – I cut 12″ from the bottom of the first try and added them to the bottom of the legs on this second try to give me enough leg length. I was going to do some decorative stitching to make the seam appear to be intentional but in fact you don’t notice the leg lengthening seam so I’ve left well enough alone.

I used rayon fabric I bought in Bali in 2014 (where do the years go!). It’s a lovely weight and drapes nicely. I’d say the monpei turned out rather well. I have to look at some of the other rayon in my stash and see if there’s enough of another piece for a second pair of pants.

I didn’t quite follow the instructions – I didn’t cut fronts and backs of legs separately, I cut single panels for the front/back leg – no side seam. A next pair will have a side seam because I want to add front pockets and they’ll work best if they side of the pocket is incorporated into a side seam.