Looking at that (and particularly the lower sleeves) basically he's made a T shape and sewn it up, then found his arms were sticking out. That's normal from 54 or 60" wide fabric.
Most fabrics aren't wide enough to go right across your shoulders and down to the wrists in one piece, unless your making for a child, so that extra fabric is a necessity to make the sleeves long enough.
So, someone has looked at it and realised that fitting on a straight bit wouldn't work properly and carefully cut a sort of wedge shape to sew on and thus level the cuffs for him.
The front isn't even buttoned, it's just folded around and belted closed.
The fabrics are wide enough to wrap around the body though so long as the measurements are under 54" or 60".
We can get around that by cutting out along the length, but then you get a seam across the shoulder, which can leak, which is generally not wanted in a waterproof garment.
The T shape is made by basically folding fabric in half. Cut a shallow oval, slightly deeper on the front, in the centre of the fold. That becomes your 'neck hole'. Don't make the hole too big, measure around your neck and maybe add on a couple of inches. Make a loop of string and shape that.
If you want the watchcoat to open down the front, you cut down from the centre of the front of the neck. If you don't then you'll need to slit it there enough to get it over your head which is wider than your neck.
Then you measure the depth of your arms eye; from the top of your shoulder to the bottom of your armpit, giving yourself enough clearance to allow you to move your shoulder joint without being bound.
To do this take an inch tape and wrap over into a loop. 28" is a good starting measurement for an adult male.
Put the loop around your shoulder/armpit and then swing your arm, as though using a bow, an axe, an oar, a spear....if it girds/binds then you need to slacken it off a couple of inches. If it's awfully loose then tighten it up a little.
Once you suss that measurement out, divide it in half. That becomes the depth you
need to cut for the arms. The T bit of the pattern.
It can leave very wide sleeves though, so generally we make gores from narrowing the cuff to something sensible, and adding those onto the underarm to make more give, saving fabric and wasting none of it
That watch coat doesn't have that though, it's sleeves are to my mind too wide at the cuff. Those will catch everything from wind to everything you pass.
Up to yourself on that one.
The next bit is to work out your widest body measurement. Doesn't matter whether that's chest/bust belly or backside. Just the widest measurement.
Then you divide that in half and add on 1" for seams.
That's the
minimum width you need to cut to wrap the I bit of the T around you.
The trick is to give yourself as much on the body as is possible without leaving yourself so short in the arm that you have to add on a lot to make it come down to your wrist.
Take a sheet of paper and pretend it's fabric, have a play with it, then draw it out using measurements.
Ogri the Trog did a thread years ago on making one of these out of wool.
I haven't found the link, but it's about somewhere.
M
