A retro detail

Back in the final days of 2012, I posted this picture of a new top I had made:

It has kimono sleeves, a neckline which curves at the front to a stand at the back (the entire collar is cut on the front pattern piece) and, as a special retro 1950's style detail, pleats from the neckline providing the bust coupe.

Melissa asked for a picture of the pattern piece (which I still forgot to take... it's dark now, but I'll add it tomorrow) but I thought a little tutorial might explain more.

Melissa's comment reminded me I hadn't yet added the picture of the pattern piece. I'm posting a couple now which might be useful. 

And I'm adding a technical drawing (well, a sketch of one) to clarify the design of the top. Please ignore the line cutting the right sleeve in the back view. That's sloppy sketching, not a design line. I really only added a back view to show the back of the neck. Other than that, there are no seams at the back.

This is what the entire pattern looks like:

From left to right: cuff, back, facing, front.

This is the pleat close up: the points which have to be sewn together are marked by the little holes in the paper. You may notice the cut in the paper... When drafting the pattern I wasn't sure about which way to fold the pleat so I couldn't determine the shape of the seam allowance at the pleat. Leaving more than enough material there is a cheat's way of dealing with that (it just makes marking the actual edges of the pleat extra-important)

It is, in fact, a simple matter of dart rotation. And of converting a dart to a pleat. 

This feature can be made on any kind of bodice which has a bust dart and a shoulder seam for, at least, a couple of centimeters next to the neckline (which means it can be used with all bodice-sleeve combinations except full raglan sleeves). It is most often used with shawl collars or cut-on standing collars like mine. I can see no reason whatsoever why you couldn't use this feature with, say, a notched collar or a classic shirt collar but it's less of a 'period' look.

It may be easier to use a sloper because on those, the bust dart ends at the bust point. In a normal clothing pattern, the bust dart is usually shortened, often by about 3 cm. To do any kind of dart rotation, you have to determine the actual bust point on the pattern (and make sure it is the actual bust point on you). Some pattern companies print a bust point and/or the line it should sit on, which is a huge help.

Anyway, take your sloper or lengthen the bust dart on a commercial pattern to the bust point. Copy it onto a piece of paper.

Draw a line from the bust point to the tip of the shoulder seam (picture shows a pattern without seam allowance). If you plan on combining it with a type of collar which has to be sewn on at the neckline, draw this line 1 to 1.5 cm further down the shoulder seam to avoid bulk.

Cut along the new line and the dart and rotate the shoulder section until you've closed the original dart.

The newly opened 'dart' is your pleat. Make sure to mark the points which have to be sewn together with notches and to cut enough extra material at the center of the pleat so it can be sewn into the shoulder seam later. 

When sewing the top, match the notches for the pleat, press the pleat (on the inside) towards the arm and anchor it by stitching in the seam allowance. Then, stitch the shoulder seam as usual.

Because I have made a different, darted version of this top before, I can even show you what the dart rotation did to my pattern:

The original version with a dart from just above the waist at side seam is at the left, the new version (with collar and overlap for the button closure) is at the right.

I hope this is easy to follow. As ever, feel free to ask questions by commenting or emailing and if you use this tutorial and show it off online, please refer to this post. 

If you'd like to make something similar but you don't have a kimono-sleeve pattern to start with, here's how you can alter a fitted t-shirt pattern with a normal sleeve:

Cut the sleeve pattern lengthwise in half (the notch for the top of the sleeve markes the seperation between front and back. Start there and then cut parallel to the straight grain line) and match the pieces to the front and back bodice at the top (usually, the sleeve tops should end up to 1 cm above the tip of the shoulder) and at the sleeve notches. Allow a bit of room (about 2 to 3 cm) between to notches of sleeve and bodice to create ease for movement. 
Draw a curved line from bodice to sleeve. For my tops, I start this line at the waist. 

This is a simplified version of how-to-make-a-kimono-sleeve. This is actually a blend between the wide and the fitted kimono sleeve which needs the stretch of a knit fabric.