Asymmetric Cut Away Side One Piece

Asymmetric Cut Away/Lace Up Side One Piece Analysis

This is a lot easier to do than it initially looks. It's a really sexy style, it has some striking features, but it's nothing overly complicated really. It's even preserved the side darting so there's no need to hide it. 

NOTE: Part of what we all did at Fashion School was look at other people’s high fashion garments and see if we could work out how they were made. This was particularly the case for 3rd year pattern making. The teacher would show us a photo of something from fashion week and give us an hour to make a pattern for it … I loved those challenges. At the end of the hour, the teacher would demonstrate how she thought it should be done and why. Some people out there call this copying or “knocking off” someone else’s design … that’s not what we’re doing here … this is about learning how to make patterns by following a procedure … it’s what we all did and how we learned. I’m not telling you to take these instructions and go manufacture this garment for sale …that is wrong and illegal ... I’m using this design as an example to teach students how to manipulate a block into a pattern that resembles this style (albeit, probably not exactly).


I’m going to base this pattern on the RTW Women’s One Piece 12% Block Set for a Bust size of 92cm, Waist of 72cm and Hips of 98cm. I want to do this to show that the block we start with isn’t important for this type of lesson. Before you start each step, take a good look at the illustration to help you follow the drafting process. At the end of each step your draft should match the illustration.

Step One

Because this one piece is asymmetric we'll need the full width of the front and back blocks. The photo shows it's actually quite a low leg so I've chosen the guideline second from the bottom and highlighted it in red. I think the shoulder strap looks to be about 3cm wide so we'll create our strap guide from mid shoulder to bust point and shorten it by about 2cm ... again this depends on your fabric so perhaps make them a bit longer at first and shorten them in your test garment on the body ... I know 2cm will work for the general swimwear fabrics I use. Mirror the strap on the back block.

Step Two

Next we create the guides for the bandeau section. This is an arbitrary height but at least center it on the bust line or it can look odd. There is also a tendency to try and lower the top line, but the wearer will often adjust it until it feels central (it's a natural thing to do) and hence try to distort your pattern or just feel uncomfortable. Given the size and bust of the model I think it's about 7cm either side of the bust line. I've marked two red lines at this height from center front to the side of where the bust dart is open at the moment ... again you might want to lessen the "side boob" appearance by making it longer, but I'm trying to reproduce the photo. Draw in a guide vertically above the bust point.

I've drawn a blue line from the where the leg line intersects the side seam on the front block, all the way to the center front. Halfway along this line I've squared down to the front leg line. This intersection will be the base of my lower front ring. I've created a similar green line through the back block at the side seam ... this will be the base of the lower back ring.

Step Three

Now the fun part! On the front block draft in your design line (red) from the armhole to the top of the strap and down to the end of the upper bandeau guide. While arbitrary, there isn't really much room for changing the style (unless you're adding other features) so it should look very similar to mine.

From the end of the lower bandeau guide, draft a line (blue), down through the waist at right angles to link up with a point 3cm above guide point on the front leg line ... I've chosen 3cm to have a consistent feel with the strap width and that's about how much it appears to be in the photo. 

On the back block draft in your design line (green) from the armhole to the top of the strap and then down to where the guide crosses the side seam. Now draw a 3cm square into the corner, touching both the design line and the leg line ... I've pulled the square back because I don't want mismatching leg lines.

Step Four

Rotate the upper section of the bandeau to close the side dart. 

Step Five

Draw a 3cm square, centered on where the dart intersects the side seam and rotate it to parallel with the dart. Curve the top of the bandeau to meet the top outside corner of the square. Smooth a line from the lower outside of the square to the side cutaway design line.

Step Six

Rotate the top bandeau section back again. Pull the bust darts back 2cm from the bust point and redraft the darts.

Draw a 3cm square centered on each of the lower corners and smooth off the lines to create your ring stands.

Step Seven 

Add 10mm seam allowance around the entire pattern for both seams and fold over elastic.

In the photo above there are 5 levels of tie straps ... with the central one at about the waist and the top one at about the bust line. So I've divided the block up in two below the waist and then the same above the waist to the bust line (notice that they're not the same between front and back blocks between waist and bust because of the angle of the side seam below the bust dart). These lines represent where we mark the strap positions on the pattern.

Step Eight

Mark the strap positions clearly on the pattern. Add your pattern labels including the name of the pattern, the panel name, how many pieces to cut, the size and the author and revision date. The strap positions are simply folded over strips of binding attached to the edge of the garment ... these create a loop for the tie string, of which you'll need to determine the length of on the body the first time!.

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