The Thong Back Halter Neck

Girl You've Really Got It Going On!

The thong back is one of those curious things that does and doesn't have acceptance all at the same time. Thongs and G-Strings are probably more popular than briefs as underwear, especially for the young adult market. Thong backed bikini bottoms are the norm in South America and many would have you believe Florida as well. But what happens when you put a thong back on a one piece? Immediately it has that 'tacky' or 'slutty' image. Yet the same thing in lingerie is the height of class and sex appeal. This has been changing slowly and more recently they’re less likely to raise an eye brow.

In my opinion, acceptance is not a public issue, but a personal confidence issue. Many have the confidence to wear something risqué for their partner at home behind closed doors, yet wouldn't dare show themselves in public. A thong hides nothing, and there is no question it can make an average bottom look both a lot worse or incredibly sexy, depending on how the wearer carries themselves. Or maybe I’m reading too much into it?

Cheeky shorts indeed got higher leg lines and exposed more cheek, Brazilians became narrower and bikini thongs developed squarer side seams. Back in 2008 I wrote that I believed it was only a matter of time before the thong back one piece returned from its ill-fated timing of the early 90's. I thought it would take some very risqué high fashion top half styling to lure the public into the concept, but that it could work for the 25-32 year old high-fashion group. This was pretty much exactly what happened over the next 10 years!

The sketch below illustrates the pattern we're going to make. This pattern is based on the Halter Neck One Piece Pattern we created previously (using 12% horizontal negative ease and 0% vertical ease). 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

If you take a look at the Size Chart you will see the difference in gusset length between the one piece and thong for this size is 4.5cm. If you've had a look at some of the other patterns you'll have noticed there is a number of ways to handle this difference. A one piece with a thong back still requires 4.5cm to be removed, but it's really very simple. First we will lengthen the front block by 4cm in order to move the crotch seam back to a more comfortable position. Draw a rectangular guide 4cm long and 1cm wide and place it at the bottom of the centre front line. The 1cm wide represents half the width of the thong strap. Because I'm using 9mm elastic, my thong width is 20mm (allowing for 1mm wrap each side). You could make it narrower (say, 14mm instead of 20mm) by overlapping the elastic, which would be more comfortable, but that's up to your design.


Place a similar rectangular guide above the crotch seam at the centre back ... this represents the same position as you added to the front. Now draw another rectangular guide 1cm wide and 4.5cm long above the previous guide ... this represents the gusset difference.


A thong back also requires a higher leg line. Draw two horizontal guides, the first 4cm above the bottom of the side seam and a second 4cm further above again. These represent the predictable safe leg line positions. You could go higher still if you're that way inclined, but further pattern modifications would be required.

Step Two

Draft in the front leg line starting at the crotch seam. Draw initially vertically upward then curve out to meet the original crotch width and lastly slowly curve out to meet the side seam at right angles. The red line represents the lowest leg line, the orange the highest. As mentioned before, these are not strict boundaries, just predictable ones. I have seen some Japanese Thong Back Halters with a leg hole higher than the waist!


Draft in the back leg line starting at the crotch seam. Draw initially vertically upward then slowly curve out to meet the side seam at right angles. Again, the red line represents the lowest leg line, the orange the highest.

Step Three

Remove unnecessary guidelines. If necessary retrace the front and back panels. Add seam allowance to the pattern based on how you intend to assemble it. I've shown this pattern with 10mm allowance for overlocked seams (8mm to blade plus 2mm off cut) and 10mm allowance for folding over 9mm elastic. If you were to use a binder attachment to apply the elastic and casing fabric to the edge, then you wouldn’t need any seam allowance on those particular seams. Finally, be sure to clearly label your pattern pieces with a title, panel name, garment size, cutting instructions, author’s name, date and revision number.

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