Making a Diagonal Corset Pattern : Part 1

I’ve made a diagonal corset pattern for an article to be published on Foundations Revealed way back in 2010.

Yup. You read that right. 10 freaking years ago! I’m having a hard time believing it myself but here we are and things are as they are.

Diagonal corset patterns are absolutely mesmerizing and fun to look at especially when made using high contrasting colors. It really makes the lines of the pattern pop like mad.
Absolutely impossible not to notice it so if you want to learn how to make such a statement piece… Continue reading!  😁

This content is not affiliated or sponsored by Foundations Revealed or any other people and businesses mentioned or referenced.

Starting point : Y&N Diagonal Corset

Y & N Diagonal corset advertisement black and white antique

Figure 1 : Advertisement for patented Y & N Diagonal corset

When you look at this 1885 advertisement for the Y&N diagonal corset (Fig.1) you can’t help but ask lots of questions:

  • What does the diagonal cut do?
  • Does it make a corset  more comfortable?
  • Does it give softer curves to the body?
  • Does it stretch more than corsets usually do?
  • Is it purely decorative, or was it a marketing trick of the time that  sells an exotic look?

All those questions may cause you to think, but if the most interesting question is “How do I make a pattern for this style of corset?” then this is the article for you!

Drafting a pattern for a basic, very simple corset, with all vertical seams, that fits perfectly is a challenge by itself,  so drafting a diagonal corset pattern from scratch with no knowledge of that fascinating type of corset makes it a “mission impossible”.

It is hard to draft a pattern when you don’t know what the pattern does and in what way it reshapes the body. It can be an overwhelming experience even for expert seamstresses and corsetmakers. Since I have never owned or made a diagonal seamed corset, I won’t even try to make a pattern for it from scratch.

For this article I will demonstrate how to transform a pattern that you already have into a diagonal seamed corset pattern. This method is intriguing because you can do most of the alterations and fitting on a vertical seamed corset, which is easier to fit, and you probably already have a pattern for that.

The Vertical Seamed Pattern

First, decide what pattern you will transform. It can be a commercial pattern, copy of an antique corset or a pattern that you drafted. For a more historically accurate diagonal seamed corset chose a midbust corset pattern dating from around 1880 to 1900 since most of the diagonal corsets that we know about are from that time.  You don’t have to stay in that time period get crazy and make a diagonal seamed pair of stays from late 18th century, or a modern corset with very narrow diagonal pattern pieces!

Before you start the transformation, make a mock-up of the pattern you chose and fit it. Prepare the pattern and adjust all that needs changing,  because later on you will struggle with fitting the diagonal seamed version of the corset.

I have chosen this corset pattern (Fig. 2) for the transformation since I have already made a corset from this pattern and it dates to the time period when diagonal seamed corsets were popular. It’s also my favorite corset to wear under my Victorian outfits.

Paper vertical seamed corset pattern pieces prepared for corsetmaking

Figure 2 : Vertical seamed late Victorian corset pattern

Since I’ve made this corset before,  I will be able to compare it to the new diagonal corset when it’s completed.

Take the vertical seamed corset pattern that you have prepared and make a toile in a light colored fabric.

Mount the toile on a mannequin (or a pillow if you don’t have a dummy) and fill what needs to be filled with fabric scraps so you get the shape the corset gives to the body. (Fig. 3,4 & 5)

Front side of Mock up of a vertical seamed late victorian corset pattern

Figure 3 : Front of vertical seamed late Victorian corset mock up

Side of Mock up of a vertical seamed late victorian corset pattern

Figure 4 : Side of vertical seamed late Victorian corset mock up

Back side of Mock up of a vertical seamed late victorian corset pattern

Figure 5 : Back of vertical seamed late Victorian corset mock up

Designing the Diagonals

Now let’s decide what kind of a diagonal seamed corset you wish to make. Don’t concentrate only on the front of the corset. You will start from the front with your design but the back is just as important.

Most antique diagonal corsets have a spoon busk, but if you find it too expensive or just don’t like it, use any kind of front closure…  busk, front lacing (do include a front modesty panel so it doesn’t pinch your skin) or make the corset with the center front  closed.

Look at the details and shape of the diagonal cut that you like and work them into your corset. You can copy one antique example or get crazy…it’s good for you. Keep in mind that your design may change when you start drawing on your mock up because some shapes won’t be suitable for the design you had in mind.

Spoon busks look really nice on the diagonal seamed corsets since most of the lines follow the pear shaped curve of the tummy. I also think they balance the design and look elegant, so I took that as my starting point in designing my corset.

Historical Corsets for Inspiration

Look at the details and shape of the diagonal cut that you like and work them into your corset. You can copy one antique example or get crazy…it’s good for you. Keep in mind that your design may change when you start drawing on your mock up because some shapes won’t be suitable for the design you had in mind.

Spoon busks look really nice on the diagonal seamed corsets since most of the lines follow the pear shaped curve of the tummy. I also think they balance the design and look elegant, so I took that as my starting point in designing my corset.

Figure 6 : Page from Price List for Jeremia Rotherman

Figure 7 : Khaki Y & N Diagonal Seam Corset

Figure 8 : Patent-Diagonal Seam/1879/No. 113

Designing on Paper

Before you start doodling all over you mock up, doodle on a piece of paper.
Draw front and back view of the corset you chose on paper and draw your diagonal seam corset design over it.

Need help with drawing? Check out my corset appropriate croquis/fashion figure or check out Pret a Template for loads of fashion figure templates. They come in a range of poses, genders and sizes.

Design no.1

Front with diagonals (Fig. 8) that are very sharp but with no diagonals over the busk. Similar to the corset in Lara Corsets collection.
The back of this corset is actually not a diagonal (Fig. 9). It is one solid pattern piece like the one in khaki golden color (Fig. 7).
I added more bones under the row of slanted bones for more support on the waist and back.

Front view design one diagonal seam corset design idea one

Figure 8 : Diagonal seam design no.1 (Front)

Back view design one diagonal seam corset design idea one

Figure 9 : Diagonal seam design no.1 (Back)

Design no.2

Diagonals on this corset are gentle and the diagonals flows over the front busk. (Fig. 10)
This design is challenging because you need to perfectly match left and right side on your busk. Very eye-catching if made in duo color.
With gentle, more horizontal lines diagonals will flow all the way to the back. (Fig. 11) For this I left the back lacing system in one pattern piece and I followed the diagonal cut on the top to position slanted bones.

Front view corset design idea two

Figure 10 : Diagonal seam design no.2 (Front)

Back view corset design idea two

Figure 11 : Diagonal seam design no.2 (Back)

Design no.3

I call this one up-side-down diagonal corset because the starting point is on the top instead of the bottom, as usual (Fig. 12). Extra wide busk and diagonals flow over the busk.
The back of this corset  (Fig. 13) is also very eye catchy since diagonals flow over the center back too and there are no slanted bones.

Front view upside down corset design drawing three

Figure 12 : Diagonal seam design no.3 (Front)

Back view upside down corset design drawing three

Figure 13 : Diagonal seam design no.3 (Back)

Design no.4 & no.5

A underbust with solid pattern piece over the narrow flexible busk but with narrow diagonal cut. (Fig. 14)
Duo color or even a combination of mat- shiny fabric in the same color would make heads turn.

Titanic era corset or a corset-skirt gone wild, the choice is yours. (Fig. 15)

Front view underbust diagonal corset design four

Figure 14 : Diagonal seam design no.4 (Front)

Front view titanic underbust corset design five

Figure 15 : Diagonal seam design no.5 (Front)

Boning Channels – Internal or External?

Now that you have an idea for how to cut your corset, another important question arises. External or internal boning?
Don’t leave the decision for later because it will affect the look of your corset greatly.

You can spice up a solid color diagonal corset with contrasting color boning channels (add some flossing in the color of the corset on them), tone down a duo color diagonal corset with external boning in one of the colors of the corset, or you can even enhance the duo color with internal boning so the diagonal seams really pop out.

If you enjoy Aranea Black content, consider financially supporting the creation of free corset making content by buying me a coffee.

Designing on the Mock up

Now that we have made a drawing of the design and  decided on all the details, we are ready to draw on the mock up.

Sit in front of your prepared mock up,  take a gel pen or something similar and get “dirty”. If you think you will doodle on your mock up a lot and get lost in the jungle of lines, take a light gray felt tip pen and when you are sure of the design highlight the lines with a bolder color.

Get your pen ready!

Depending on your design you will start from the bottom (designs no.1,2,4,5) or top (design no.3).

Don’t make the first pattern piece a straight line, give it a slight outward curve. (Fig. 16) This is your starting point on how sharp your diagonals will be.

I’ve decided to make the second design example above,  with the diagonals flowing over the busk.

If you are going for the first design (with the diagonals not over the busk), first draw the center front pattern piece that goes over your busk following the shape of the busk + 1cm (3/8″) extra space, then draw the starting point on your mock up.

Vertical seam victorian corset mock up with first design lines drawn on the bottom

Figure 16 : Start of the diagonal seam design

Now that you have a starting point (Fig. 16), measure the desired width of your diagonals.

I drew all my lines freehand (Fig. 17). If you want all or most of them to be the same width, measure and mark before you draw the diagonal.
I let the pattern lead me.

Vertical seam victorian corset mock up with more design lines drawn on it building the desired look

Figure 17 : Front diagonal seam lines fleshed out more

Keep on drawing diagonals (Fig. 18) and as you slowly get to the back it will become harder to make all the pattern pieces the same width.

I fiddled with the back design for some time (Fig.19) before I matched the design in my head to the pattern I was working on.

All diagonal seams drawn on to the front of Vertical seamed victorian corset mock up

Figure 18 : Corset mock up covered with new design lines (Front)

Side view of the late victorian corset mock up with design lines drawn on it

Figure 19 : Corset mock up covered with new design lines (Back)

I decided to make the back lacing system (two piece eyelets/grommets and lacing bones) on a separate pattern piece. (Fig. 20 & 21)
It will not have diagonal seams, as the finished corset will be a dual colored corset and the laces will be in a different color.

All diagonal seams drawn on to the back of victorian corset mock up

Figure 20 : Corset mock up covered with new design lines (Front)

Side back view of the mock up with diagonal lines drawn on it

Figure 21 : Corset mock up covered with new design lines (Back)

Creating the Diagonal Pattern

Dismount the mock up, remove the boning and the busk. (Fig. 22)

Removing busk and boning from the Victorian corset mock up

Figure 22 : Busk & boning removed from mock up

“Butcher” the mock up with sharp fabric scissors following the new drawn lines (Fig. 23).

While cutting, don’t pull the fabric pattern pieces and always keep them on a flat surface.

As you cut, label the pieces so they don’t get mixed up. Simple number or letter pattern labeling is sufficient at this point.

Corset mock up with diagonal lines drawn on laying flat on table ready for cutting

Figure 23 : Corset mock up ready for cutting

Now that all pieces are cut (Fig. 24), it is time to iron them.

While ironing the fabric pieces don’t stretch them, pull them or in any way deform them. Just press and steam, press and steam… otherwise you will distort the pattern and trace a defect pattern piece on paper.

After a lot of steaming and pressing let every fabric pattern piece cool down on a flat surface before handling and tracing.

Corset mock up with diagonal lines cut into separate new pattern pieces

Figure 24 : Corset mock up cut up

Tracing onto Paper

Most pattern pieces will lie flat after ironing but some of them actually won’t and that depends on a pattern you chose to transform.
Dramatic curves on hips or breast area on overbusts will keep the diagonal pieces from lying flat and you will need to touch up those pattern pieces.

First take all the pattern pieces that lie flat (Fig. 25, 26 & 27)because they are easy to trace and need minimal redrafting. Trace all pattern pieces that need no adjusting or minimal redrafting on paper. 

Tracing cut fabric pattern pieces on to paper, start with front center straight line

Figure 25 : Preparing paper for tracing

Tracing cut fabric pattern pieces on to paper, align front of fabric piece with straight line drawn on paper

Figure 26 : Aligning fabric piece on paper

Tracing cut fabric pattern pieces on to paper, Check the traced pattern piece between fabric and paper version

Figure 27 : Checking the traced pattern shape

Don’t forget to trace the seams of the old corset! (Fig. 28)
They will help you to sew all those scary curves correctly and will give you an idea where to place boning channels.

More diagonal seam corset pattern pieces traced on to paper

Figure 28 : More pattern pieces traced on paper

After you have traced all those easy pattern pieces, take the ones that need adjusting.

I only have one stubborn pattern piece that needs to be redone (Fig. 29) because it flows over the hip, and that is where the most drastic curve is on the original pattern.

Corset pattern piece that needs adjustment before tracing it on to paper

Figure 29 : Piece in need of adjustment

The pattern pieces that need a touch up will most likely have an anchor point and that is where you need to alter it.

Instead of forcing the pattern piece to lie flat, figure out where would the extra millimeters go by using a seam of the original pattern. (Fig 30)

On the hip I need to take in a few millimeters but I will draw them back so I don’t lose length or the pattern pieces will not match.

Finding the anchor point on the corset pattern piece in need of adjustment

Figure 30 : Anchor point on crooked pattern piece

Take a ruler and align the old seam so it is straight. (Fig. 31)

Fabric will pucker on the part that has extra.

Fold the extra to make the pattern piece flat.

Pin it or stick a piece of tape over it to keep it secure for the next step.

Straightening the crooked corset pattern piece to prepare it for tracing on to paper

Figure 31 : Pattern piece forced flat for tracing

Take the fabric pattern piece and align it on the seam-lines with its neighboring pattern piece that is already traced on the paper. (Fig. 32)

Measure how much length did you lose and see where the lost length needs to be added, on the top or bottom of the pattern piece for a perfect fit.

Measuring and matching the pattern piece that needs adjustment to the properly shaped pattern piece

Figure 32 : Aligning crooked piece for measuring

Now that you know how much and where to add the lost length you can trace the stubborn fabric pattern piece on paper.
Trace it with the little fold secured. (Fig. 33)

Crooked pattern piece traced on to fabric with the fold secured in place so it's flat

Figure 33 : Traced on to paper

I lost 5mm (1/8″) so I added the same amount at the bottom of my pattern piece. (Fig. 34)

Length of pattern seam lost on the fold, added to the bottom of it and a new edge drawn

Figure 34 : Lost length added & new edge drawn

Retouch any pattern piece that you don’t like the look of.

I gave a gentle curve to this pattern piece (under the armpit) to follow the design of a whole corset that is all about gentle curves. (Fig. 35)

Smoothing out any rough edge lines on the new diagonal seam corset pattern

Figure 35 : Old & new edge line

After all the tracing, retouching and redrafting you should get something like this. (Fig. 36)

It looks confusing on a first glance and I don’t think a lot of people would recognize a corset pattern at first.

Your pattern is ready for a mock up!

Diagonal seam corset pattern pieces done and ready for another mock up!

Figure 36 : Diagonal corset seam pattern done

The Diagonal Mock up

For this mock up, use a light colored fabric in case you decide to alter something on the pattern.

Don’t forget to mark the boning channel lines on your fabric!

For sewing the mock up, I will explain only the most important things in this article because everything else will be explained in detail in the second part of “Making a Diagonal Corset Pattern”.

First off pin the beginning and the end of the seam. (Fig. 37)

Make sure the fabric will not slide on the pins.

Place the pins so they follow the seam line.

You won’t sew over any pins, you will remove them as you sew.

Pinning diagonal seam mock up pattern pieces together

Figure 37 : Aligning & pinning pattern pieces together

Pin the boning channel lines so that they match on both pattern pieces.

Make sure to pin them on the right angle to the seam. (Fig. 38)

Mock up pieces pinned on right angle to seam line

Figure 38 : Pinning on right angle to seam line

Now you can pin the space between the pins that hold the boning lines. (Fig. 39)

You will need to stretch the fabric on some places to get a perfect matching of the seams.

Pin every pattern piece together like this and while you sew remove the pins. Don’t sew over the pins!

Adding more pins connecting pattern pieces on their seam lines

Figure 39 : More pins securing seam lines in place

Insert the busk and make a mock up, back lacing as you usually do.

My corset will have internal boning channels so I made my mock up with internal boning channels, but if your corset will have external boning, echo this on your mock up – it will give you a clearer idea of how will your finished corset will look.

The Finished Mock up

The mock up is ready for some torture!

I made just one side of the mock up so it fits together with one side of the old mock up for a better comparison.

The transformation of the original pattern worked and the diagonal seamed pattern works like a charm. It did take some time to get to the result but it opened a door to many new ideas how to play with diagonal seams on different patterns, not just corset patterns.

Let’s analize

Difference in shaping is minimal (Fig. 40) and we will see if the finished diagonal corset will have a different shape from the original or is the new shape because of the light fabric of the mock up. I felt the same on both sides of the corset so I wouldn’t say that the diagonal seamed corset is more comfortable.

On the diagonal side of the mock up, the torso is not very cone shaped. It curves slightly on the side of the bust and the ribs are a bit rounder, but not enough to say it gives an hourglass shape.

The diagonal seam that flows right at the middle of the bust needs to be taken in by 7-10mm.  I think it is because the fabric I used for the mock up stretches a lot diagonally so I plan to make the corset halfway done and try it on to see if that adjustment is necessary.

Front side of vertical Victorian corset and diagonal seam corset mock up halves worn together for testing

Figure 40 : Diagonal (left) & Vertical (Right) mock up (Front)

The back looks good but the angle of the slanted bones worries me. (Fig. 41)
I plan to angle them more so they rise from the waist toward the back top and not under my armpits.

Back side of vertical Victorian corset and diagonal seam corset mock up halves worn together for testing

Figure 41 : Vertical (left) & Diagonal (Right) mock up (Back)

The side looks nice and I have no complaints. (Fig. 42)
The mock up does wrinkle a lot, but I do believe it is because of the fabric I used. I don’t think it will be a problem on the finished corset.

Side view of diagonal seam corset mock up halves worn together for testing

Figure 42 : Diagonal mock up (Side)

The pattern is ready for the next part of the article!

For my corset I wanted a historically correct pattern but with elements that are not commonly found on antique diagonal seamed corsets.
I imagined it in dual color spot broche coutil (black and white), with a spoon busk in center front but with internal boning. I’m not sure about the flossing… a dual color diagonal corset will look fantastic on its own so I’m not sure if the flossing will be too much. Since I love bows I will make one and “stick” it on the top of the bust…just for a good measure.

Internal boning doesn’t sound so interesting, but triple internal boning does.
I was inspired by Marion’s Winterthur Museum Library article (FR members only) and the 1886 corset with 750 bones. I plan on getting 52 bones into this corset plus four in the back modesty panel. Not even near 750, but a lot more than most of the corsets in the modern day.

The next part will be all about making the corset from beginning to end, decorating it and finally trying it on. I will do a detailed comparison of the new diagonal corset and the old vertical corset and hopefully give some answers on the questions I asked at the beginning.
If you have any questions, observations or comments of you own, feel free to contact me!