(The information below is modified from notes taken by Kate)

The pattern these instructions are based on is the 18th century stays pattern from the book ‘Period costume for stage and screen‘, but the principals of adjustment should work on most uncupped corset designs.

Adjusting the garment to fit the models/your own measurements.  This has to be done before dart manipulation on the stand for the bodice.

As the corset pattern is drafted for an average size 12, the pattern must be graded up or down to according to the models actual measurements.

basic block range my natural measurement
Bust 86-91 cm 91 cm
Waist 63-68 cm 70 cm
Nape to Waist 38-40 cm 39 cm

N.B. Whenever making adjustments to the pattern for fit, remember it is very important to maintain the ‘period silhouette’.

A) Adding/Subtracting width.

Slash vertically along the dashed lines and spread or overlap to achieve the desired width.

Make the adjustment equally across all the panels. So if you wish to remove 5 cm from the waistline, 0.5 cm must be removed from each pattern piece (2.5 cm from each side set of A-E panels).

When adding width, place paper behind slashed area, tape in to place and then neaten the lines to accommodate the extra width.

When reducing width, overlap the two pieces the desired amount and tape up, again neatening lines where required.

If even more width is required, an extra panel may added at the back.

B) Adding/Subtracting height (Nape to Waist back).

Slash vertically along the dashed lines and spread or overlap to achieve the desired length.

Slash and spread, or overlap depending on if the height measurement needs more or less.

To adjust nape to waist, slash midway between the bust and  waist measurements.

n.b. When adjusting the n->w measurement you need to consider that this corset is only going as high as the chestline, and so any discrepancy between the block and the model measurement must be considered proportionally.

e.g. If the n->w of the block is 40 cm and the n->w of the model is 43 cm, the adjustment can be reduced to 1 cm as we do not have to worry about shoulders and sleeve fitting.

The shoulder straps would not affect this as their length can be adjusted.

C) Increasing bust-line and back measurement.

To increase the bustline, add the equally divided amount to panel A, B and C. If the back needs broadening in addition to the bust, equally divide the amount to panel D and E.

Adding to the bustline (A/B/C) and back (D/E).

D) Reducing the bustline.

Reduce equal amounts from panels A and B.

E) Increasing the waistline.

Add equal amounts to panels C and D.

If a greater amount of adjustment is needed, slash and flare panels C and D vertically, then add an even amount to the centre tasset.

If you are adding a lot of width, it may be necessary to add a tasset for a more balanced appearance.

F) Checking the seam lengths

Check all corresponding edges are equal in length from the ‘top edge to the waist’.

The corresponding edges should be:

  • Whole length of panel A’s edge joining whole length of piece B
  • Edge from the top to the waistline of panel B, joining panel C from the top to where the tassets start.
  • From the top of panel C edge to where the tasset starts, joining panel D to where the tasset starts on D.
  • From the top of panel D edge to where the tasset starts, joining panel E from the top to the waistline.

The amount below the waistline and the length of the tassets for corresponding edges should also be equal.

Adjust any discrepancies in length by checking your body measurements. When in doubt always use the longer measurement of any pairs as a guide.

G) Add seam allowances

Trace off original draft without boning or hatching lines. On the copied pattern add seam allowances as follows:

Top edges                    2.5 cm
Bottom edges                2.5 cm

Panel A
Centre fold                no seam allowance
Left and right edge        2.5 cm

Panel B
Edge to join A            1.5 cm
Edge to join C            2.5 cm

Panel C
Edge to join B            1.5 cm
Edge to join D            5 cm

Panel D
Edge to join C            5 cm
Edge to join E            1.5 cm

Panel E
Edge to join D            1.5 cm
Open edge(centre back)    2.5 cm

The side seams on panels C and D are larger at 5 cm to allow for alterations at the fitting stage in case extra width is required on the waist.

Panel C (front side panel) pattern peice showing seam allowance, boning and hatch stitching placement

Panel C (front side panel) pattern piece showing seam allowance, boning and hatch stitching placement

After I had finished the pattern I went on to constructing the 18th century corset.

http://sew.ciety.net/costume-making/adapting-the-corset-pattern/