This manipulation is performed for people with a difference in size between the upper and lower body. This is particularly true for V-shaped or A-shaped figures, but many other cases are compatible with this method.
Basic equipment to perform a transformation
To transform a pattern, it is advisable to have :
A parrot rule
A graduated ruler
A support sheet
A pair of paper scissors
A fine point criterion/pencil
Let's start by defining the following terms:
The upper part of the bust is more developed than the lower part. The build, shoulders and chest are wider than the hips.
The lower part of the body is more accentuated than the upper part of the bust. The hips are wide and the buttocks are stronger, while the chest is small and the shoulders quite thin.
If, when reading the measurement chart, you notice that your waist, chest and hip measurements do not correspond to a single size but to several, then you will have to navigate between the sizes of the pattern in order to obtain a design perfectly adapted to the curves of your body. Thus, it is possible to adjust dresses, trousers and suits with fitted cuts, to your own morphology.
As for the very loose models, no modification is necessary. The main measurement to take into account is the part that fits the body the best. The loose part of the model will be enough to fit the rest of the body.
The work is done on the side line of the pattern. The example given is for a dress. But the technique is identical for any other model.
Measure your chest, waist and hip measurements. Compare the values found with the measurement chart. Choose the size for your chest and hip circumference.
If the pattern consists of cut-outs that split the side seam into several parts, then join the parts before making the change.
Using a felt pen, find the different lines corresponding to your morphology, by navigating between the sizes of the pattern. For the bust, select size X, and highlight the neckline, shoulders, armhole, and side, stopping before the waist. For the bottom, select size Y, and highlight the rounded part of the hips going down to the bottom, then continue along the hem.
Connect the 2 lines by the size in a harmonious way. It is advisable to use a modeler's ruler also called "parrot" to trace this part.
Chest size: 88 cm corresponding to a 38.
Waist: 64 cm corresponding to a 38.
Hip size: 101 cm corresponding to a 42.
Chest size: 96 cm corresponding to a 42.
Waist: 75 cm corresponding to a 42.
Hip size: 97 cm corresponding to a 40.
Once the transformation is done, it is important to check that the assembly lines of the different parts measure exactly the same length.
Note It is also possible to scale between 2 plots, if the measurements do not correspond to either an X or a Y size.
Variant of the method
This method can also be applied to specific parts of the pattern, when you want to make a very slight modification. You will have to increase or decrease the pattern of the part to be modified and come to recover the pattern of another size.
Here is a non-exhaustive list of existing possibilities:
Increase/reduce the length of a garment.
Increase/reduce shoulder length.
Increase/decrease neck width.