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This article is aimed at the more experienced and will require some knowledge of pattern making. It focuses on patterns such as 1-piece swimwear, bodysuitsOther pattern adaptations are possible, but will be covered in other articles.
This article looks at a number of different concepts to help you identify whether you need to adapt :
- the vertical pattern: upper torso and crotch
- the position of the bottom of the trousers/between the legs.
The content of the article is dense ... feel free to pause, reread it, ... test it.
These are basic concepts to be understood when designing stretch garments (with the notion of tension lines).
Table of measurements
Before talking about fitting, you need to know the table of measurements used to design a pattern, and this applies whatever the garment to be fitted.
For all garments such as swimwear, bodysuits, knickers, etc., this is essential. The garment is designed with one or more reduction rates for a snug fit.
Below is the table of measurements used to design our patterns (the main measurements needed to understand this article).
We will offer you two methods
- Une première méthode très précise qui dissocie l’ajustement vertical du haut et du bas du buste
- and a second, simpler and more general method
1- METHOD 1 (detailed precise but more complex)
1-1 Upper torso vertical adjustment
To do this, we are going to look at the :
- Waist-to-chest distance
How much will I have to increase or reduce the verticality of the upper torso?
Compare the distance measured with that listed in the table of data used to design the Idonim patterns.
If the distance measured is greater than that on the size chart -> the vertical pattern between the waist line and the bust line will have to be increased.
If the measured distance is less than the distance on the size chart -> the pattern will have to be shortened vertically between the waist line and the bust line.
How can I shorten or increase the verticality of my upper torso?
increase
reduction
1-2 Ajustement vertical de l’entre jambe
To do this, we are going to look at 2 other measures:
- Waist to hip distance
- the distance between the waistline and the narrowest point of the crotch
The distance between the waist and the hips (A) is often difficult to measure for many of us. Yes, where is the hip line? This is often a source of error. We will consider that the hip line is the line or the circumference is the largest (e.g. passage to the tip of the buttocks).
In our case we are also interested in the distance between the waist line and the narrowest point of the crotch (B). This distance should be measured with a tape measure held vertically. Do not place the tape measure along your body to avoid bending it! If necessary, ask for help. To do this, sit down on a chair or a flat, hard surface.
How much will I have to increase or decrease the pattern in verticality?
It is necessary to know the data/measures used in the design of the pattern. This is where the story gets complicated. Not all the data and specifications are published with the commercially available patterns.
I'll make it short, you'll have to make a rule of three between the measurements you've taken and the measurements of the pattern at your size.
Calculation to be made :
waist - hips table reference - (B/A x waist-hip table reference)
The result is positive -> the pattern will have to be shortened in verticality
The result is negative -> the vertical pattern will have to be increased by the same amount
The distance to be increased or decreased will be distribute vertically at the level of the crotch.
How can I shorten or increase the verticality of my crotch?
If you need to increase or decrease the verticality, you will have to retrace the area of the bottom of the breeches, taking care to respect the width of the gusset at the narrowest point (inflection point between the front and the back) but also not to reduce or increase the width of the bottom of the breeches at its extremities
1- METHOD 2 (simpler but simplified, general)
L’ajustement sera uniformément réalisé au niveau de la ligne de taille. Pour chaque écart de 5cm de stature, ajoutez ou retirez 1,5cm au niveau de la ligne de taille. Cette valeur est ensuite répartie uniformément de part et d’autre de la ligne de taille.
SI votre stature nécessite d’augmenter votre patron de plus de 4 cm vous pouvez répartir l’augmentation sur la ligne de taille et une ligne au-dessus de la poitrine afin d’homogénéiser l’adaptation et de ne pas la concentrer sur la ligne de taille.
Conclusion
If you need to reduce or increase the length of your torso, make this change first.
Concernant l’entre jambe le plus difficile est de souvent déterminer comment sera répartie l’augmentation/ diminution entre la correction en verticalité. Une notion primordiale est la position du point d’inflexion. Je vous conseille vivement de consulter l’article concernant l’adaptation – partie n°3
If you need to adjust the pattern for this reason, adjust the position of the inflection point first and only then the vertical adjustment of the crotch.