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In this article, we'll look at a number of different concepts to identify whether the pattern needs to be adapted:
- to size
- around the hips
- below chest
- chest size
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.
Below is the table of measurements used to design our patterns (the main measurements needed to understand this article).
Waist size adjustment
- Determine the difference between your waist circumference and the reference table waist circumference:
actual waist measurement - table waist measurement
In the next step, you will need to distribute the gap between the different pieces of the pattern. The gap will be evenly distributed on the back and front along the waist line.
- The corrective value to be applied to the pattern - to be divided between the pieces forming the front and back is :
((actual waist measurement - table waist measurement) / 4 ) x reduction rate
If the value is positive, the number of cm will be added.
If the value is negative, the number of cm must be reduced.
Example for a size 38 and a discount rate of 15%
Waist measurement: 68cm
Measured waist: 73cm
Corrective value to be applied to the pattern on the back and front: ((73-68)/4)x0.85 =(5/4)x0.85=1.06cm
Example for a size 38 and a discount rate of 15%
Waist measurement: 68cm
Measured waist: 66cm
Corrective value to be applied to the pattern on the back and front: ((66-68)/4)x0.85 =(2/4)x0.85=0.42cm
Hip size adjustment
For the hips, proceed in the same way as for the waist.
The distance to be transferred to the hip line will be :
((actual hip measurement - hip measurement from table) / 4 ) x reduction rate
The difficulty lies in identifying the hip line on the pattern if this is not indicated.
As a rule of thumb, you can use the waist-to-hip distance from the measurement chart to determine its position.
After correcting the front and back for hip size, please check the assembly lengths on the side line of the different pieces (represented by the red arrows).
Chest adjustment
This is where things get a little complicated. It all depends on the swimming costume model and therefore the pattern.
The best way to get a pattern that moulds to your shape and creates beautiful curves is to make a model with breast darts.
If your pattern has breast darts, you will need to manipulate the darts (position, size, ....), which could be the subject of an article in its own right.
If your pattern doesn't have bust darts, the alterations that can be made will be limited, especially for larger breasts.
Specific back width adjustment
Certain morphologies present the specificity known as "broad back". This is often linked to posture and the retroversion/anterversion of the pelvis.
I recommend changing the position of the gusset first, ...- see the article on adapting the pattern vertically.
But above all, I recommend opting for a pattern with a centre back assembly line like the MILA pattern. This type of pattern makes it easier to adapt to different back curves and achieve a beautiful result.
Other adjustments
Other adjustments are possible and may be of interest - these adaptations are in fact mainly linked to the design of the jersey.
- the width at the inflection point of the gusset/bottom. It may be worth increasing the width at the inflection point to improve the 'secure' feel of the bikini.
- the depth of a plunging neckline
- the curve of the bikini line over the buttocks. This point will be developed in another article.