English 
French 
What is patronage?
This involves drawing the different parts of a garment flat on paper or in CAD format.
Would you like to make your own made-to-measure pattern or modify a pattern to suit your body shape? Then pattern making is for you!
This article isn't intended to be a course in pattern making; far from it ... but to give you a few useful tips and ideas to help you get to grips with pattern making.
Other articles will be specifically dedicated to the different techniques or steps involved in modifying a pattern.
The necessary equipment
You will need :
ruler, pencil, eraser, paper, thin paper for tracing, calculator ...
Size chart & measurements
Understanding a size chart and taking measurements are the 2 keys to understanding pattern making.
Lingerie and swimwear sizing charts are very detailed. We have selected the main measurements:
- waist circumference
- circumference under the breast, circumference of the breast to determine the cup size
- hip circumference
- stature
- the length of the forks
Idonim measurement chart
Other measurements are very interesting to analyse; they are linked to morphology (non-exhaustive list):
- width between breasts
- back width
- retroversion or anteversion of the pelvis
Mathematics and geometry
A pattern is simply a representation of a 3D garment on a 2D plane.
The volume of a part is obtained by forming clamps that can be moved, modified, etc. or surplus fabric, etc.
Patternmaking therefore involves drawing a pattern or modifying a basic pattern or block to adapt it to your measurements/morphology.
A knowledge of geometry and mathematics is an asset. But knowing the characteristics of the textiles and supplies that will be used to make the garment is another. And the latter is very often forgotten! Yes, I know, I'm insisting and repeating myself...
Design data
To adapt/modify a lingerie or swimwear pattern, you need to know all the design data - which is rarely transmitted with the pattern, such as :
Benchmarks :
The markers will help you identify the position of strategic lines. The main ones used regularly are :
waistline
under-chest line
Chest measurement line
inflection line between the front and back*.
tip of the breast or apex
centre front axis
mid-back axis
* These lines or markers are not systematically represented on our patterns, as they often interfere with the understanding/reading of the patterns. However, they are very useful throughout the technical drawing design process.
The discount rate(s) applied to the design of stretch garments, ...
This is the reduction rate applied to the measurements in the size table. The reduction rate can be horizontal or vertical.
It is directly linked to the fabric used/prescribed, to its extensibility.
>>> Set your frame of reference: the axes, the "zero". - the zero can be a point or an axis.
Example
What is a pattern designed with a horizontal reduction rate of 12% (for example)?
For a French size 36 the waist circumference is 64cm
The waist measurement shown on the pattern will therefore be: 64 x (1-0.12) = 64 x 0.88 = 56.3cm
You could say that the stretch fabric will stretch by 12% to fit the body.
If you use a fabric that doesn't stretch enough, the garment will be too small!
Please note: There are a number of subtleties linked in particular to voltage lines but also ... the reduction rate(s) can be applied uniformly across the pattern; this is what has been done on the graphical example above. However, for technical reasons relating to voltage lines and the location of anchor points, it may be possible to modify the reduction rate on certain points or lines.
The stretch characteristics of the fabric
The nature of the fabric and its bounce rate will have an impact on the fit and should therefore be taken into account when designing the pattern - Read the article 'what is stretch fabric?'.
For all these reasons, it is important to follow the list and recommendations attached to each pattern.
What is a block?
Perhaps you know what a bust pattern is? It's a pattern of the flat bust at actual size for a height chart. It represents the person at actual size. You can therefore make the bust, leg and .... patterns to your own measurements.
I'm not going to write an article on how to make a life-size bust, as there are already plenty of articles on the subject on the internet.
The result is the full-size block for a given size, or the size of the block if you are making a made-to-measure pattern. This block is the basis of the pattern-making stages in the ready to wear but also sectors lingerie and swimwear.
What's special about the lingerie and swimwear sector? extensibility
It will therefore be useful to create one or more blocks including the extensibility rate(s)! especially for reasons of reproducibility if the same reduction rate is used.
I strongly recommend that you make one or more prototypes to validate the block you have created.
Only once the block has been created can the technical design of a garment begin!
General
Never add sewing values before all the pattern-making and garment design stages have been completed.