Guide to Specifying Seams on Tech Packs

The 3 ways to specify seams

Let’s suppose we designed a parka, and we want a shoulder with a strong seam that has a clean finish on the inside and a topstitch. How would you explain that?

First point: If we do not specify this seam to the supplier and we only send a drawing of the garment (see flat sketch 1), it is most likely that they will make a felled seam with an overlocked edge and a basic topstitch (see seam C100-3 + SE). And that is not what you want!

If you have been working in the apparel industry for a few years, you know that you need to be more specific. So, you need to specify that seam with more detail… How do we do it?

There are 3 resources to explain the garment assembly: text, pictures, and seam sketches.

Resources: properties, pros, and cons

1. Text

  • (+) It is easy and quick to make
  • (+) It takes up a small space on the sheet
  • (+) It consumes a light database space
  • (-) The name of the seam might change, depending on where you live > this leads to interpretation problems
  • (-) Language (1): interpretation > the text is usually in English > the fashion designer or product developer and the person receiving the tech pack must speak a language that is often not their mother thong > higher chances of misunderstandings
  • (-) Language (2): translation > if the factory is in a country where English is not the native language, the text is usually translated into the native language > so, there is an extra step in the cycle

2. Pictures

  • (+) It is easy to read and understand
  • (+) No translation is needed
  • (-) We sometimes don’t have the photo that we need.
  • (-) We don’t always have the photo of both sides of the seam > the structure of the seam is not clear > if we show only the outside, there may be different interpretations.
  • (-) They are much heavier than text and diagrams > the file will be heavier
  • (-) They take up a lot of space on the sheet
  • (-) The image must have a good quality (appropriated light, well-focused, etc.) to appreciate the seam and stitches

3. Seam Sketch

  • (+) No translation is needed
  • (+) Both sides of the seam (and even the inside) are visible
  • (+) Their data size is light
  • (+) They take up relatively little space on the sheet
  • (+) They are the most specific > their structure, stitch, and topstitch types are clearly defined.
  • (-) Interpretation: Some designers need help to visualize the diagram.
  • (-/+) Time: if you have to draw them every time, it takes longer than the text or photo > if you use our seams gallery, it only takes a few seconds to add them to your tech pack (copy and paste).

Now the next question is, which of these resources work better?

The least effective (though it is the quickest) is to send a simple text describing the seam. Why? First of all, their name might vary depending on where you live (see table above).
The second point, as we have already mentioned, is that that description will most likely be translated into the native language of the factory. So, we not only add another step to the process, but we also have another chance for confusion.

Photos are usually more effective that texts. The problem is that sometimes we don’t have the pictures we need. Or we only have the picture of the right face of the seam (so the information is incomplete). Then, the file will be heavier to send. And I am assuming the quality of the photo is good in terms of image definition.

And regarding the seam sketches, even though they are the most professional and specific type of resource, the biggest challenge I have seen is that the designer clearly understands its representation. But it is also true that after a short time using them, they not only interpret them quickly, but also prefer them for their practicality.

Explain the assembly of your garments properly.

In my experience, I have been using seam sketches for almost 20 years. I have worked with suppliers in the five continents, and have had excellent results. Even the factories respond to me with seam sketches to suggest changes.

Also, on many occasions I use the text to clarify the message (not to describe the seam). And pictures are very handy for those more complex seams that need to be visualized.

Conclusion and summary

The most effective way to explain garment assembly is the combination of these resources, especially for complex seams.
The combination of these 3 resources is an essential tool.

When the construction of a design is clearly explained from the beginning, you receive better-made prototypes. That allows you to focus your time and energy on improving the fit of the garment. And it helps shorten the development process, requiring even fewer samples to give the OK for production

Reference Material

tech drawings/templates in adobe illustrator 

Fashion Design Tech Pack Overview, YouTube video by Zoe Hong 

Garment Assembly: Why and How to Specify It / blogpost by Tech Packs.Co 

The Ultimate Guide to Tech Packs in Clothing/blogpost by White 2 Label Manufacturing 

– Carr, H., and Latham. Technology of Clothing Manufacture. Blackwell Science; 4th edition, 2008. ISBN: 978-1-405-16198-5

– ISO. Textile. Seam Types: Classification and Terminology. ISO 4916-1991. Genève: ISO, 1991.

– ABC Seams® Pty. Ltd. 101 Sewing Seams: The Most Used Seams by Fashion Designers, 2nd ed., ABC Seams® Pty. Ltd., 2021. ISBN 978-0-6482734-6-2.

– Glock, Ruth E. and Grace I. Kunz. Apparel Manufacturing: Sewn Product Analysis. Pearson, 2017.

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The Importance of Technical Development in Fashion Design
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ABC Seams

The new standards for inspiring, communicating and referring sewing seams.