CAD 101 part one

I’m pleased to present part one of a two part series on CAD -computer aided drafting/design written by two regular visitors to our site, Esther and Angela. By the way, if you have ideas for an article and want to write one, be sure to let me know.

Esther has worked as a designer of children’s clothing (sold in big box retail and specialty boutique stores), a technical designer, and a pattern maker for the last ten years. Her latest venture is TinyPackages an online retail boutique featuring baby gifts, clothing, and accessories. Esther continues to work as a contract pattern maker, part-time librarian and squeezes in regular updates to her blog Design Loft.

Angela has worked in the garment industry for 25 years, including pattern making, grading, and cutting for the bridal and junior markets. When her children were young, she started doing freelance pattern making and grading from home, expanding to the design of custom bridal attire including costumes for the film industry. She and her family manufacture made to order special occasion children’s clothing through their website Eve and Ellie.
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Computer technology has invaded nearly every aspect of our lives. Surprisingly, computer aided drafting for apparel has existed in one form or another since the 1970’s. It has only been recently that computer technology has become affordable for the average person. Many new design entrepreneurs look to computers to relieve some of the work required to develop a new style. Even though computers have become more affordable, pattern making and grading software is still a very expensive investment for a new company. In part one of this article, we will review basic terminology, discuss required skills, and basic costs. In part two, we will review the most common and well known drafting programs.


Before we can begin our discussion about CAD systems and small DEs, we need to define a few terms. CAD is an acronym for computer aided design. Strictly speaking, CAD refers to any type of design work created by using a computer. This could include graphic design, animation, digital photography, drafting, etc. In this article, we will use the term CAD to refer to 2-D or flat pattern making done on a computer. There is such a thing as 3-D modeling/draping on a computer, but for now we will focus on the basics.

The next key terms to define are hard patterns versus soft patterns. A hard pattern is made from a pencil and paper (or tag board). It is very tangible – meaning you can cut and slash a pattern directly with physical scissors or draw a line with a pencil. A soft pattern is a digital version of a hard pattern. Nearly everything you can do with a hard pattern can be done to a soft pattern. The difference is the media and tools that are used. To simplify our discussion we will refer to a soft pattern simply as a pattern and a paper pattern as a hard pattern.

Some other important terms:

  • Digitize – the process required to put a pattern into the computer from a hard pattern using a stylus and tablet.
  • Digitizer or Puck -a mouselike input device with buttons (to input grade rules) and cross hairs for exact placement in digitizing hard patterns into a CAD system.
  • Stylus – this is like a computer mouse but in the shape of a pen. Some pattern makers prefer this over a traditional mouse.
  • Tablet – a flat electronic board (used with a stylus, puck or digitizer) that allows for digitizing hard patterns into the system.
  • Plotter – a wide carriage printer. Plotters range in width of 24″, 36″, to 72″ wide. They hold a large roll of paper and stand on legs. These plotters have ink pens or wells to print and knives (certain models) to cut the pieces out.

Is a CAD system appropriate for a small DE?
This is not an easy question to answer. So much depends on individual skill levels, desire, and need. A CAD system may or may not make your business run more efficiently. If you can justify the cost, have the basic skills, and desire to do things yourself, then go for it.

Many manufacturers even today, do not have CAD systems themselves. This is not to say they don’t need or don’t use CAD. These manufacturers outsource this function to companies that provide CAD services, most notably for grading and marking. While the majority of companies may not have CAD systems, the majority do use CAD for grading and marking.

There are some features to consider when deciding whether a CAD system is right for your venture. Once you’ve become proficient with a system, CAD drafting is much faster than hand drawing. If you are a mid size to large company you can see the obvious benefit here. If you are a small, one or two person company the time saved with even a basic system can be allotted to your gazillion other duties. Mundane tasks like truing seams, naming pieces, and adding seam allowances are much faster, not to mention the speed and precision of computer grading. Once your grading libraries are developed (which takes very little time) applying grading to a pattern takes minutes instead of the hours it can take if done manually. Full systems allow you to adjust a graded and marked pattern with a few clicks on the base size; and have the changes update through all sizes and the marker—another major time saver.

You’ll see a decrease in the need for hard patterns (less storage space needed) and you’ll save time costing your garments with computerized layouts and quick spec exporting to spreadsheet software for tabulating yardages and components. For companies working with overseas contractors, file (pattern) transfers can be sent over the Internet in minutes at very low cost saving time and money on expedited delivery of hard patterns.

You can realize faster speed to market depending on the package you choose. Some systems offer full integration with every aspect of your production. This can include design, story boards, fabric and print design, pattern making, fitting with virtual fit models, grading, costing, marking, cutting, tracking through production, accounting, and more.

Required Skills
It is true that you will likely receive training from whomever you purchase your system. The training does not include pattern making, grading or pattern making skills, except at a basic level. The training will help you set up your system to work most efficiently with your goals and product. You will likely receive an overview of the tools and how to use them. You must already possess basic pattern making skills to make the most use of a CAD system. Even though some CAD packages will draft patterns for you (through made-to-measure modules), you still need to fine tune and clean-up the patterns manually. Here is a simple break down of skills you should already possess:

  1. Pattern making and draping by hand. You must already know how to make patterns.
  2. Familiarity with grading and marker making.
  3. Computer literacy. You should know how to use a computer and do basic troubleshooting (or know someone who can). Most CAD providers have technical support, but it is at an additional cost. Also, protect your computer with the usual virus and spy ware protection software packages.
  4. Enjoy using a computer for long periods of time. CAD programs have made pattern making more efficient and easier, but it still takes time and patience.
  5. Sew. You have to plot out your patterns and test them in fabric.
  6. Attention to detail.
  7. Basic math skills.

General description of software packages.
A basic package consists of pattern drafting, grading and some marker capabilities. Training varies per company. Most will have you purchase training that includes initial on-your-site training for you or your pattern maker and maybe a yearly technical support contract. Some companies also offer CDs and/or on-line training. As your budget and needs allow, you can add features like advanced marker capabilities, 3D designing, made-to-measure, product data management, and textile design modules. Each of these modules can increase your work efficiency in various ways. Here is a brief description of optional modules available for additional cost.

3D design visualization modules allows the designer to preview a design on a virtual model to check fit, design and fabric behavior. Some systems will calibrate your virtual model with the identical shape and specs of your live fit model through the use of body scanning technology. 3D samples cut down the approval process of a design and save time and material allowing you to view a garment without cutting and sewing first. You can create libraries of scanned fabric swatches for your designs that can be applied to your 3D model so you can “sew up” a garment in the actual fabric. Prints and patterns can be scaled to reflect their actual size in a given garment. Some systems allow you to add animation to your model so that you can see the garment in action. Animated models accurately portray the garment in its intended use; you can observe points of stress, poor fit or unappealing style line placement, and make these primary corrections before the final test in fabric. Advanced systems simulate the actual fabric of the garment, from the softest chiffon to leather and denim. Another advantage of the 3D model is the ability to send snapshots or videos of the design to other members of the design/approval process, quickly over the Internet for immediate feedback.

Made to Measure functions work for both mass customization, like Lands End which offers on-line custom sized clothing, or for a smaller custom clothier. A bridal designer, for example, may offer custom sizing of static seasonal designs for a size varied clientele.

Product data management (PDM) software offers sophisticated tracking/planning systems for all stages of production with the ability to evaluate each operator’s efficiency and quality of work. The computerized work flow increases productivity and automates many labour/skill intensive functions systematically such as; generating work/cutting tickets, pre-planning of resources and line-allocation. PDM systems can store all necessary data for each style in one location, which can be disseminated to various contractors efficiently.

Some systems offer fabric related modules that allow you to design fabrics such as plaids, special weaves, knits and Jacquards. Print design modules for designing printed designs and patterns for your unique look. Some systems offer drawing features for producing story boards and catalogs with realistic texturing of fabrics. Some of these tasks can also be accomplished with graphic design software such as Photoshop and Adobe Illustrator.

Packages designed for mid to large sized companies with in-house cutting facilities will include plotting and cutting abilities for manual or fully automated environments.

Workspace Requirements
You will need a dedicated work space for a CAD system. The amount of space actually required will vary on your system set-up. A basic system will require a desktop computer with the usual peripherals – printer, mouse (or stylus), and speakers. A 19″ monitor is ideal, although you can use smaller. Most systems can be installed on any computer and operating system – you won’t necessarily need the latest or greatest computer. I used one CAD system installed on an inexpensive eMachine available from Wal-Mart. Some CAD providers will try to sell you a computer for thousands of dollars, but in reality those computers are not much different from inexpensive models available from other suppliers.

Your computer should be set-up close to a drafting table. Even though you will do most of your drafting on the computer, you will still need the space to accomplish many tasks. This includes digitizing a pattern, verifying pattern plots, checking measurements against a hard pattern, and many other uses. Many CAD systems have optional drafting tables, but feel free to shop around. Some systems can be configured around a drafting table instead of a traditional desk. The computer tower sits underneath and the monitor floats above the drafting table.

If you do not use a printing/plotting service, you will need space for a plotter and/or cutting machine. The most common plotter (a stand up plotter) does not take up much space and they are relatively inexpensive. Some plotters are equipped with a knife blade that will cut out your paper patterns for you. Another option is to cut sewing samples (in fabric) directly from your CAD system on a small cutting machine, a huge time saver. A cutting machine is an extremely expensive piece of equipment, so many DEs will not be able to purchase this right away.

A CAD system is most efficiently set-up near the same area where samples are sewn. This will allow a pattern maker to work closely with sample sewers and make quick modifications to a pattern.

The most important piece of your CAD system is a dongle or hardware key. This is a small device that is placed on the back of a computer onto a parallel port. A dongle unlocks your CAD system and allows you to use it. It would be a good idea to insure this piece of hardware, you will be stuck without it. A replacement dongle is the price of a new system. Only authorized individuals should be allowed to touch it. Don’t make the mistake of buying a used CAD system unless it includes the dongle. Without the dongle, the program cannot be used.

In part two, we will discuss the attributes of various CAD programs on the market today.

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12 comments

  1. Eric H says:

    Erg – the dongle, bane of my existence. I suggest that you tag it with your contact information and a large label that says “Remove and return to me” before you do anything else. If you ever move your office around, or change computers as you upgrade, etc., it’s easy to forget the dongle because it’s behind the computer. A note like this will prevent it from being thrown away by someone not familiar with it. The newer dongles are USB-based rather than parallel port, so it’s easier to put them into a USB hub that sits on your desk in plain sight.

    I would also like to say that a great benefit to putting your documentation into CAD is that you can keep old designs around at very little cost for years. When someone comes around 10 years later and asks, you can call it up almost immediately. This brings up two issues:

    1) Archiving. You are backing your valuable computer files up regularly, aren’t you? How are you storing them? What happens, for example, if a fire destroys your work area? You should consider archiving your backups from time to time and storing them somewhere separate, like a safety deposit box. For big operations, there are professional services that do this – services that got much more popular after 9/11 (think of all of those financial records that might have been lost if they hadn’t been duplicated at an off-site storage area!).

    2) Naming conventions. You should figure out how to name your files in a rigorous manner, similar to style numbers (you are numbering styles, right?). Perhaps you include the style number and date of final revision in the file name (remember that the file date is sometimes changed when you move or copy it, so don’t depend on that). The naming conventions should make it easy to search for a particular file years down the road, so try to build a robust standard.

  2. Esther says:

    You are right on about making data back-ups. Very important!

    All of my pattern names are based off of the style number. That way I can see how a pattern has evolved from the base over time. Kathleen has blogged about pattern naming/numbering systems in the past. And that system can certainly be applied in CAD programs. Perhaps I will blog about it later on my blog. TukaTech has an info box for each pattern. I make a note when I modify any pattern and date it.

  3. Great Article. I am in the process of studying “The Entrepreneur’s Guide to Sewn Product Manufacturing” which I should have done first. Unfortunately, I didn’t, and as a result I lost $600 unnecessarily plus spent another $1000 too early, and this money too may be wasted.
    In any event, no one said an education was cheap. I can really see the value in CAD because of the points discussed in “The World is Flat” by Thomas Friedman.
    I have rejected the 3 pattern makers I found in the Miami area because they do only hard patterns, just like Tama Mfg.
    I believe that CAD pattern makers will have blocks to start from especially in the sports apparel industry which is where my expertise lies.
    I have learned that all properly designed bicycle windbreaker/rainjackets come with a basic design that allows the jacket to cover the buttocks when the rider is bent over at the waist with arms extended forward. There are hundreds of different types of these jackets made. I as the DE for my cycling jacket have to maximize the use of the most suitable fasteners, fabric and color to set my jacket apart.
    Therefore, there is no reason to re-invent the cycling jacket, anymore than to re-invent the sock.
    I need a CAD pattern maker with a library. Just as auto mechanics have a library on CD’s so that they can communicate with any car’s computer (even though she might only work on Chevy’s and Honda’s, I expect my CAD pattern maker to have a library of patterns on CDs. Therefore, when he starts doing a pattern for my cycling jacket from my sketch, explanation and prototype (my wife I made), he starts with a cycling jacket, and not with a blank screen.

  4. Kathleen says:

    gee Gary, not to be quarrelsome or anything but I only do hard patterns, no CAD. The reality is, very few manufacturers have cad systems (15%). Of the ones that do have cad, 85% only use the system for grading and marking. There are those of us who stubbornly insist that we can make patterns better and faster by hand…that’s a standing challenge btw. Not for simple blocky things, but complex stuff.

    Btw, having a library of blocks is not restricted to those with a cad system. I have plenty although not of your product type. Now, if you wanted men’s suits, sportcoats, ladies outerwear and leather coats, that’d be another story altogether.

    Lastly, while I do have patterns on hand, many of them belong to a previous customer so ethically, I couldn’t use them for another customer. Having patterns and being able to use them are two different things. Sure, cad systems have loads of templates but personally, I’ve never been happy with them. The fit is off, construction needs reworking, they still need personalization to a given client.

  5. Esther says:

    Gary,
    Just wanted to echo some of what Kathleen said. I may have a library of patterns to work from and a bicycle jacket may be a basic design, but that doesn’t mean you will get what you want easily. I pull from my basic patterns and modify them to meet the specifications (measurements and design) of the client. Just because a jacket works for someone else, doesn’t mean it will work for you. There are endless details of minutia that have to be worked out. The end result will be far removed from the library block and made specially for you.

    I am opposite from Kathleen. I probably do 85% of my patternmaking by computer. Once your basic blocks are digitized, it is rather easy. Basic blocks are almost always drafted and perfected by hand and then digitized. I have drafted patterns from scratch in the computer, but it actually does take longer.

  6. jocole says:

    wow, this was amazing, i cannot wait for part 2, as it is right now i’m still working off of my hard patterns and grading by hand (but i actually enjoy that part of the work) but when i grow i will definately be looking into CAD

  7. Angela says:

    I also do the majority of pattern/style changes on the computer working from blocks that have been digitized in, or a previously made style that is similar. For designs that require a new block, I develop them by hand and once they’ve been sampled and corrected, digitize them in. One reason it is faster and less costly to establish your blocks and really complex patterns by hand is; for every iteration or tweaking of the pattern, you’ll need to plot it out to test it. Unless your hard pattern is way off the mark, you usually won’t have to make/trace a completely new pattern for each sample you test.

    I also find it easier to “see” the pattern when working by hand. Since this is the way I learned how to draft, my eye has been trained to recognize how lines/shapes should look for a given style, and I can easily adjust and re-draw things that don’t “look” right.

  8. jme says:

    i look forward to the review of the diff programs offered. it is not an easy thing to get into as a de because of the expense but thank goodness for the rental programs…hopefully you will be able to spell out what is out there tit for tat…

  9. colleen says:

    Thanks for the interesting article. I hope you’ll include ball park costs for the CAD systems in part two and examples of best “return on investment” for DE’s.

  10. Trish says:

    Kathleen, if you would like to use the CAD system at El Paso Community College, just let me know. We might even be able to find some students who are willing to digitize the patterns.

    We are still using MicroMark, which is a great program… too bad GGT didn’t keep it alive after they bought out the competition, but there you have it! The best product does not always outlive the dinosaurs.

    Talk to you soon!

  11. Pattern makers (PMs) have limited knowledge of clothing used for cycling, but they all have seen the team clothing of baseball players. If I wanted to sell summer baseball uniforms, I would want my pattern maker (PM) starting with a medium pattern for what is in general use today by baseball teams during simmer months.
    With that as a starting point, I can select the parts of the pattern to be in the various materials and colors which will set my uniforms apart from what’s out there now.
    The similarities of the pattern of the multitude of windbreaker jackets used in road cycling are just like the similarities of the pattern of the hundreds of summer baseball uniforms being used.
    The use of soft patterns optimizes communication between the DE and the pattern maker(PM). The DE emails, PM replies. Neither interrupts the other and the emails provide a complete history of how the pattern is arrived at.
    Once the pattern is established, I email it to a seamstress in China or Taiwan or here in the USA where it’s sewn into a sample and air mailed to me.
    Using email, I can send the pattern out for bids to several contractors for bids.
    The fabric suppliers can be kept fully informed of the use of their fabrics by email.
    Using the foregoing system, I can compete with Nike.
    These ideas that I express here are implementations of those cocepts presented by Thomas Friedman in “The World is Flat” and Kathleen Fasanella in “The Entrepreneur’s Guide to the Sewn Product Manufacturing”.

  12. Daria Karaseva says:

    Maybe a little bit unexpected question…
    Is there a website where I can download this 3D CAD programm? Or I have to go to the store for that software?

    Thank you,
    DAria.

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