CAD vs CAD

Posted by Kathleen Fasanella on Dec 1, 2008 at 4:08 pm / Designers must know, Patterns / Trackback

Let me preface this entry by saying that no one I’m working with should feel this is directed at them. It’s not. Really. This is an ongoing source of confusion that seems to be rampant lately in other forums and those of you who have participated in those other communities know exactly what I’m talking about.

So let’s get to the heart of it, what is CAD?

  • CAD is Computer Aided Design
  • CAD is Computer Aided Drafting

At least in our industry, these are not the same thing and while I can’t say they are never interchangeable because I can’t know all import specs on every CAD drafting program, let’s just say they rarely are. The problem is that many people think CAD design and CAD drafting are interchangeable and this gives rise to a whole host of communication problems and excessive costs that could have been avoided. Even Mr. Fashion-Incubator (an electrical engineer) complains about Illustrator files he gets that are claimed to be drafted blueprints.

  • CAD Design is done with programs like Illustrator. There’s some other ones too.
  • CAD Drafting is done with programs like Gerber, Lectra, and StyleCAD.

Now, I will not deny that there are people who can draft in Illustrator, I’m sure there are. The issue is, how useful is it? Does this represent the best expenditure of your dollars? I would say probably not. The reason is your pattern -in effect, an illustration- can’t be exported into a computer aided drafting program for the purposes of grading and making markers. So like it or not, you will have to have the work redone in a drafting program.

Here’s two examples of what I mean of an illustrated pattern from someone who used Illustrator.

Okay, I realize some of you are falling over yourselves laughing but you would not believe how many “patterns” I have gotten that are just like this. The client assures me over and over that the pattern is ready to go and just needs to be made into a marker. The person who hired the job out considers them to be patterns (I’m guessing) because the illustration is full scale and according to specified dimensions that are usually labeled neatly off to one side. That’s really nice and it’s not that these aren’t useful, but these are technical illustrations, not blueprints. I don’t know of a miracle worker on the planet who can pull in one of these “patterns” and make a marker from it. Besides, if your CAD designer is using Illustrator to draft, that should raise several red flags right there. First it is very likely they are not specialized in the apparel industry because they’d know our marker making software won’t talk to these files so they wouldn’t be using Illustrator to begin with. If they don’t know enough to know Illustrator won’t work, how will they know the seam allowances or construction? Is your designer/drafter an expert seamstress? As I’ve said ad nauseum, patterns are tools. How can one design tools unless they know how to use them?

There was one really infuriating example with this guy who wanted his patterns graded in Illustrator because that’s the program he uses to render the artwork designs (tee shirts of course). Nothing we said held any sway. You can’t grade in Illustrator. The only way you can grad in Illustrator is to give it an “F”. Regardless of whether he’s found someone to do it, there is no doubt he’ll need to hire someone else with a CAD drafting program to do it all over again. And sure, you’re the boss but boss or not, it doesn’t mean we can work in your preferred software program. Unfortunately, you’ll have to bend on this one.

From a production standpoint, below is the most basic rendering of what a pattern looks like.

I’ve gotten patterns similar to this too. But again, because the designer is not an authority in the apparel industry, they don’t know this is nowhere near what we need. I realize this may sound trivial and nit picky but we need to know several things such as fabrication, piece names, size and how many of each piece to cut. As such, we’re more accustomed to something like this below.

Now this still isn’t enough, sad but true. Your illustrator may have spec’ed out your product to scale but they didn’t know about all the internals that go into making the product; this is a function of computer aided drafting, not design. A complete pattern will look more like this (below).

This still isn’t enough to make a marker from. Minimally, you will also need a direction card, aka face card, aka pattern card (page 79 of my book). Making this is the responsibility of whoever makes the pattern. Actually for a marker you really need a cutter’s must but anyone could get the needed information off of a properly made pattern card. To have a marker made, you will also need to design a cut order plan. This can be found on pages 116-118 of my book (see “marker planning”) but more broadly, that whole section spanning pgs 114-120 is pertinent. It seems many designers skip that section being production related and technical but really, you can absorb enough of the material to get the desired result from a service provider.

What many also don’t realize is that they need more than one marker made. The example I’ve shown here actually needs three. One for shell,

another for lining (left) and another for interfacing (right)

because these are the material groupings of all the inputs that go into it. The problem with many of the (pretty) Illustrator files I’ve seen are that pattern pieces representing different materials are laid on top of one another (like a technical sketch) rather than separating them out by pieces.

In the end, illustrators are great at making pretty and tidy illustrations, but these do not patterns make. Better to know that now than to find out with your back up against a wall with a production deadline.

Now, if it is true that your illustrator has spec’ed the design out properly to scale, your best option is to have it printed out and sent off for digitizing. Contrary to prices I’ve seen around, this isn’t an expensive job. I don’t know what other people charge but my son does it for me part time and I bill it out at a rate of $25 an hour. A design like this, such that I’ve shown here with 20 pieces would take an hour and a half at most. I would think the highest hourly rate you could expect to pay would be $50-$75 an hour. This is because some pattern makers don’t have an assistant or intern and have to charge their regular pattern making rate.

16 Responses to “CAD vs CAD”

Comments RSS feed

Lisa DOWNTOWN JOEY
December 1st, 2008
6:28 PM

Great post!!!

Rocio
December 1st, 2008
8:07 PM

This couldn’t have come at a better time…
I love how you explained the difference and feel better to know that I’m not alone in getting patterns that are NOT READY to be graded or used for a marker.

Mary Lombard
December 2nd, 2008
10:35 AM

Wow, I had no idea that people actually considered Illustrator drawings patterns. Yikes! And I thought I had it rough telling people in China how to make patterns…

aimee
December 2nd, 2008
2:39 PM

just in skimming this article, i completely understand the dilemma and agree with you. i suppose unless you have credible work experience/knowledge behind you, perhaps you might not know the difference. i work for a full service apparel company. we do everything: from concept to design, to CAD (as in to show to buyers and also for tech paks), we do the specs, the labels and hangtags, right down to the bar codes and anything that has to do with delivery. we do not grade anything UNLESS we perform formulas in an excel worksheet (to go with the said technical sketch in illustrator). perhaps the best advice for people NOT using gerber or lectra, etc. is to have them learn their formulas in excel. it’s a wonderful tool that factories understand. and simply put, illustrator is great for many things, but certainly not marker making or grading.

Eric H
December 2nd, 2008
11:04 PM

To be clear, the problem is usually not mine. The problem is usually my mechanical engineer, who sometimes gets PDF files in place of DWG (AutoCAD) files. Metal parts are 3-dimensional, and as luck would have it, we sometimes want to bolt them to other parts that weren’t made to fit and so something has to get modified. People invariably leave critical dimensions off their paper and PDF drawings. The difference is that he can pull dimensions (**exact** dimensions) off the DWG files.

Patterns are engineering tools, not fashion illustrations.

Trish
December 3rd, 2008
4:22 PM

I really have to make sure my students read this entry, just so they can see you talking about the way we have to view everything. Sometimes I think they feel that I am making this up!

Kerryn
December 7th, 2008
2:29 PM

Wow, like Mary above I’m dumbfounded that people would even consider creating patterns in AI! However, I use AI regularly for flats and construction illustrations, and I import files from my CAD system to create print and embroidery schematics or illustrate pattern amendments to other Patternmakers.

Francis
January 6th, 2010
2:23 PM

Before Gerber and Lectra there was manual pattern drafting. A pattern is only as good as it’s pattern drafter. The program is only there to supplement that knowledge base. If one knows the proper rules of pattern drafting it could be argued that even a program like illustrator could be used to draft and in fact is more accurate than manual pattern drafting. It must of course be understood that the files are incompatible with current drafting software and would have to be digitized for computerized grading and marker making. That being said manual pattern drafting does as well and there are lots of small start ups who do it the old fashioned way with paper and pencil. Not everyone can afford to draft on a cad system. Just wanted to argue the flip side of the coin.

Kathleen
January 6th, 2010
4:14 PM

Your points are well taken Francis. I believe I said as much in my entry:

Now, I will not deny that there are people who can draft in Illustrator, I’m sure there are. The issue is, how useful is it? Does this represent the best expenditure of your dollars? I would say probably not. The reason is your pattern -in effect, an illustration- can’t be exported into a computer aided drafting program for the purposes of grading and making markers. So like it or not, you will have to have the work redone in a drafting program…. Now, if it is true that your illustrator has spec’ed the design out properly to scale, your best option is to have it printed out and sent off for digitizing.

The inspiration for this particular entry was an individual who wanted a marker made from her Illustrator generated pattern. Impossible. She hired someone who claimed expertise they did not have. They had all the pieces nested inside each other, no seam allowances etc. My central point is, if your pattern maker isn’t using a medium that can be used by others farther downstream in the process, they likely aren’t the whiz bang authority they’ve convinced you they are.

Sara
March 2nd, 2011
12:10 AM

Though this is a thought provoking argument and I agree that the expensive programs used for industrial pattern design are awesome….they are just not accessible for everyone who loves patterning and digs on designing patterns based off of the human form. I love Illustrator for pattern making! It is a completely viable and reasonable program to make patterns with…you just have to have faith in your skills a draftsman and capabilities as a measurer and grid layer of the human form. I think it would be a profound skill if every fashion student had to learn how to draft a garment pattern in basic vector programs. Talk about changing the current climate of the industry! People are amazing and so are their capabilities to use these currently thought of as ‘amateur’ programs to make their designs come to life. Where there’s a will, there’s a way and I believe in the power of bringing pattern production to accessible programs. Much love to all those who love fashion and drafting :)

Kathleen Fasanella
March 2nd, 2011
9:00 AM

It is a completely viable and reasonable program to make patterns with

As I mentioned in my comment,

The inspiration for this particular entry was an individual who wanted a marker made from her Illustrator generated pattern. Impossible… My central point is, if your pattern maker isn’t using a medium that can be used by others farther downstream in the process…

Please keep context in mind. The debate in this entry was not whether Illustrator is an option for someone doing a one-off with more time than money; it was a commercial party hiring a service provider who was using non-standard tools to generate a product that failed to encompass necessary elements (seam allowance for one) that could not then be used by service providers downstream in the process. See CAD software compatibility in marker making which explains why.

The biggest problem with using Illustrator is that it can’t be used after that point which for most of us, is the whole point of having digital patterns. See:
How to know if you need digital or paper patterns

celeste
December 4th, 2011
9:03 AM

I don’t know why, but I had never considered Illustrator to be a CAD program, but I think that has more to do locally at the CC, that (auto)CAD is the drafting part and Illustrator classess was the graphics part of the dept. But I can see how CAD and CAD can become very confusing.

I do know people that draft in Illustrator, but their patterns aren’t used for commercial production. I can see how it totally wouldn’t work for that.
I think more people are trying to use design software for drafting becuase the software is more acessible. (especially price wise)

At least as long as I read your blog I’ll be well informed even if I’ll never get to apply it.

[...] resist learning CAD 3D pattern CAD software CAD: PAD or TukaTech? (I ended up buying StyleCAD) CAD vs CAD addthis_pub = [...]

Daljeet Kaur
May 5th, 2012
6:17 AM

This is a test I did recently:

I made a draft in Illustrator (4 piece full-sized pattern). Then I exported it as a DXF (to my desktop). Then I opened my CAD programme and imported the DXF into it. It opened with all the dimensions intact. I could grade it and make a marker out of it in the relevant CAD programmes.

Chez
October 24th, 2012
9:20 AM

I mainly deal with the concept side of fashion design, so providing the garment illustrations as Illustrator files but not as pattern-ready files. I was wondering though, if I provide these to a client as AI format, are they able to open these files in Lectra as reference to work a pattern up from or to develop in Kaledo as illustrations? Forgive me if I sound ignorant, I’m not familiar with the drafting programs such as Lectra.

Thanks for any input anyone has on this!

Christopher Jay
February 18th, 2014
11:31 PM

This was a great start for me; someone who has read Kathleen’s book but who is a true neophyte.
I make blankets and pillows which are far simpler but. Require a lot of similar thought but less parts compared to most clothing.
BTW, I LOVE THE FORUM and I am amazed at the quality of the members.

Leave a Reply

Current day month ye@r *

Archives

Categories

The Entrepreneur's Guide to Sewn Product Manufacturing

Often described as the garment industry “blue book”, the most highly rated book in the business is guaranteed to get you off to a solid start or your money back. Many service providers require you read this before they’ll work with you. Learn more »

Subscription Options

RSS Feed Google Reader My Yahoo My MSN Technorati

Subscribe by email: