CAD vs. Engineering
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Episode Show Notes
Step into the classroom of 16-year veteran CAD teacher Audrea Moyers. Audrea also teaches engineering design, and she talks about how the pathway of CAD and engineering classes at her school link up. What are her thoughts on the different CAD packages out there? How do you integrate more design into a CAD class, and vice-versa? Where do you teach drawing by hand? Hear about all this and more in this conversation.
Remember that the podcast will be at the SXSW Conference and Festival in March, 2017! Pius and Rachel from the podcast will be running workshops for educators and professional engineers: www.sxsw.com and sxswedu.com
Our opening music comes from "School Zone (radio edit)" by The Honorable Sleaze. Our closing music is from "Late for School" by Bleeptor. Both are used under Creative Commons Attribution Licenses: http://creativecommons.org/licenses/by/4.0
Subscribe and leave episode reviews wherever you get your podcasts. Support Pios Labs with regular donations on Patreon or by buying a copy of the reference book Engineer's Guide to Improv and Art Games by Pius Wong. You'll also be supporting educational tools and projects like Chordinates! or The Calculator Gator. Thanks to our donors and listeners for making the show possible. The K12 Engineering Education Podcast is a production of Pios Labs.
The K12 Engineering Education Podcast
CAD vs. Engineering
[Pius Wong] This is The K12 Engineering Education Podcast for December 6, 2016.
[Pius] The other day, I visited the classroom of Audrea, a high school engineering teacher here in Austin who has many years of experience teaching computer-aided drafting, or CAD, along with manual drafting. You might know that drafting is the skill of representing physical designs in technical drawings, and it’s closely related to engineering. I spoke to Audrea in her classroom about what she’s learned teaching CAD and engineering to kids.
[Audrea] My name is Audrea Moyers, and I teach engineering. I teach a pathway of engineering courses at McCallum High School, and that includes a couple courses that focus pretty heavily on engineering drawing. So that would include both 2D and 3D CAD.
[Pius] All on the computer?
[Audrea] So we do – In the third level class, it’s called Advanced Engineering Design and Presentation. We do about four weeks of manual drafting, which I do because my classes articulate to Austin Community College, and they have an advisory board, and their advisory board has professionals that say you still sometimes need to be able to manually draft. Maybe drawings have been submitted to the city, and you can’t take the drawings out, and you need to make a change. You actually make a change on the scale drawing. So they say it’s still a skill, so they do it in their courses. So I do it, and I don’t do it at the beginning of my first CAD class, because one year I did that, the kids dropped like flies, because I’m making them do, you know, very old-school, T-square, triangle drafting. And that was only a piece of the class. It’s a small piece, but when I did it at the beginning, kids were not happy with that. And so I now tuck it into the curriculum a little bit latter. They’ve already kind of committed. They’ve done a whole year, really, of CAD, before I say, hey, let’s learn how to do some of this stuff by hand.
[Audrea] It’s hard because there are just some really basic neatness issues with it, not just like – the geometry. The conceptual hardness is not really any harder than CAD, but just line quality, learning how to draw a neat, straight line, and sharp, dark corners, and using the compass. I mean, a lot of the kids are just struggling with the tools. A lot of it’s just drawing enough that the tools are not an impediment to getting the drawing down. And so that’s the real hurdle with the manual drafting, is the tool use.
[Pius] So they have to learn a little bit of patience or something.
[Audrea] They do. And some kids love it, and other kids can’t stand it. They’re like, when are we going back to CAD? But I see a definite progression in all of them. Their drawings are neater, and their line quality is better by the time they’re done. Some of it’s just practice.
[Pius] And how long again, how many years have you been teaching CAD?
[Audrea] I’ve been teaching CAD for sixteen years. So of all the courses I’ve taught, that’s the most consistent. Most of my courses have kind of evolved over time, from kind of just an introductory technology credit, to full-on engineering design, but I’ve had a CAD class more or less unchanged for about sixteen years.
[Pius] So you know what you’re doing.
[Audrea] And the software, you know, keep updating, but the concepts have not changed. I mean, AutoCAD as a program is pretty much like it was thirty years ago when I used it. It’s just got a lot more bells and whistles to make drawing easier, but the concepts are pretty much the same. I guess the big change is 3D modeling. The programs like SolidWorks and Inventor didn’t even exist when I started teaching CAD.
[Pius] So what software do you use in your classes, and why?
[Audrea] I’ve been teaching AutoCAD the whole time, and so partly that’s because I think it’s kind of the industry standard. So if you’re going to learn one CAD program, I think that AutoCAD is a really good one to learn. And you can quickly learn other programs from that. Also because of articulation agreements, and so my courses do articulate to courses at Austin Community College, and they use AutoCAD. So as long as kids can get some college credit here at the high school level, then I’ll be using the same software. So that’s the 2D program. For 3D, I’ve used a couple different programs over the years. I started with SolidWorks. We got a grant for that for a few years, but eventually that grant money was done. We were several versions behind, and so Autodesk had a package where you could get like the design suite. So I was using Inventor at that point for 3D modeling. And now of course, Autodesk has made everything free for education, and so that’s definitely a reason to use it, because my students can use it at home if they want to. Not many need to. A few choose to do it. But they have that option, that they can continue to use this program in college. So I think it’s a versatile one that they can take with them after they leave.
[Pius] So then if a lot of companies like Autodesk, they have this software for free, other companies have it at low cost for education, is there any reason to use a package like Sketchup or something that’s a little less powerful?
[Audrea] I actually do use Sketchup also. I do use SKetchup for the architectural work. So I do both architectural design and drafting, and Sketchup is designed for architecture. It works very well as a, just jump in and start using it. It’s super easy to use, but it’s not as powerful, and so it’s a great kind of early design tool, and I use it in both my introductory class, which is mostly freshman. We do a really small architectural project, like a specialized room, and they can – After they’ve done their 2D design, like a floor plan, then they can do the 3D, the height and the roof, and everything else, in Sketchup pretty easily. The pro version even lets you take your floor plan and bring it right in and make it 3D. With the older version, the free version – I think they call it Make now – we had to redraw the room outline to make it 3D. And that pro version does cost, but again there is that grant from a teacher group that allows you get it for no cost or low cost.
[Pius] So we know that you teach both CAD and engineering and manual drafting, from your perspective as a teacher, what’s the difference between these courses?
[Audrea] Well I’ll say first, for me, teaching CAD has two components. One is the software. So the tools of just the program. But the other big component is the theory of technical drawing, and so you can’t really separate teaching CAD from teaching how to we draw designs. And so the course does – The CAD course does tend to focus first on just learning the software, but really the majority of it is the theory of, how do we take a three-dimensional design and draw it in two dimensions? And we do get increasingly sophisticated with the software, but a lot of the real thinking and the real challenge is in the theory part of it. And so to me, the way my pathway works is my introductory class has a CAD unit in it, because it’s just a really useful tool, so we learn it early, so that throughout the year, if we want to draw something precisely, we have the tool now to draw precisely. But most of the work we do in that class is more conceptual design stuff. And then the next two classes do focus heavily on, how do you draw designs? And how do you learn the rules of drafting? It’s an international language to share mechanical design or a circuit diagram or an architectural drawing with someone in another country or in another city, right, when you’re not physically present. And then my final class is the UTeachEngineering Engineer Your World curriculum, which doesn’t have, really, any kind of CAD component to it, but when students have taken the other classes, then I think they have an advantage, that they have a tool to help them draw a design accurately. I feel like one of the – at the most basic level, teaching CAD gives them a tool to draw accurately, so they might have experience with other drawing programs or other types of drawing from art. They might have learned how to draw perspective drawings. They might know Photoshop or Illustrator. But they usually haven’t had a program when I get them that gives them precision, that gives them tools to be precise about drawing. And so if they were going to try to represent a design, if they went to one of those other programs, they would find it very hard to be precise. They have tools to make cool filters and things like that, but not tools to be exact. So a lot of what it does is it gives you a set of geometry tools that are exact, and once they know how to use it as just software, then they can start incorporating it into design projects. So they can either – Now AutoCAD is not particularly useful in the early stages of design. It is really meant to be final documentation, right? The first thing AutoCAD wants when you draw a line is, how long is the line? And if you’re still thinking what shape things should be, that’s not what you need. AutoCAD itself is not a design tool. But other programs, like SolidWorks and Inventor and Sketchup, they do have a way that you can be a little bit looser. And you can make some decisions that you can then change your mind on later.
[Pius] Parametric modeling and all that.
[Audrea] Exactly. Parametric modeling – AutoCAD is moving that direction, but it’s not that direction yet. So a lot of it depends on which CAD program you’re using, but – and that’s really, I think, where AutoCAD can benefit the engineering curriculum. It’s a tool to represent your final design. And so in that final course where they’re doing, like, right now they’re doing a pinhole camera design. Those students who’ve had a CAD class can very quickly and very accurately convey their design using a variety of technique. They could make an isometric drawing of it. They could make a 3D model of it. They could make an orthographic projection with top, front, and right views. And they would be able to do it using industry standard techniques, like hidden lines and center lines and things like that. So they just have, basically, an advantage on sharing their ideas with others.
[Pius] Like for their final report.
[Audrea] For their final report, their able to convey really precise what their design is. Students who haven’t had CAD can still make those drawings, but they’re usually not as detailed, and much more time-consuming, because they haven’t had the chance to learn those drawing tools.
[Audrea] I also try to put some design into the CAD classes. It’s not easy. There’s just a lot of curriculum that’s just learning the drawing, but it is best if they can draw their own designs and not draw someone else’s designs, and so I’m most able to do that with the architectural unit and when we do 3D modeling, so they have a project where they’re not modeling just some shape I give them. But they have a client, and they’re trying to design some sort of little project for a client, and they’re modeling their own design. And there’s a big difference in modeling your own design that you’re still thinking about in your head and just recreating shapes that somebody gives you, and so there’s a huge leap there. So I try as much to put some design into the CAD courses as well.
[Pius] That was going to be my next question, how you might incorporate design in to your CAD classes, because I would think that your CAD classes are really full, as well. I mean how can you do that and still have your kids take something away from that?
[Audrea] It’s mostly in the Spring semester. In the Fall semester, we’re trying to get the basics done, and that’s when we get a lot of our curriculum that articulates to the community college. We kind of really get very, very good at CAD. We do mostly other people’s drawings. We’re drawing, you know, very mechanical parts that have to fit together, and we’re learning section views and all the rules of drawing. And then in the spring, I have a little bit more time, and we do a 3D modeling project that really doesn’t articulate to ACC. This is really an addition where they do have their own project to do. So after they learn the basics of Inventor, then they get to model something that is original, and that’s where the 3D printer comes in, where they can actually print it. And that abstract shape on the screen isn’t the right size. Does it fit the part it’s supposed to fit? That’s where the rubber meets the road on the design, you know.
[Pius] Are they interested in that? Are the kids that take the CAD classes really interested in design?
[Audrea] They are. I think that they get tired of just drawing other people’s things, which, I have to say, we’ve got to learn the rules for this, but we’ve got to apply it to something else. My third class, which is the advanced CAD, I don’t do all the ACC curriculum, because if I did, we’d spend the whole year drawing other people’s designs. I think the kids need to be able to apply their own ideas and then figure out: how do I draw this idea I have in my head? How do I actually represent that in two dimensions? And so, like I said, I can do that a little bit more with the architecture projects, too.
[Pius] That’s interesting you put it that way. It sounds like your engineering class gets the idea in the first place, and your CAD classes help you bring that idea into paper or reality.
[Audrea] Yes. And I think that there’s – So we don’t have as much time in the CAD class to talk about things like ideation, how do you come up with good ideas, how do you choose a good idea. So we can talk about those, but we don’t spend as much time learning those techniques. We spend more time learning the representation techniques. You know that more complete design course for engineering cares a lot more about the design process. I mean I start talking about the design process in their freshman year, probably at the end of the first week, so I talk about it a lot, but it’s harder to demonstrate it until you get to those big design projects.
[Pius] You had mentioned that sometimes it’s a challenge retaining your kids in the CAD classes. Do you have the same challenge in the engineering classes? And if so, what are other ways you can overcome that?
[Audrea] You mean retaining like year to year? Is that what you mean? I’m not sure.
[Pius] Or getting – like the people who went into your CAD class at first, if you started with manual drawing they just dropped out. I guess my bigger question is: what types of kids go to these classes, and how do you keep them there?
[Audrea] OK. Well, it’s interesting. I’ve seen a big shift. The state of Texas has moved to endorsements for graduation, and so there’s now a STEM or engineering endorsement. So what I find is, I’ve been able to keep kids through the entire four-year pathway in the last few years. But before I could get them to take maybe the first two, and then around their junior year they have a lot of other things they want to take. Maybe they wouldn’t take the third class. I’d get some that would do a year or two, but maybe not the full pathway. I think there’s a little more incentive now to maybe complete a whole pathway. So I’ve got for the first time ever, my third year class of juniors is totally full at thirty, and so I usually have a lot of drop-off between the second and third year. They get to CAD, and they’re not sure if they’re going to do the third year, and they trickle off. The students who take the classes are students that kind of come in interested in design of some kind. There’s a word-of-mouth component, but a lot of it is like they’ve either heard about engineering or architecture, and they want to explore design, and I find that once I get them in the first class, if CAD doesn’t scare them away I can keep them. But some of them do. They get to that first CAD unit, and they think that that kind of very precise way of thinking maybe isn’t what they’re interested in. So some of them I have to work with them and the rest of the class that they don’t get scared off just by AutoCAD. Because one thing that hasn’t come up that’s really significant about teaching CAD is: part of success in that is visualization. When you’re drawing a three-dimensional object in two dimensions, you have to be able to visualize and abstract that they don’t actually represent the object. Things like hidden lines and center lines don’t actually exist. They’re meant to convey some kind of information. And so there are students that get the software easily but struggle with visualization, and that is a skill that’s really important. Research has shown that visualization skills relate to success in engineering and college.
[Pius] Yeah, so much of a big predictor that they have programs now in college trying to help people get that skill. Do you notice that, that your kids get better at it?
[Audrea] I do. I notice there are some definite innate abilities right away, and that some kids need more assistance. There are some techniques to help them try to visualize. And we do a lot of sketching-type visualization. A lot of it’s not just in CAD, but looking at an object and identifying surfaces, sketching an object in three views, sketching an object as an isometric. They do become more skilled at that. And then the flipside, looking at a 2D drawing and figuring out what 3D – what implications does that have in 3D – that in some ways is harder. When they do their own designs, the object doesn’t even exist yet. It’s just an idea. Then they have to figure out how to draw that idea.
[Pius] And do they do CAD on electrical circuits, too? Because I know you mentioned it.
[Audrea] We’re doing that right now in my advanced CAD. SO they’re making a circuit diagram, which is a totally different way of doing CAD, because it doesn’t have dimension. It’s much more diagrammatic. But it has some advanced tools, what we call attributed blocks and XREFs, that teach them some advanced CAD to make that drawing easier and more accurate. But it’s like a whole other way to do CAD. It just lets them see it doesn’t have to be floor plan dimensions or exact geometries of a part that’s going to be manufactured.
[Pius] And if you had any last advice for schools who may not have an engineering or a CAD program, how can you get one started?
[Audrea] I actually think it’s easy to get one started, because the software is available pretty much for free now. There’s a lot of online tutorials and free resources, and if you just have a little bit of initiative, you can learn it. But I also would tell a teacher to look at their community college. I would tell someone here in Austin to go take Drafting 1405 at ACC , or audit it, and learn it there, and then start teaching what you learn in that. But there are so many resources now for that. And even programs like Sketchup, you know. You could jump in from an architectural end. And the kids are totally willing to jump in with you on that. Don’t feel you have to know everything to start getting the kdis involved in that and learning that software.
[Pius] I’m sure there are resources on YouTube and everything.
[Audrea] Absolutely. There’s so much. I have a few kids who are teaching themselves Revit right now, which is pretty advanced 3D modeling for architecture, and they’re just going through a series of videos that are probably put out by Autodesk and just teaching themselves how to use the program. There are some pretty neat tools out there. My advice is to just jump in and start doing it, and your kids will totally be with you, especially if it’s 3D modeling.
[Pius] Well, thank you Audrea. I appreciate it.
[Audrea] You’re welcome.
[music fade in]
[Pius] Thanks to Audrea for letting me pick her brain on all these tools. If you got something out of this podcast, please subscribe and leave me reviews on iTunes, SoundCloud, or Stitcher, and send me comments on Twitter, Reddit, and Facebook. All of that will help others find the podcast, too. You can find links at k12engineering.net.
[Pius] Our opening music comes from “School Zone” by The Honorable Sleaze. Our closing music is from “Late for School” by Bleeptor. Both are used under Creative Commons Attribution Licenses. The K12 Engineering Education Podcast is a production of Pios Labs. So everybody, until next time, take care.
[Pius] Hey there. It’s Pius again. I’m excited to remind everyone that we’re testing out some new ideas for integrating the arts and engineering at South by Southwest in March 2017 in Austin. Check out our sessions. One is on integrating electronics, textiles, and programming, and another is on using improv and art games to boost your product design skills. Hope to you there in March.