Teaching Drafting

Technical Inventor
1

I began teaching drafting at the beginning of this school year as a substitute, and it has turned into a long-term position. I have no drafting experience.

Our administrators have not found a teacher yet, so I will be teaching it again next semester.

What I have done for the most part so far is to teach the basics of AutoCAD that I have learned from manuals. For assignments, I have had the students draw things that I have picked out of old drafting textbooks.

So my question is this: Am I on the right track? I hate to think that I am boring them to death with all of these drawings, but then again some of them still don’t have the hang of it.

HELP!!

Mark Slattery

2

you could always tell them to design a house,a floor plan, that should be along term project of creativity. and if you have a drafting blue print printer avaliable too it will all be worth it

-Osc-

3

Mark,
The nice thing about Autocad is this… If you think that the software should be able to do something, Autocad already does it.
The bad thing about Autocad is this… You don’t know what Autocad has named the function you want to use.
My suggestion would be to give the students a liittle basics then use what you have learned to draw something. Each class period throw in some more stuff and more drawing. Start with drawing lines, then join the lines. An explanation of the pick boxes on the screen and toggles at the bottom is a must. In the beginning just display the basic toolbar then add in more toolbars as you progress to other commands. Make a 2d drawing using lines i.e. a simple house or building. Then introduce object snap to draw from objects that are already drawn. A little easy dimensioning then on to more complex objects like circles and polygons, a little more object snap, a little more dimensioning. Some text using monotext, to demonstrate text insertion, then draw from text object snap and a little dimensioning.
At some point you need to set a goal list. I am sure that Autodesk must have something on their website that should help. Although each user does things differently, I prefer my users to get the hang of drawing with object snap and NO SNAP OR GRID turned on. A good, clean drawing should have all lines meet and that is extremely easy when you are drawing with reference to objects that are already in the drawing. You might have students take real life objects and convert them to drawings using dimensions they measure on the object. Eventually work in the power of layers, poly lines, zoom, and edit functions. If you have the time, move into 3D drawings with the same objects they had previously drawn in 2D. At one time, Autodesk had included some kind of teacher’s aid that allowed you to only enable the commands that had been already covered but I don’t know if the modern versions still do that.
I kind of rambled on there, but I think you get the big picture. Although Autocad is so much more precise than drawing with pencil it is so much more easy.

4

One of the difficulties with drafting is that the student must take a 3D item (say, a robot part or a building) and translate it into a 2D medium (paper or computer screen). Some people naturally have good spatial aptitude. The students who aren’t catching on probably don’t have it–yet. If you put a cylinder, such as a water glass, in front of them, they will draw the top as a circle, not an ellipse. They will need extra help just learning the 3D to 2D concept.

It seems to me that going straight from no knowledge of drafting to a CAD program is too great a leap for most people, anyway. You could start with the basics: have some solid cubes (building blocks, sugar cubes, whatever), and make sure all the students can sketch one cube from the standard perspectives (plan, elevation, isometric, etc.). Then have them sketch arrangements of 2-3 cubes. Using colored blocks and pencils may make it easier for students to see the spatial relationships. Then, they can do more complicated arrangements, then sketch things like Lego models, or work with pictures from books.

Their lines don’t have to be straight, and their lettering doesn’t have to be neat. The point is to develop their ability to see how their 2D sketches relate to 3D reality; that relationship has to be accurate. (If the red block is on top of the blue block, it must be that way in the sketch, too.) They’ll need close to 90 degree angles in the plan and elevation views, and highly flattened angles (60 & 120 degrees) in isometric view. Make sure they have graph paper and isometric paper so they can focus on sketching, not getting their lines and angles straight.

Once the students’ spatial reasoning has been established, then they are probably ready to learn the conventions of drafting, both on paper and CAD.

I had my son go through a curriculum called DIME 3-D Sketching Project, from Spectrum Educational Supplies, which did what I have described above, and it gave him a lot of confidence. There are three books, which are written for ages late elementary on up. It would cost a bit of money to get the books, which are reproducible, and the special set of blocks. Go to Spectrum

There is also a book call Practical Drafting, which is designed for students ages 12 and up to use on their own. It’s an overview of many different drafting applications (way beyond sketching simple blocks). Go to
Insight Technical Education
This particular web site has a brief sales pitch for the benefits of learning drafting, in case you have some reluctant learners who don’t see those benefits.

As far as boring the students, you can avoid doing that if you sometimes let them draft real-life things they like or need to draw, such as robot parts, model cars, even clothing patterns. Just insist that the drawings accurately reflect the real thing, though you may need to simplify. This should be a fun course, and I hope you and your students enjoy it.

5

Yay!! 2d drafting at it’s finest!

OK, I have a little bit of experience in this as CAD is my major in college.

First things first. Make sure they know their 4 coordinate areas and which one is standard.

X and Y axis’ and all that fun stuff.

Standard position, bottom left corner of a square for example is in standard position in co-ordinate area 1, and at point 0,0 (for now, don’t worry about z… yet.)
The fact that on standard position, 0 degrees is to your right, 90 is top, 180 is left, and 270 (or -90 which is easier) is the bottom. A lot of this stuff is taught in geometry, or algebra or physics as well, so it is something that they will use in other classes. So make them learn it no matter how much they complain. :ahh:

Second thing is the basic layout and way to draw. Introduce them to the line command and circle, and the rest of the commands. (all 3 ways to do them is best to know as well (command line, icon, and menu’s))

Then, the fun part begins. (sort of.)

The learning of the polar coordinates, or the rectangular coordinates.
ie: for a square of 1 unit length and 1 unit height the options are:

line <enter>
0,0,0 <enter>
@1<0 <enter>
@1<90 <enter>
@1<180 <enter>
@1<-90 <enter>
<enter>

or

line <enter>
0,0,0 <enter>
1,0<enter>
1,1 <enter>
0,1 <enter>
0,0,0 <enter>
<enter>

In my opinion, the first way is the easiest, and most practical.

Then, what we did was make dumb shapes and as the time went by the shapes got more intricate. ie: a circle in the middle of an ellipse, and two holes on the sides. It looks like a funky gasket after we were done.

Oh, and while you are teaching Autocad, don’t forget about some standard drafting principles as well (hidden lines, sections, cross hatching, etc.)

Wow, sorry I went on like I did, but as you can tell I have been doing this for a while. It’s fun once you get the hang of it, and then you find even faster ways to do the things it took you about 5 or 6 commands to do the first time you learned it…

When I look back at my first CAD class, and more shocking, look back at the stupid shapes I had to draw to pass that class, it’s a wonder I made it through. It’s not that it was hard, but the fact that making a couple of circles in different required shapes and points on the area took me about 20 minutes to do. With what I know now, I can make 3D parts in CAD for the robot and dimension them all and produce a complete set of prints in the same time.

6

Karen and Elgin have provided awesome advise. I have taught Drafting at a local college for a number of years. Unfortunately, they dropped the mechanical drafting requirement and replaced it with Computer Aided Drafting. I started my professional life as a board draftsman for Fisher Body. Later, I was one of the early CAD designers. I am a big believer in understanding the principles of 2 dimensional drawing, before creating Math Models. Your observation that “some students don’t seem to get it” is normal. Students “get it” at different paces - unfortunately some never do “get it”, as they don’t have the ability to transform the 3 dimensional object into a 2 dimensional picture. My experience and advice aligns with both Karen and Elgin. Make sure that you really stress the principles - even though there are alot more glamorous topics that could be covered. If you do want to make it a bit more interesting, have the students draw a real world object - my favorite is a Table Top Vice. Just make sure that the objects being drawn are based on simple geometric shapes - then work up to the more complex. Good Luck in teaching this important lost art.

7

Generally I would start off with the basics. Ornotgrathpic way of looking at stuff and the cube way of looking at things. All you have to do is imagine the object you are drawing is in a cube. From there you can orientate the object in order to get a feel for how you are going to create the drawing. Personally I learned only three differnt ways of drawing things in my technical drawing course and I used paper and pencil:). Three view, isometric, and oblique are the three types I used my high school course. I haven’t even drawn three dimensional shapes yet in college.

8

As a 9 year teacher in Technical and Architectural Design as well as the Introduction to Engineering Design course in the Project Lead the Way program, I fully agree with all of the suggestions you’ve given at this point. However, we can’t forget that AutoCad, Inventor, Pro E, Unigraphics, etc. are all “tools” to be used to teach certain drafting principles such as orthographic projection, dimensioning principles, pictorials, sectioning techniques, auxiliary views, working drawings, and so on. I feel this information is much more critical in a drafting class than the software itself. Any of the “old drafting textbooks” you have will give examples on how to accomplish these types of problems and I would suggest giving varying assignments in each of the major categories to see that the students receive a wide array of knowledge by the end of the course. I know as well as you do that kids don’t all learn at the same pace… you need to be very flexible and patient.

Best of luck and if you ever need help, please feel free to contact me through e-mail for ideas and suggestions.

9

Wow,

This is pretty crazy. I was just hired as a substitute to teach 2 sections of engineering design graphics. Classes start the 29th.

In my case, we’re completely changing the curriculum. Moving more towards teaching the basics of design and drawing packages, rather than just all the bells and whistles that ProE has. There is another lab in the curriculum that has students machine a hammer from 2 pieces of cold rolled. So that’s our focus for the drafting class. Week one they extrude a box and a cylinder, create an assembly, and make a drawing of each part. From their, we’ll go back and add in all the detail, work with the parametrics of changing a hole diameter on the hammer head and having it change the diameter of the handle, and creating families of parts, where you can have a centerpunch or a screwdriver stored inside the handle. Also determining weight based on properties, creating an injection mold to create the hammer and other things.

The whole class stays relative and actually provides a lot more relavant information than when I took the class. It’s kind of like what a professor told me. It’s like using a calculator. When you get one, you’re not going to sit down and read the instruction manual. You’re do what you can with what you know. When you need to move beyond that, you’ll then turn to the manual and figure it out. Give 'em basics.

Good luck!