Intermediate Technical Sketching

December 2, 2008 6:44 AM

Other than the practicing I'm already doing, how can I learn more about technical sketching?

Perhaps the best way to start to describe what I'm talking about is define it as the intersection of two broad and easy-to-find-information-about fields

1) Freehand sketching
2) Drafting/technical drawing

I'm not trying to draw fruit or people or things I can physically see. I'm not trying to give exact dimensions and 3 projection views, nor do I want to draw each machine part separately. I'm trying to draw things like beams and linkages and gears and nuts and bolts freehand, all put together and in design mode.

The "complete beginner" basics are already completed. I have pencils and so forth. I can draw lines, circles, ellipses, etc. What I need help with is how to draw something complicated like a gear. Or how to indicate different materials. Or how to do a cutaway/cross-section.

Obviously there are some things from each field that apply to this, but I am having trouble finding information specific to this task. Even old drafting books skip lightly over the freehand chapter and then get right into formalized drafting. Architectural sketching books seem to come closest, but that is mainly concerned with buildings (duh) not machines. A previous AskMe elicited a reply that seems nearly perfect except for two problems.

1) The book is very short. Worse, it looks like the material I'm interested in is only in 2 or 3 chapters.

2) The book is not in any of the many libraries available to me.

Many different googlings yield results, but they are mainly of the "first, get some pencils" variety that peter out quickly without getting anywhere. I have found reference to various books with titles like "Freehand Technical Sketching" but there's no information beyond the title to see what's really inside and if it's worth paying money for.

Maybe no such resource exists? In which case, who are some artists and/or engineers who've figured this stuff out for themselves? Perhaps I could just look at what they do.

posted by DU to media & arts (15 comments total)

My guess would be technical drawing classes. I'd think that engineers who make rough sketches probably have a goodly amount of TD training. I did TD for a few years at school and although I don't have much use for it, I'm glad I did. There will be evening classes somewhere if you have the time.
posted by mandal at 8:31 AM on December 2, 2008

And, yeah, sorry, because that probably told you very little you didn't know and likely wasn't that helpful. Bad mandal.
posted by mandal at 8:32 AM on December 2, 2008

I actually did not even think of classes. I don't think I can/want to spend the time and money of a class, but presumably a class uses a book though, right? Or not?
posted by DU at 8:36 AM on December 2, 2008

I agree with mandal, although that might not be the answer you're looking for. Learn technical drawing and then do it without a ruler, having developed a sense of scale and proportion through a lot of practise.

I work in architecture and this is what everyone does - buildings less often than details of the junctures between components and materials. It's the day-to-day workings of an office, developing details which are then either sent as-is to site or drawn up as hardline drawings for issue.

Off the top of my head, David Adjaye is an architect who tends to publish his (beautiful) details, but I can't remember if any of them are freehand. Leonardo da Vinci?

I'm not sure if it would work out, but looking into something like medical illustration/scientific illustration might be fruitful if you're hitting nothing here. Sure, it's tissue and bone and all that, but it strikes me as being very similar in style and purpose. If you could study and draw in the style of Grey's Anatomy, you'd probably be able to draw anything.
posted by carbide at 8:43 AM on December 2, 2008

Oh, I did take drafting (with an actual pencil on an actual drafting table) in high school. I know some of the absolute basics. I've been drawing designs of stuff for a while now and it's worked out OK. It lets me figure out details that otherwise I'd have to be in the workshop to figure out (which isn't necessarily a good thing...), document more-or-less what I've built, etc.

But now I want to make the drawings look a little better. They are already a few notches above napkin level. I wanted to introduce some shading and whatnot. Cool cutaway views. This is a fair example. It's more formal, not to mention busy, than what I'm talking about, but the style is there.
posted by DU at 8:57 AM on December 2, 2008

What I need help with is how to draw something complicated like a gear.

In order to draw a gear well, you probably have to understand how it works. Even spur gears have a complexity in the tooth shape that is called an involute curve, which causes the surfaces of the gears to roll rather than slide when they mesh. Other classes of gears allow some sliding between meshing teeth - for example, hypoid gears that you might find in a car's differential. If you are only interested in giving the -suggestion- of a gear then you might find that indicating the root, pitch and outside diameters will suffice.

Or how to indicate different materials.

This is a standard and you have many standards to choose from. ANSI (US) standards, European (ISO) standards, Japanese (JIS) standards and for all I know Russian standards will indicate different materials with different kinds of hatching.

If you can lay your hands on I. Artobolevsky's Mechanisms in Modern Engineering Design (out of print, rare, but sometimes found in engineering libraries) you'll get a set of examples that are both ingenious and well-crafted. A reduced cut-set of similar illustrations is found in the old translation from the German of "The Way Things Work" - which appears to have been re-issued and which I've not seen. You'll also find a frustrating and sadistic bunch of sketch-like drawings in dynamics texts like Meriam's Dynamics, a standard text for undergraduate engineers.

This isn't trivial, especially when I look at your example on preview. If I'm able to do any engineering sketching at all, it's because I did the old ink-and-vellum, formal technical drafting for some years.
posted by jet_silver at 9:19 AM on December 2, 2008

Speaking as a fine artist...

1. I'd suggest learning the principles of perspective. This is key to drawing anything in just about any environment, especially "technical" looking things (vs. say, trees). You'll want 1-point, 2- and 3- point perspective.

2. What you need to refine is your drawing skill. It does not really matter what you draw - ie. there's no great difference between drawing wooden blocks or still lifes and drawing something "technical"... if you can draw one, you can draw the other. So I'd suggest working a variety of subject matter.

3. Yes you will want to cultivate a style - use of shading, shadow, perspective etc. I'd suggest experimenting with different approaches as you grow more skilled.

Hope that helps!
posted by ecorrocio at 9:30 AM on December 2, 2008

I regret my example, which is more detailed and formal than I intended. I doubt I need involute curves, unless I happen to have a big, foreground gear in a head-on view.

If the material hatching standards actually look like that material, I'm interested. If it's a formal convention only, never mind.

It looks like my engineering library may have "The Way Things Work". It doesn't say if it's German, but it's not the similarly-named Macaulay book¹ and is from 1967, so that's promising. (Upon a "preview" to the library: Yes, that's what they have all right!)

¹Then again, the similarly-named Macaulay book may be a good place to start. His drawings are almost exactly the kind of thing I mean although again, his has a lot more detail than I'm looking to put in. I've checked out his books before, but for the content instead of the form.

Thanks for the ideas!
posted by DU at 9:44 AM on December 2, 2008

What I need help with is ... Or how to indicate different materials. Or how to do a cutaway/cross-section.

I can think of some architecture and landscape architecture drawing books that will have some information on these. Maybe you could go to a library and photocopy the best sections. Some of the best, I think, are by Francis D. K. Ching. I personally prefer A Visual Dictionary of Architecture and Architecture: Form, Space, & Order, but he has some books explicitly about drawing techniques as well (the "Look Inside" views on Amazon really don't do the books justice). For some info on showing textures, you might also check out Grant Reid's Landscape Graphics as well. But, like others, I learned more from teachers in classes than from any book.
posted by salvia at 9:50 AM on December 2, 2008

Much of this will be focused on product design sketching, but I'd think the techniques will cross over easily enough to what you want to do:

Sketching: Drawing Techniques for Product Designers could be an alternative to that Swedish Design Sketching book. I haven't seen it myself, but you may have an easier time finding it.

J.D. Orr teaches workshops and classes, and he's got instructional materials you can order. People tell me he's really inspirational.

The Basic Perspective Form Drawing DVD from my previous answer was popular with our students. So popular that it was stolen. Scott Robinson has more DVDs with Gnomon Workshop.

I'm not a fan of anime, but I did see a "How to Draw Anime Robots" or some such title that looked interesting. Lots of emphasis on varied line weights.

I have Francis D.K. Ching's Design Drawing. While it's focused mainly on architecture, the chapter on form and structure would be right up your alley.

One tip, and it's also something you'll get from the sources above, is to lay out as many light constructions lines as you need, and leave them as part of your drawing. It's very different from the formal style of your example. But it'll make your drawings more dynamic and it helps both you and viewer see the perspective, even if you were a little off.
posted by hydrophonic at 10:02 AM on December 2, 2008 [2 favorites]

The Orr fellow looks a little hokey and I think I know the "anime robots" link you found. Was it steampunk rather than anime?

All your other links look awesome, just like before. Thanks!
posted by DU at 10:19 AM on December 2, 2008

Some of the best, I think, are by Francis D. K. Ching. I personally prefer A Visual Dictionary of Architecture and Architecture: Form, Space, & Order, but he has some books explicitly about drawing techniques as well (the "Look Inside" views on Amazon really don't do the books justice).

Yeah, Ching actually has a graphic standards book, as well as "Building Construction Illustrated" which has some (sorry) formal conventions for material indication (when drawn in section) in the back. I don't have the book, but his graphic book has some samples of indications to use for materials drawn in elevation at various scales, but those are typically things like brick or other masonry, wood siding, and concrete rather than machine parts.

The two most basic techniques that you need to master for drawing though are lineweight and how to draw corners. They're not the most obvious things, and even working in an architectural office, I see improper lineweights used all the time, but those two things can add a great deal of clarity to your drawings. Again, Ching provides good examples of this, but more through the drawn examples in his books rather than through actual instruction. The lineweight thing is just something you have to get a feel for. The corner thing is pretty easy though -- just overemphasize them. You actually want to overshoot the intersection of two lines a little bit and draw the ends of the line segments a little more strongly than you do the rest of the line. Don't draw a rectangle without picking up your pencil; draw four slightly overlapping line segments. For whatever reason, it just looks crisper that way, and the right look will come with practice.

Lineweight depends on what kind of drawing you're doing. If you're drawing materials in section, as if you're cutting through them, then the outside line of the cut should be the darkest line of the drawing while interior lines should be de-emphasized. Material indication lines should be the lightest lines you use. If you're drawing in elevation, like you're looking at the outside of something, things closer to you will have heavier lineweights, while still having a fairly heavy outer line. This takes a little more time to get a feel for.
posted by LionIndex at 10:23 AM on December 2, 2008

Gnomon for sale
Gnomon for rent
Another good design vid for rent
posted by dpcoffin at 11:02 AM on December 2, 2008

The Orr fellow looks a little hokey and I think I know the "anime robots" link you found. Was it steampunk rather than anime?

Yes, it's a shame Orr went with the awful infomercial production values.

The "anime robots" thing was an actual book in the hands of a student. This was back in the days before steampunk. I did a few searches and didn't find anything to recommend, but I'm sure a trip to Border's or the comic book shop will turn up something.
posted by hydrophonic at 11:08 AM on December 2, 2008

As a quick little followup: I got Francis D.K. Ching's Design Drawing from the library. I've mainly just been reading (i.e. only doing a few exercises) and I'm only a few chapters in, but it is pretty awesome. I think this is exactly the kind of thing I was looking for. I'm mainly learning how much I have to learn.
posted by DU at 6:40 AM on December 8, 2008