# Tell us an interesting random fact you stumbled across (Part 1) **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [April 13, 2020, 3:19am UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674 "2020-04-13T03:19:22Z")\ **Posts on this page:** 20\ **Page:** 130
**Author:** ![Limmin](https://avatars.discourse-cdn.com/v4/letter/l/f04885/32.png) [@Limmin](https://boards.straightdope.com/u/Limmin)\ **Post date:** [August 31, 2021, 4:42pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2588 "2021-08-31T16:42:21Z")
Nice story, about the need for car engine valves to rotate slightly. I didn’t know about that. It does remind me of something that perhaps not everybody here knows: making a nice, even line when drafting an engineering drawing. I learned, way back when I actually had a drafting class at the start of my undergraduate education (in mech. eng.), that to make a nice uniform line using a pencil and straight edge, to rotate the pencil as you drag it along. I find myself doing this unconsciously when using pencil and a ruler or similar. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [August 31, 2021, 9:26pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2589 "2021-08-31T21:26:46Z")
> [@Limmin](#): > > I learned, way back when I actually had a drafting class at the start of my undergraduate education (in mech. eng.), that to make a nice uniform line using a pencil and straight edge, to rotate the pencil as you drag it along. I find myself doing this unconsciously when using pencil and a ruler or similar. As an artist, I do this all the time when drawing a line with pencil. I thought I was the only person to do this. ---
**Author:** ![EinsteinsHund](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/einsteinshund/32/8400_2.png) [@EinsteinsHund](https://boards.straightdope.com/u/EinsteinsHund)\ **Post date:** [August 31, 2021, 9:42pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2590 "2021-08-31T21:42:11Z")
> [@panache45](#): > > > [@Limmin](#): > > > > I learned, way back when I actually had a drafting class at the start of my undergraduate education (in mech. eng.), that to make a nice uniform line using a pencil and straight edge, to rotate the pencil as you drag it along. I find myself doing this unconsciously when using pencil and a ruler or similar. > > As an artist, I do this all the time when drawing a line with pencil. I thought I was the only person to do this. I don’t understand this. Don’t your lines come out as spirals? ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [August 31, 2021, 9:48pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2591 "2021-08-31T21:48:02Z")
> [@EinsteinsHund](#): > > I don’t understand this. Don’t your lines come out as spirals? It’s the proper technique when using a pencil & straightedge to draw a straight line… while the pencil is moving, you should slowly rotate the pencil. Doing so causes uniform wear on the pencil lead, thus maintaining a nice conical shape. Failure to do this will cause the lead to have a chisel shape instead of a conical shape. ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [August 31, 2021, 9:51pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2592 "2021-08-31T21:51:34Z")
> [@Limmin](#): > > that to make a nice uniform line using a pencil and straight edge, to rotate the pencil as you drag it along. I was not taught this when I learned drafting. But then, I wasn’t taught anything when I learned drafting: it was a formative influence in my opinion of the variance of university-level pedagogy. I was assessed as having ‘bad linework’ when I started, and I still had bad linework 3 years later. ---
**Author:** ![EinsteinsHund](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/einsteinshund/32/8400_2.png) [@EinsteinsHund](https://boards.straightdope.com/u/EinsteinsHund)\ **Post date:** [August 31, 2021, 10:29pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2593 "2021-08-31T22:29:49Z")
> [@Crafter\_Man](#): > > It’s the proper technique when using a pencil & straightedge to draw a straight line… while the pencil is moving, you should slowly rotate the pencil. Doing so causes uniform wear on the pencil lead, thus maintaining a nice conical shape. Failure to do this will cause the lead to have a chisel shape instead of a conical shape. Ah, that makes sense. I’ve never learned this technique. But then, I was never really taught technical drawing, I had to learn it myself. I studied electrical engineering, and one of the first and second semester courses was mechanics. We learned a lot about forces, but nothing about drawing, but both semester papers were complicated technical drawings we had to work out ourselves how to be made. ---
**Author:** ![WolfpackJeep](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpackjeep/32/2921_2.png) [@WolfpackJeep](https://boards.straightdope.com/u/WolfpackJeep)\ **Post date:** [August 31, 2021, 10:54pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2594 "2021-08-31T22:54:44Z")
I had one vaguely-related drafting course in college (despite majoring in mechanical engineering), and I was never taught this technique. I’ll give it a try! ---
**Author:** ![Paintcharge](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/paintcharge/32/7946_2.png) [@Paintcharge](https://boards.straightdope.com/u/Paintcharge)\ **Post date:** [August 31, 2021, 11:28pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2595 "2021-08-31T23:28:34Z")
Do they still teach hand drafting? In my college years, I was the first theatre set designer to take a CAD class, outside of the theatre dept, obvs, and the profs were all wondering why I would want to do that. Over the next 2 years we went from 286 computers to 486’s, but still. My senior year final project was to draft the whole theatre, trap doors, all the fly lines, the proscenium, everything. I’d tell the 'putet to render it in 3d, go get lunch and it still would be working on it. VersaCad IIRC. I think that department is still using a version of my old drawing. Now, even at old school set design classes, I don’t think anyone hand draws anymore. ---
**Author:** ![Andy\_L](https://avatars.discourse-cdn.com/v4/letter/a/c67d28/32.png) [@Andy\_L](https://boards.straightdope.com/u/Andy_L)\ **Post date:** [August 31, 2021, 11:33pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2596 "2021-08-31T23:33:07Z")
Glad to help. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [August 31, 2021, 11:34pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2597 "2021-08-31T23:34:27Z")
> [@WolfpackJeep](#): > > I had one vaguely-related drafting course in college (despite majoring in mechanical engineering), and I was never taught this technique. I’m not sure if teaching it is widespread. I sort of figured it out on my own. Am guessing the same is true for most people who use this technique. (Of course, I’m not saying it shouldn’t be taught; I think it should be.) ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [August 31, 2021, 11:40pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2598 "2021-08-31T23:40:47Z")
> [@Paintcharge](#): > > Do they still teach hand drafting? I attended (Catholic) High School from 1982 through 1986. I took drafting my freshman year, and wood shop the following two years. The drafting was old school, of course; large drafting tables with sliding T-squares. For wood shop, we first had to draw our intended project using everything we learned in drafting class, and produce a complete set of orthographic and isometric dimensional drawings. You could then proceed to fabricate it in the wood shop after the teacher approved your drawings. The teacher - Mr. Marvin Paule - was an old Navy vet. Very rough around the edges and tough as steel. Great guy, though. Died in 2009. I learned a _lot_ in those classes. I wouldn’t trade that experience for anything. I don’t think many high schools offer shop anymore. Am guessing it’s due to the fear of lawsuits from a student getting hurt. 😧 ---
**Author:** ![Yllaria](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yllaria/32/3452_2.png) [@Yllaria](https://boards.straightdope.com/u/Yllaria)\ **Post date:** [September 1, 2021, 3:16am UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2599 "2021-09-01T03:16:58Z")
I remember the first time I used my college’s drafting room. I went to sharpen my pencil and instead of making a point, the sharpener just shaved the wood away from the graphite, leaving a naked cylinder of graphite hanging on the end. The older students were amused and showed me how to use the little file from my drafting kit to make a point. > [@panache45](#): > > When I quit smoking in 1979, a carton cost about $10. I thought that was a lot. That reminds me of one of my grandmas-in-law. She had a series of events that put her in the hospital. While she was there, she couldn’t smoke either because she was on oxygen or because her roommate was. Then when she got out, she was a little less habituated AND the price of cigarettes had gone up. After the third or fourth hospital stay, she gave up on them. ---
**Author:** ![digs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/digs/32/14889_2.png) [@digs](https://boards.straightdope.com/u/digs)\ **Post date:** [September 1, 2021, 3:30am UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2600 "2021-09-01T03:30:47Z")
> [@Crafter\_Man](#): > > I took drafting my freshman year… This brought back memories! Of a drafting class in junior high, where I was so excited to use all the tools… I mean, with a T-Square and a triangle, you could draw a perfectly horizontal or vertical line! We were pretty young to be doing isometric drawings\*, but we loved it. _Much_ later, as a design teacher, I made sure students knew how to draw by hand as well as on the computer… \*(Thanks, Mr. Hess, even if you did throw a piece of chalk full force at my head when I was whispering during a lecture) ---
**Author:** ![Slithy\_Tove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/slithy_tove/32/18248_2.png) [@Slithy\_Tove](https://boards.straightdope.com/u/Slithy_Tove)\ **Post date:** [September 1, 2021, 3:47am UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2601 "2021-09-01T03:47:23Z")
My Dad had a 1950’s draftsman’s kit, some of which I took to art school later. Not the clear French curve guide shaped like a woman (similar to the chrome woman seen on mud-flaps), but definitely his T-square, adjustable protractor triangle, foxtail brush and the little pillow filled with rubber crumbs. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [September 1, 2021, 10:38am UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2602 "2021-09-01T10:38:35Z")
> [@Paintcharge](#): > > Do they still teach hand drafting? Probably not. My freshman year of college was in the late '80s, and I had a hand drafting class. Pencils, straightedges, drafting tables, T-squares, french curves, stencils, all that stuff. Turned out that was the last year for all of that: the next year, it all got replaced by CAD. Since that was pretty early CAD software, I’m guessing the students still had to learn all of the concepts of projections, hidden lines, and so on, but they were no longer being taught how to properly sharpen a pencil or draw a quality line. I wonder if engineering students these days get thrown right into solid-modeling software, or if they start with 2D CAD? ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [September 1, 2021, 11:20am UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2603 "2021-09-01T11:20:43Z")
> [@Crafter\_Man](#): > > I don’t think many high schools offer shop anymore. Am guessing it’s due to the fear of lawsuits from a student getting hurt. 😧 A kid in my high school class lost 3/4 of a finger to a bandsaw in shop class. He was an ass; the kid you’d vote “most likely to lose a finger in shop class”. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [September 1, 2021, 1:08pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2604 "2021-09-01T13:08:49Z")
I’m also wondering if the skill of fabricating something by hand - based on a complex blueprint - is gone. There used to be a technical trade called a **[patternmaking](https://en.wikipedia.org/wiki/Pattern_(casting)#Patternmaking)**. These were highly-skilled fabricators (called patternmakers) who would make things from wood or synthetic materials. Negative molds would then be made from the specimens. My uncle was a patternmaker, and I would occasionally visit his shop. His specialty was steering wheels for General Motors, Ford, etc. He would make the wooden steering wheels from a blueprint. Once finished, the (wooden) steering wheels would be used to make the negative molds. It would take him weeks to fabricate one. I used to be in awe of the blueprints… they were incredibly complex looking, and it amazed me that a person could understand one and make something from it. ---
**Author:** ![digs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/digs/32/14889_2.png) [@digs](https://boards.straightdope.com/u/digs)\ **Post date:** [September 1, 2021, 1:13pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2605 "2021-09-01T13:13:46Z")
And I bet back then they were blue! I miss those, such an iconic (but now dated) look… ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [September 1, 2021, 1:43pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2606 "2021-09-01T13:43:51Z")
> [@Machine\_Elf](#): > > > [@Paintcharge](#): > > > > Do they still teach hand drafting? > > Probably not. My freshman year of college was in the late '80s, and I had a hand drafting class. Pencils, straightedges, drafting tables, T-squares, french curves, stencils, all that stuff. Turned out that was the last year for all of that: the next year, it all got replaced by CAD. Since that was pretty early CAD software, I’m guessing the students still had to learn all of the concepts of projections, hidden lines, and so on, but they were no longer being taught how to properly sharpen a pencil or draw a quality line. I wonder if engineering students these days get thrown right into solid-modeling software, or if they start with 2D CAD? I started college for mechanical engineering in September 1984 and graduated in May 1988. We were never taught hand drafting and I only learned some CAD (CADAM, I think, and perhaps also CATIA) because of an elective course I took. I vaguely remember being told that we were only expected to be able to do a back-of-the-envelope sketch that would then be executed by a professional draftsperson. And the CAD software was run on terminals with huge CRT screens with a lightpen in a computer room with a raised floor and chilled air coming up from below. (So that when my roommate and I spent an overnight working on a project, I was really cold in the middle of the night.) ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [September 1, 2021, 7:11pm UTC](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674/2607 "2021-09-01T19:11:25Z")
> [@digs](#): > > And I bet back then they were blue! > > I miss those, such an iconic (but now dated) look… My very first job, in the early '60s, was as an office boy in an architect’s office. One of my duties was feeding black and white drawings into a blueprint machine, which transformed them into white lines on a blue background. I could never figure out why they were preferable to the original black and white ones. [Previous page](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674.md?page=129) [Next page](https://boards.straightdope.com/t/tell-us-an-interesting-random-fact-you-stumbled-across-part-1/851674.md?page=131)