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Comment by PostOnce | Hacker News Reader

A 3D printer has taught me mechanical engineering like my computer taught me programming

This!! It's also given me a lot of insight into industrial design. As in how do you make something strong in the right places yet not use too much material. I'd seen the result of such choices when opening up devices but the "why" never sank in.

Obviously this is not a super important thing in the scope of our world and my day job. But still, it feeds my curiosity (as does this site) and that alone is more than worth the investment to me.

Also, being able to design and manufacture a plastic part in a matter of hours any time of day or night has become a really useful tool. Only a few days ago the window latch on the front door of our apartment broke off and we've already had too many break-ins. It was too late in the day to go buy a new one but the printed one works really nicely.

That's ("how to make something strong the right places") is not really industrial design though (but mechanical engineering). Industrial design of course also take that into account, but it's more about making it usable and the aesthetics of it.

Sorry for nit-picking.

Although this seems to me like saying "learning BASIC has taught me Computer Science" -- yes, the principles of MechE can be learned by study + some actual 3D printed models. But to truly grok MechE, you need mastery of some CAD program (OpenSCAD is my choice, but I also use FreeCAD), and the ability to fabricate in some other materials (metals) using subtractive methods. Plus, you know, a little math here and there...

I like your reasoning tho; I got mine when it was on sale, and just before the pandemic - so I have plenty of learnings about PLA, ABS, PETG, temperatures, glue or not, surface, and most of all -- plenty of piles of material creating 'modern art' rather than my planned masterpieces. '-)

I think you took this the opposite way. My interpretation was that using a computer (web browsing, editing word documents, whatever) doesn't teach you CS. In the same way, using a 3D printer doesn't (by itself) teach ME.

Well-put.

Perhaps, distilled, it's this: having a 3D printer, by itself, won't turn you into a MechE. But, if you do have a 3D printer, you can learn the basics of ME and try out some practical ideas with real parts.

I specifically got my 3D printer to make gears. I do have a Sherline mill, as well as a 12" (Chinese) lathe; so I do have the specific tools to create involute gears out of metals. However, since I planned on doing so many different gears, as I wasn't really sure what I needed, AND the fact that with subtractive manufacturing, if you make certain mistakes, you throw the whole piece away and start over -- 3D printing makes creating new parts as trivial as starting it up again. The other total win of 3D is e.g. Thingverse where you can d/l a design -- it's the closest thing we have to Star Trek's replicator.

Lastly, Michael Faraday wrote an entire book on candles. https://en.wikipedia.org/wiki/The_Chemical_History_of_a_Cand... So much can be learned from little!

Nowadays you don't even need 3D printer, but waiting a week or three for cheap 3D printing services kinda kills the momentum for learning...

Out of 120 credits for my ME degree, only 2 were CAD (directly).

Mechanical engineering consists of learning tools for analyzing designs, such as fluid mechanics, materials, solid mechanics, thermodynamics, statics and dynamics, control system theory, etc.

Thanks. When you say "learning tools for analyzing designs" -- do you mean calculus, differential equations, other math and such? Or do you mean "XYZ Software Tool for Fluid Mechanics" etc?

They mean fluid mechanics, materials, solid mechanics, thermodynamics, statics and dynamics, control system theory, etc.

You need all of that math to understand the topics, then you can apply them to real life. FWIW you can probably be a decent design engineer with an industrial engineering degree plus some thermo, circuits, dynamics and a lil CS... I see more than a few jobs open up that accept both degrees.

I think you can really pick up Fluids, vibrations, and advanced mechanics on your own with that background, if you end up needing it. But to the larger question, yeah you need calc 1-3, ODEs, and actually a good bit linear algebra to be able to understand and apply 300-level engineering and beyond.

It's not mastering mechanical engineering that it teaches you. But just a basic hands -on understanding that is very useful in the life of a maker with a broad range of interests.

Becoming a wizz at industrial design was never my goal. There's universities for that. But it's wonderful to see how everything comes together.

Also, imagining something only in your head and then seeing it come to life on the screen and then in the real world is a magical thing.

I guess carpenters and sculpters etc get this all the time but I totally lack the manual skills needed for that. The 3D printer solves my handicap of having two left hands.

Most people that buy a 3d printer download some models from thingiverse and then get bored with it. It's when you learn design that it really becomes amazing. And it's not all that difficult at all.

Definitely made learning a bit of CAD more interesting when you can actually apply it to real life.

My favorite CAD story came from around the time when the ability to create 3D renderings from the plans came around. The company my dad worked for had a disagreement on the location of a set of pipes running along a corridor. Once the 3D render was available, it was clear that the plans were very wrong and would have placed the pipes in an impossible manner. I never did learn why the CAD ops were so sure they were right, but just one of those funny stories that stuck you just made me think of it again.

Just a minor nit. Mechanical engineering ain’t additive manufacturing. And CAM isn’t mechanical engineering. Also 3D printing and CNC, which creates far stronger parts, are quite different. CNCing ferrous and non ferrous metal is quite challenging - but again, this is CAM which is more a machinists job, not a mechanical engineer.

It works the other way around too. Got some nasty scars from disassembling cheap PC cases. That told me a lot about stamped sheet metal and costs-cutting in assembly lines.

On the other hand, no better way to learn an STM32 and automatization than looking into Prusa Mini firmware github ;-)

Yeah, that was my experience. Now I just model stuff in Blender and haven't printed anything in a while. I'll probably get back into printing stuff once I get a new storage solution for my filament (and install some of these upgrades I've been sitting on for a year).

You just added more evidence to my theory that there are a lot of 3D printers sold to "enthusiasts" where it sits in a corner covered by a sheet just like a lot of grease monkeys have a car in a garage covered by a sheet that one day will get restored.

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