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Re:How to Build a 50K Ton Forging Press by kragen on Wednesday August 21, 2024 @05:10PM (#41314223)
there's a lot of shade-tree mechanics who have successfully rebuilt engines with thousands of parts. essentially figuring out how to rebuild an engine is similar to figuring out how to build one from scratch, which is within human capacity, particularly with background knowledge. but the guy rebuilding the engine has a lot of hints

granted, he'll probably fuck up his first two or three pretty good without haynes or chilton

Re:How to Build a 50K Ton Forging Press by rlonstein on Wednesday August 21, 2024 @07:37PM (#41315251)
> granted, he'll probably fuck up his first two or three pretty good without haynes or chilton

Given the assumptions, inaccuracies, and mistakes I've seen in some Haynes and Chilton manuals they'll probably fuck up with them. Factory manuals are usually worth the price (Honda's are, KTM's not so much).

Re:How to Build a 50K Ton Forging Press by kragen on Wednesday August 21, 2024 @08:28PM (#41315540)
i certainly did. haynes is no substitute for clue
Re:How to Build a 50K Ton Forging Press by hinkley on Wednesday August 21, 2024 @05:53PM (#41314555)
There is a lot of stuff you can do when it’s pass fail. As a pro you have a time limit and you’re bad if you can’t rebuild in X hours.

My dad will tell you I helped him rebuild a bike coaster brake at 14. But the truth is the only decision he made was to buy the repair kit. I got rags and laid all the parts out like an exploded diagram, we cleaned them or swapped them and they went back in the way they came out.

I worked as a bike mechanic for two summers in college. Cars have manuals and maybe the mechanic you work for has them. Bicycles do not. You’re all shade-tree until you’ve seen everything a couple times.

Re:How to Build a 50K Ton Forging Press by kragen on Wednesday August 21, 2024 @06:54PM (#41314979)
yeah. thank god for sheldon brown
Re:How to Build a 50K Ton Forging Press by hinkley on Wednesday August 21, 2024 @09:43PM (#41315917)
I was more of a Brandt boy myself.
Re:How to Build a 50K Ton Forging Press by bacon_waffle on Wednesday August 21, 2024 @10:19PM (#41316165)
I've rebuilt several motors, transmissions, various other mechanical contrivances. Sometimes with decent documentation, sometimes not so much. Also done a bit of amateur machining, and worked as an engineer on physical products.

Under no circumstances would I claim that rebuilding a motor was essentially figuring out how to build one from scratch. In software, maybe that's like claiming that figuring out how to configure a new Linux box is essentially the same thing as figuring out how to write an OS.

Re:How to Build a 50K Ton Forging Press by kragen on Wednesday August 21, 2024 @11:21PM (#41316514)
yes, i agree. what i was trying to express is that rebuilding a motor is generally strictly easier than building one from scratch, because it's building a motor from something more than scratch. i don't think i expressed it very well

(i mean, if all the parts of your engine are trashed, you are going to have to machine replacements for them, and that might actually take you longer. but it's clearly achievable given that people have built internal combustion engines without a working example to take measurements from)

Re:How to Build a 50K Ton Forging Press by bacon_waffle on Thursday August 22, 2024 @12:13AM (#41316750)
Ah, that helps, thanks.

It's a bit academic, but set theory doesn't really apply to such fuzzy human things as knowledge and experience. Repairing and designing are different pursuits which might have a lot of similarities, but I wouldn't presume that a design engineer could competently do the work of a technician.

Just consider that any particular field of engineering as might be described by a lay person, can be far too broad and deep for an individual to be competent in all facets of it. I'm reminded of my neighbour asking for some help configuring email for her new iPhone, because she knows I do computer work. Mainly firmware.

Re:How to Build a 50K Ton Forging Press by kragen on Thursday August 22, 2024 @12:22AM (#41316793)
there's something to that, for sure; there are plenty of design engineers who don't know nearly as much as they think they do, and who depend heavily on the expertise of their technicians to get anything done in the real world. they could never build an engine on their own! but there are also others who are eminently capable at the technical level, and i think their designs benefit from that

repair and design have in common that they require a lot of hard thought about the causal relationships involved in making the artifact work, tracing the causal chains through until they break, then patching them up. but they both also certainly involve other skills that the other does not; design also requires figuring out how to make new things happen, which involves imagining things that have never happened, while repair also requires knowing how not to bust your knuckles or spill the gasoline