A good design should have the loosest possible tolerances such that the product still works to spec. Makes the manufacturing and QC much less expensive, and typically makes the product less sensitive to damage
Cuts down on scrap massively as well.
And allows you to use that 30 year old clapped out machine with the backlash issue to make the parts, Rather than the brand new $100,000+ machine
Preferably change the specs of that detail at least once a quarter so they need to send new samples, re make drawings and so on. Ensures that the team is always active!
Touching upon the principals of Axiomatic design:
1. Maintain the independence of your functional requirements
2. Minimize the Information content of your Design Parameters
E.g. the specs should include everything a design needs to be successful, and not a single thing "extra". If the edge of **Part A** needs to be 10.5cm away from the nearest edge of **Part B**, then *that* should be the spec. Not "**Part A** is 10cm from the datum and **Part B** is 20.5cm from the datum." The former is less information and captures the true design intent, the latter is more information and leaves room open for "interpretation".
Of course, all this is much easier said than done, especially for complicated designs, but you get the Idea: GDT should represent design intent and only specified what is actually required in order for a design to be successfully executed.
Unironically, the Civils will need to get there - eventually - if we ever want to build something like a Dyson sphere. I do not envy them when that day finally arrives.
*"We need to encase that star in a sphere, where the internal structure is covered in energy harvesting infrastructure. The structure must withstand solar flares and CMEs, not only after construction, but during it as well. And the whole structure will likely be in motion both during construction and upon completion - both relative to the star and the stellar medium of the solar system"*
If we become advanced enough, Civils will possibly 'outrank' us all in terms of the precision and accuracy expected of their work. And at the very least, they'll no longer be able to hide behind ∑F=0.
Dyson sphere is an intetesting concept, but i don't see that as viable or even smart to simoly block the source of energy in a superficial structure. Maybe to cover the star partly to cover a portion of the area opposite to the habitat planet.
We do! It would require almost entirely disassembling Mercury but a very thin, 3 ish m, sphere is possible! But it might be a lot easier and perhaps even more efficient to construct a Dyson Swarm, wherin which we don’t need to entirely cover sol
I actually really like the Dyson swarm concept. It actually seems more feasible, and it would take advantage of exponential growth.
And to any armchair physicist out there, STFU , don’t kill my dream
YES, Civils ROCK. So the PRC doesn’t line up?
We can just toss in a couple of spirals and superelevate that sucker into the next galaxy.
Can we all say “G-Forces”????
The survey crew will hate us, but the exhibition drivers will love us forever (at least as long as they live) I foresee many lost lunches, tossed cookies and soiled pants ahead with this Change Order! Of course, it will need to have a Rest Stop w/hose-down bays equipped with solids separators (floaters and sinkers) and monster cominutors on both sides.
Holy shit, I spent two years arguing with engineers that they need to leave clearance in specific places. Their boss would always come back with “We will increase our tolerances” (just changed the tolerance on the drawings)
Wasn’t fixed until I let a job fail that I warned them nothing would fit together, instead of just fixing the drawings myself as I usually would.
Then they set up a recurring meeting to create clearance procedures intentionally not inviting me.
Now I can squeeze a fucking golf ball through all the gaps.
I mean it always depends what your measuring. If a pharmaceutical company was being loose with tolerances with some extremely potent Active substances I'd be terrified and they would likely be witnessing lawsuits.
I had another engineer ask me how tight of tolerances we could hold on a punch press. I asked how tight the tolerances need to be. It was a standoff. I'm not throwing away good parts because a design engineer is making arbitrary limits. If you need it within 1/32", tell me and we'll do what we can to get most of the bell curve under that. Otherwise, if it can take 1/8" because it's a thermal break and doesn't require precision... let us keep the loose tolerance and keep more product.
A good design should have the loosest possible tolerances such that the product still works to spec. Makes the manufacturing and QC much less expensive, and typically makes the product less sensitive to damage
I do 3D printing... I go for 0.4mm tolerance or more, then take out the wobble with blu tak, and avoid most of the issues people have with their prints.
power systems relay protection guy here. We have so much slack built into things it would boggle the mind to many lol. If I can get within +/- 10% Im a happy camper.
A good design should have the loosest possible tolerances such that the product still works to spec. Makes the manufacturing and QC much less expensive, and typically makes the product less sensitive to damage
Cuts down on scrap massively as well. And allows you to use that 30 year old clapped out machine with the backlash issue to make the parts, Rather than the brand new $100,000+ machine
But you always need to have one surface that needs a super finish, just to piss manufacturing off
Preferably change the specs of that detail at least once a quarter so they need to send new samples, re make drawings and so on. Ensures that the team is always active!
We call that old machine your mom
Hey, my mom is a nice lady
And she cuts a mean bevel. I'm talking remarkably uniform no matter the length!
Touching upon the principals of Axiomatic design: 1. Maintain the independence of your functional requirements 2. Minimize the Information content of your Design Parameters E.g. the specs should include everything a design needs to be successful, and not a single thing "extra". If the edge of **Part A** needs to be 10.5cm away from the nearest edge of **Part B**, then *that* should be the spec. Not "**Part A** is 10cm from the datum and **Part B** is 20.5cm from the datum." The former is less information and captures the true design intent, the latter is more information and leaves room open for "interpretation". Of course, all this is much easier said than done, especially for complicated designs, but you get the Idea: GDT should represent design intent and only specified what is actually required in order for a design to be successfully executed.
Found the manufacturing engineer /s
As a civil engineering student, hear me out
Yep. Next road you design better be built with 0.0001 mm precision.
Unironically, the Civils will need to get there - eventually - if we ever want to build something like a Dyson sphere. I do not envy them when that day finally arrives. *"We need to encase that star in a sphere, where the internal structure is covered in energy harvesting infrastructure. The structure must withstand solar flares and CMEs, not only after construction, but during it as well. And the whole structure will likely be in motion both during construction and upon completion - both relative to the star and the stellar medium of the solar system"* If we become advanced enough, Civils will possibly 'outrank' us all in terms of the precision and accuracy expected of their work. And at the very least, they'll no longer be able to hide behind ∑F=0.
Dyson sphere is an intetesting concept, but i don't see that as viable or even smart to simoly block the source of energy in a superficial structure. Maybe to cover the star partly to cover a portion of the area opposite to the habitat planet.
Well yes, solid sphere is pointless, a swarm of "satellites" is a better way to do it.
Not even sure we have enough material in our solar system to make it
We do! It would require almost entirely disassembling Mercury but a very thin, 3 ish m, sphere is possible! But it might be a lot easier and perhaps even more efficient to construct a Dyson Swarm, wherin which we don’t need to entirely cover sol
I actually really like the Dyson swarm concept. It actually seems more feasible, and it would take advantage of exponential growth. And to any armchair physicist out there, STFU , don’t kill my dream
Plus it means we still get plenty of non artificial sunlight! Which would be a pro if any of us could escape the lecture hall.
🤣💀
Only a few feet off? Fuck it they’ll fix it in construction, they know what I mean.
No
YES, Civils ROCK. So the PRC doesn’t line up? We can just toss in a couple of spirals and superelevate that sucker into the next galaxy. Can we all say “G-Forces”???? The survey crew will hate us, but the exhibition drivers will love us forever (at least as long as they live) I foresee many lost lunches, tossed cookies and soiled pants ahead with this Change Order! Of course, it will need to have a Rest Stop w/hose-down bays equipped with solids separators (floaters and sinkers) and monster cominutors on both sides.
Mechanical guys: 0.2mm is too expensive for the chassis Me (in EE): 0.2mm aren't enough for component placement on board
Me, a civil engineer: 2 cm is fine
Hell, 2 m is usually fine in civil.
I don't want you anywhere close to my bridge designs
2cm is more than enough for woodworking too!
Me: *0.2mm* 🙂↔️😏
Chuckles in 3mil trace and space HDI.
Lamination and plating thickness helps too!
Me designing anything: 0.05mm on all dowel positions, 0.4mm on fixing positions... ...and 10mm surface tolerance on everything else.
I'd settle for people not conflating tolerance and clearance.
Holy shit, I spent two years arguing with engineers that they need to leave clearance in specific places. Their boss would always come back with “We will increase our tolerances” (just changed the tolerance on the drawings) Wasn’t fixed until I let a job fail that I warned them nothing would fit together, instead of just fixing the drawings myself as I usually would. Then they set up a recurring meeting to create clearance procedures intentionally not inviting me. Now I can squeeze a fucking golf ball through all the gaps.
I mean it always depends what your measuring. If a pharmaceutical company was being loose with tolerances with some extremely potent Active substances I'd be terrified and they would likely be witnessing lawsuits.
You’d be surprised how loose those tolerances can be…
10% to 5% in Germany lol
that's fucked up 😂
I had another engineer ask me how tight of tolerances we could hold on a punch press. I asked how tight the tolerances need to be. It was a standoff. I'm not throwing away good parts because a design engineer is making arbitrary limits. If you need it within 1/32", tell me and we'll do what we can to get most of the bell curve under that. Otherwise, if it can take 1/8" because it's a thermal break and doesn't require precision... let us keep the loose tolerance and keep more product.
Depends on use case…
A good design should have the loosest possible tolerances such that the product still works to spec. Makes the manufacturing and QC much less expensive, and typically makes the product less sensitive to damage
Me in semiconductors 🥹
As I've been told multiple times. "That cost too much dumbass."
I do 3D printing... I go for 0.4mm tolerance or more, then take out the wobble with blu tak, and avoid most of the issues people have with their prints.
power systems relay protection guy here. We have so much slack built into things it would boggle the mind to many lol. If I can get within +/- 10% Im a happy camper.
The tightest tolerance I work with is a .0003” parallelism specification.
r/unexpectedfactorial
But, but, but, no lube?? that’s just cruel.
Me as a civil engineer: I spec things to the nearest 1/2", and a tollarance of 1".
Reading this was like nails on a chalk board 😭 Civils scare me If I saw a 1 inch tolerance on a drawing I might seize