Timeline for Why do so many PCB-designers use non-metric units? [closed]
Current License: CC BY-SA 3.0
24 events
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| Dec 22, 2017 at 17:13 | comment | added | Trevor_G | There is another legacy reason that is not valid any more. 30 years ago if you wanted it made and had your units in metric, the machine shop had to recalculate everything in imperial because the tools available, mills, lathes etc, were all imperial (at least in North America) e.g. One turn of this knob = 1/4 inch etc. Today NC machines, again computerization, make that irrelevant. | |
| Dec 22, 2017 at 17:07 | comment | added | user57037 | In science books such as physics text books, the pound and ounce are force, not mass. Apparently there is some ambiguity over this point, and in practice pounds and ounces are used as mass anyway. The "fluid ounce" is used as a volume measurement. But the word "fluid" may be omitted. I suppose your point that the situation is ambiguous is valid. But in a technical forum such as this, an ounce is a force by default. | |
| Dec 22, 2017 at 17:06 | comment | added | Chu | 12 is far more useful than 10: more factors, can do thirds without a problem, to name but two! | |
| Dec 22, 2017 at 17:04 | review | Reopen votes | |||
| Dec 22, 2017 at 22:36 | |||||
| Dec 22, 2017 at 16:56 | comment | added | Trevor_G | The most basic reason is when we started out DIP packaging was king. As such, everything was on a 0.1" grid. Tools back then were also not computerized. Today you can make your grid and footprints any size you like, but back then things were designed with standard templates and stickers. As such, imperial units became the norm. Time has passed since then, and more metrication has slipped into the design world. But at this point, since everything is computerized, it really does not matter what you type in as a size, the software does the conversions for you. | |
| Dec 22, 2017 at 16:54 | comment | added | 12431234123412341234123 | @ChrisStratton: That is me exact problem: why do we have 2 system when we could only use one? | |
| Dec 22, 2017 at 16:53 | history | edited | Transistor | CC BY-SA 3.0 |
Fixed indeces.
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| Dec 22, 2017 at 16:53 | comment | added | 12431234123412341234123 | @mkeith wikipedia ounce: "The ounce ... is a unit of mass" | |
| Dec 22, 2017 at 16:52 | comment | added | Chris Stratton | This rant is uninformed nonsense. Any decent PCB cad package can be readily switched between units, and any competent PCB designer working in the US market can readily think in both systems, and will typically have to within the same board as its a rare design that does not include components and/or constraints inheriting from both systems. | |
| Dec 22, 2017 at 16:51 | history | edited | 12431234123412341234123 | CC BY-SA 3.0 |
deleted 87 characters in body
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| Dec 22, 2017 at 16:49 | history | edited | Transistor | CC BY-SA 3.0 |
Tidy up.
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| Dec 22, 2017 at 16:49 | comment | added | 12431234123412341234123 | @mkeith not only, it is used for mass, weight or force, volume and thickness. | |
| Dec 22, 2017 at 16:48 | comment | added | Dave Tweed | This is not the place for religious discussions. And you're wrong about one thing: Eagle does use metric units internally. | |
| Dec 22, 2017 at 16:47 | comment | added | Trevor_G | @mkeith "The United States simply has not switched over to metric yet" and probably never will. | |
| Dec 22, 2017 at 16:46 | comment | added | user57037 | The United States simply has not switched over to metric yet. Reference materials refer to the legacy units of AWG, oz copper, traces in mils, etc. But there is nothing stopping you from working in metric. I would also like to point out an error in your question. The ounce is a unit of either volume or weight, not mass. | |
| Dec 22, 2017 at 16:46 | comment | added | Transistor | @mkeith: I can't see anything "ranty" in the question. The tone is quite measured throughout. | |
| Dec 22, 2017 at 16:46 | comment | added | 12431234123412341234123 | @RonBeyer I talk about the internal grid, not the displayed grid. | |
| Dec 22, 2017 at 16:45 | answer | added | Shredder | timeline score: 7 | |
| Dec 22, 2017 at 16:45 | history | closed |
user57037 Dave Tweed |
Not suitable for this site | |
| Dec 22, 2017 at 16:40 | comment | added | Wesley Lee | I quite dislike imperial but use the imperial grid when layouting components with imperial based pitch (2.54mm, 1.27mm, etc) | |
| Dec 22, 2017 at 16:40 | comment | added | user57037 | I'm voting to close this question as off-topic because it is a rant disguised as a question. | |
| Dec 22, 2017 at 16:38 | comment | added | Ron Beyer | You can set the grid in Eagle to use metric units... | |
| Dec 22, 2017 at 16:32 | review | First posts | |||
| Dec 22, 2017 at 16:49 | |||||
| Dec 22, 2017 at 16:30 | history | asked | 12431234123412341234123 | CC BY-SA 3.0 |