Yep,,,, as well as tires are still using “American” rim sizes. I’m guessing they’re that way worldwide?????
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When did metric take over?
- Thread starter Batmanacw
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My friend was describing what he wanted the other day, and said "make it 28 and a half millimeters long". I explained that metric doesn't have halfs. It doesn't, right? 
28.5mm? Nah. It'll never work.....My friend was describing what he wanted the other day, and said "make it 28 and a half millimeters long". I explained that metric doesn't have halfs. It doesn't, right?
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I would bet that if one was to look at the old NASA prints that they are all metric
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and they make inch scales in .1 and .5 and .100 graduations as well, starrett calls them aviations scales. Many drafting scales did as well. So what is your point?
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https://www.newscientist.com/article/dn17350-nasa-criticised-for-sticking-to-imperial-unitsI would bet that if one was to look at the old NASA prints that they are all metric
They finally did but really, where did you even pull that from?
Why not, lot easier to remember that a F or 7 drill is needed. Every set I have has the decimal stamped under the letter/number size. Every manufacture will give a free tap/drill size poster
Yea, if I had a hundred dollars for every time I found someone had or were trying to use 1/8-27 npt in a G(erman)1/8 port?(which is 1/8-28 British Whitworth) If feels good/fine for 3 threads and starts getting stiff due to the thread difference, so people just put a wrench on it an tighten.
They actually make metric fittings/oring ports. Yet the japanse and germans are so invested in british whitworth threads for fluid fittings they won't change. Its hell to find tooling and fittings. Ironically Caterpillar has been changing over to them before all the european and japanese companies.
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I already made my point...twice. Maybe the 31st edition of the ENGLISH HANDBOOK will help.
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But .1", .05" or .01" graduations are not a fractions and easy to divide by 2.
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I worked for a couple German manufacturers as well as with many other equipment manufacturers, the only metric fittings I saw were for the hose to the fitting, the fitting to the equipment was always G or R type fittings, and the R type was maybe 5% of the time. It would be nice if they switched to metric threads so common taps could be used, but I think there is so much equipment out there with the G/R type fittings that it will be slow to be adapted. NPT fittings work close enough in some applications, but if you want any pressure rating, you need the proper fittings and threads. I’ve spent plenty of time tracing leaks that came from the incorrect fittings or threads being used.
I’m surprised you find tooling and fittings difficult to find, McMaster-Carr and Swagelok have plenty of offerings for fittings, and Whitworth tooling doesn’t seem difficult to find. The larger sizes are not as common but I never had an issue getting what I needed for standard pipe sizes.
