Calling us backwards because we didn't want to spend so much money and resources to "be like everyone else" is a bit harsh.
And I remember growing up in the '70s and the push to convert and the resistance it received. I learned metric in school, and I never did fully memorize all the english measurements (I know a pint is less than a gallon, but not the ratio).
The solution: If we want to have progress, the government only needs to:
1) require gas be sold in metric (and hopefully in cost units available in the US, no more 9/10's of a penny).
2) require work done on gov't contracts be in metric
3) require schools to stop teaching English measurements.
Soon we'll have critical mass and this problem will just fade away on its own.
Hi, btwolfe. Many US companies already use metric units because the export markets demand them. So some tooling changes have already occured. We'll pay the cost at some time, so I agree, why not now? I doubt the change would seem as disruptive as some people think.
Hi, CPDick. I'm in the same position. My mini-lathe and milling machine have inch graduations but I could retrofit them with digital scales and use English or metric units. When my son and I finished a basement room we used a metric ruler because it was easier to give dimensions in centimeters; 37.6 cm vs "18 and 3/4 and a bit." Stanley makes a nice 8-meter retractable ruler (33-428) that includes inch and foot markings. Of course we had to use the inch scale to lay out studs on 16-inch centers.
It sounds like there are really only two countries that are not on the metric standard: USA and England/UK. The only argument for not switching is that it would be too difficult/costly. Difficult because we'd have to learn a new system. Costly because of the retooling costs. I think neither of these arguments are valid. One says that we are not smart enough to adapt, which is just not true. The other assumes the initial cost of changing (e.g., retooling) is the only cost to consider. How about the fact that metric fasteners cost more in the US because they are not as plentiful as english unit fasteners. That's a cost that hits me every day. So in that case, switching to metric would flip the demand (in theory) and there would probably be a better variety of fasteners as well. Moreover, I wouldn't have to pull out my calculator to figure out what 7/64ths drill bit is in decimal.
Bottom line, the metric system isn't that hard to learn and the cost is a one-time expense. The benefit is that we conform with the vast majority of society which may not improve the average American's life, but will definitely simplify mfg and design for engineers.
My metric screw gauge includes both fine and course threads. so it's easy to tell one from the other--when I have the gauge handy. Otherwise, not so. I visited my in-laws recently to replace an outdoor lamp fixture. I needed longer screws to hold it in place and used a screw gauge in a home-supply store and one of the screws for the new fixture to identify the thread size. The gauge showed a perfect fit in one of the threaded metric gauge holes, although it looked like a 6-32 screw to me. The screw would not go into the 6-32 hole, though. Turns out the screw WAS a 6-32. Someone had bunged up the gauge. Well, another trip to the store.
I agree, Mydesign. As others have commented, though, some metric standards can cause confusion and a later comment noted metric "standards" for O-rings have problems. I never knew so many O-ring diameters and sizes existed. I wonder if there is a way to also note the O-ring materials.
I can easily accomodate Metric measurements, I use both daily. I'm not satisfied with the Metric fastener standards at all. I see very little difference between metric 'coarse' and 'fine' threads, those words are ambiguous. English fasteners that have threads that mate (ie not wood screws) are specified by size, threads per inch, and length. 6-32 by 1" tells the whole story, thanks. BTW, the standard for Printed Circuit Board design remains in "mils" which is .001". Almost all designs convert to this standard before release to manufacture, even if the parts are specified as "metric"
Saying move to metric does not solve the lack of metric standards being used in industry in other countries.
There can be 4 different pitches for several thread diameters, different hex sizes for the same bolt diameter and nut depending on the country of origin. Several of the metric fastener diameters require a pitch gauge to tell the difference between coarse and fine thread. The difference between coarse and fine thread in metric fasteners does not equal inch fasteners when looking at maximum pull capacity. In a product where fasteners are used in tension the choice of thread pitch can have a significant effect on space and cost of manufacture. NC and NF inch fasteners are enough different that you seldom use the wrong nut on the bolt.
Metric o-rings need an international standard today. If you tried to stock every possible metric o-ring it would require over 2,000 different part numbers. The difference in diameter on some of the o-rings is so close it is difficult to measure and there is not a good reference for groove measuring information. So when you work on a metric hydraulic cylinder it can take substantially longer to order the seals than an inch size cylinder. Metric rod and piston seals are even less standardized between countries.
Several manufactures cannot even use the SI standard for pressure. Bar and kg/cm is a common term used for pressure not Pascal, the SI unit.
Try buying metric steel at the same price per pound as inch size here in the states. We as a small manufacture continue to adopt metric as quickly as affordable.
The superiority of the decimal system over fractions was obvious to me as a high school student well over 50 years ago, and it still is! Anyone who can't see that must not do any calculations beyond addition and subtraction.
Yes, I too have lots of measuring and machine tools that were made and calibrated to non-metric standards, but that is mosly due to the lack of intelligent leadership in the past. Fortunately the increasingly affordable electronic measuring tools can be changed with the press of a button, so the final changeover would be less costly than in the past.
All we need is intelligent leadership to do it! OK, where do we find some intelligent leadership?
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