metric drill set explained?

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liveaboard
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Re: metric drill set explained?

Post by liveaboard » Fri Oct 05, 2018 4:27 am

In Europe and other places I've worked, fine metric pitch fasteners are hard to find; and rarely used.
The common metric pitch ones fall between the SAE fine and coarse threads, a sort of medium thread I suppose. Of coarse there are several grades for tensile strength. I've never seen a metric fastener with coarser than standard thread.
On the rare occasion I do need a bolt with a different thread pitch, even in Europe it has to be ordered from a specialist supplier.
Or made on the lathe.

Mr Ron
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Re: metric drill set explained?

Post by Mr Ron » Fri Oct 05, 2018 3:55 pm

This discussion seems to have drifted from metric drill sets to metric vs imperial fasteners. What it all boils down to is; preference. I am open minded, but to say one system is superior to the other is ridiculous. Both systems have been in use for hundreds of years and during that time (remember the industrial revolution) all the great inventions that have made our lives easy. Whether metric or imperial, the end result has been a positive achievement. There are some who are just prejudiced against one system over the other. These people should lighten up. They say the metric system is easier to understand, and that may be true if you were brought up with metrics all your life. Those who embrace the imperial system grew up under the imperial system and to them (me included), it suits us perfectly. I don't, won't declare one system is better than the other. Like many on this forum, I say "you will take my imperial measurement tools out of my cold, sweaty hands after I'm dead". There's just too much hullabaloo going on.

Note: This was the first time I have ever used the word "hullabaloo" and spelled it correctly the first time; thanks to a solid English language education. Please don't take this statement as a new controversy in the making; merely a statement.
Mr.Ron from South Mississippi

TRX
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Post by TRX » Fri Oct 05, 2018 11:22 pm

Mr Ron wrote:
Fri Oct 05, 2018 3:55 pm
This discussion seems to have drifted from metric drill sets to metric vs imperial fasteners.
Internet threads tend to do that...

"Hey Rocky, watch me pull a rabbit out of my ha - " [rrAARRR]

Metric threads are an abomination. Apparently as long as they're dimensioned in metric units, they're "standard." Which is why it's not even worth sorting my metric fasteners beyond diameter.

Anyone who did much foreign car work "back in the day" will remember that Japanese car, Italian car, German car, and "hardware store" metric threads had minimal overlap.

For extra points, the Germans loved them some 55 degree metric threads...

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WesHowe
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Re: metric drill set explained?

Post by WesHowe » Sat Oct 06, 2018 10:39 am

John Hasler wrote:
Thu Oct 04, 2018 11:49 am
"SI" does come from the French: Système international (d'unités). The French invented the metric system, after all, and the BIPM is in France.
And the U.S. was one of the original signatories. Metric was a great step, even if we don't directly use it here. Our "inch" has been standardized as 25.4 mm. Thus there can be direct traceability to the International Standard. There were side effects from this definition change such that the references for the entire surveying system in the U.S. was changed in 1983 (NAD 83) from the ones established in 1927 (NAD 27). Small differences (2 ppm) add up over large distances.

It might be interesting to note that the Metric Conversion Act of 1975 made metric the "preferred" system in the U.S. Some 43 years later about all you see changed is that packaged products show both the standard units and the metric equivalent. My personal belief is that the U.S. will never adopt metric in general use until products appear in whole and common fractional (e.g. half) metric units, and that would require some sort of "boot in the a$$" to happen, since units like liter and half-kilo are larger than a quart or a pound... the first company to start packaging that way would have to charge more, placing themselves at a competitive disadvantage. No one volunteers to place their neck in a noose.

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tornitore45
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Re: metric drill set explained?

Post by tornitore45 » Sat Oct 06, 2018 12:44 pm

since units like liter and half-kilo are larger than a quart or a pound
Will we see a 1 liter San Pellegrino Mineral water next to 1 qt Geyser Spring water with the per/floz unit price fro comparison?

It is written in small print but I always compare the unit price when grocery shopping.
Mauro Gaetano
in Austin TX

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WesHowe
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Re: metric drill set explained?

Post by WesHowe » Sat Oct 06, 2018 1:16 pm

tornitore45 wrote:
Sat Oct 06, 2018 12:44 pm
It is written in small print but I always compare the unit price when grocery shopping.
Being smart, and being like everyone else are not the same thing. :)

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