#10 screw and 3/16 screw

[WhatTheFlux!]

Hating on the French is soooooo 10 years ago. Get with the times man.

[Shade]

The best reason NOT to use the Metric system... it's French...

[WhatTheFlux!]

"Uh this machine is set to metric, how do I set it back."

"You can't it's Canadian."

"Ok, so what's 310 in F then?"

"Hot enough to melt nylon."

"...Yeah but I need to know what it is in F."

"No you don't. Just go with it."

"And what the hell is BAR? And everything is in MM. I can't run this."

"We've run it for three years without issue, maybe the problem is you?"

"No the problem is the machine uses non-standard measurments that I don't understand and I'm not about to learn. THIS IS AMERICA the rest of the world should be using our measurment system... not some system invented in France. What the **** is wrong with that picture? That's right, FRANCE. I REFUSE to use anything produced by the French or invented by the French."

"Ok... you're fired. Plain and simple. No one else had a problem with this, and on top of that while I have no great love of France or French culture we do have French and French-Canadian customers. Can't have you badmouthing the folks who pay us."


----
This happened about six weeks ago. His attitude changed real quick, started backpeddling real fast when I threatened him. Now he's "down" with metric.

I never had any issue switching from one to the other, and I can think in metric just fine. Never had a issue. Only time problems cropped up for me was during conversion. That's when I decided to just think in metric for those applications rather than screw around with numbers.

[DATo]

The switch from Inch to Number measuring for "small" threads produced some
wierdcases. These are generally threads less than 1/4"
In Number Screw sizes, You start with .060 as a base and it is a 0-80 thread, or 0-72 etc.
( Please note that .0625 is 1/16 , so " )" is close to that fraction benchmark)
Each sequential thread size grows by .013" and gains one digit.
A 1-72 for example is .073" and a 2-56 is .086 in the "Major Diameter" measurement.
A 10-32 is .060 PLUS .130 ( 10 x .013) or .190
Your old 3/16 thread is .1875"
The only "exact" one is 1/8-40 (ie.) as it meets a 5-40 (.060+.065) at .125 dead on.

Real confusion is with the #14 threads (.060 + .182) as its .242
So if you have a 1/4 -20 bolt, it will not fit a 14-20 hole !

Old machines and hardware still use the old standard of 100 ago

Its a lot easier, to refer to numbers than fractions.
Can you imagine doing a 5/64-72 or a similar ?
It was an attemp to make the range smaller than 1/64's
Of course it doesn't get a simpler than Metric..but I won't go there

Rich

Excellent post Rich !

Don't mean to nitpick but I just wanted to mention that the number series screws actually start with "quad-aught" 160's (0000-160) which have a major diameter of only .021" dia. The smallest I have ever seen are triple aught 120's with an O.D. of .034" and we actually have them as well as the taps in our shop. I can no longer see the threads without a magnifying glass. To be honest I can't remember the last time we used them though but we have used them - it's been probably literally decades ago as near as I can recall.

[Paul Alciatore]

Just to add a bit of interest to our lives...the tapped holes in those aluminum 19" server/relay/telecom racks full of high tech equipment are usually#12-24.

Only the computer nerds and the telephone people are stupid enough to use racks with 12-24 holes. The radio and TV industry uses 10-32. I have bought dozens of the racks and thousands of the screws. Always 10-32.

[dfw5914]

If not, then why not?

[dfw5914]

...Metric threads are 55 degrees with rounded roots, yes?

[dfw5914]

Ssshhh Tim,
Don't let on that old Joseph who set the first standards up before American was even found and used 55 degrees with rounded roots and flanks is still the strongest thread form to date.

.

...and why metric threads are 55 degrees with rounded roots.

[dfw5914]

...and why yellow is clearly superior to orange.

[Juergenwt]

Those " Imperial People" will fight on till death along with their friends in Liberia and Myanmar. They don't understand that the Metric train left the station long, long ago. They will keep on selling inch/pound/gallon/ Fahrenheit products as long as they find a buyer. After all - the horse and buggy worked just fine. Why change it. And the US used to be the leader! Right? All of this because we had a President (Regan) who was still in the age of the "Charge of the light brigade" and a Government unable to look past the next election. In the mean time the country suffers. Cans of food that give the weight in ounces and the ingredients in grams. Children unable to do math because the have to jump from metric to imperial. Industry fighting a running battle with product for sale in metric and engineers mired in the imperial system. Travelers being called stupid because they don't know how far 1 Km is. The list goes on and on. The next time you buy 325 mg aspirin pls tell me how much in imperial? If you have a 12 oz can of beer - how many in a barrel? But on and on they go fighting for the "Foot". And talking about a "foot" - why is it even called Football? That is just plain dumb! May be we should call it "Carry Ball" or American Rugby.

[Juergenwt]

No. One standard with fine and course pitch. Metric has fine and course as well. Metric and imperial both also offer "special" threads but that's just stupid in most cases and we won't go there. No advantage of one over the other. The problem is that switching to metric takes tons of cash for tooling, so demanding that the manufacturing behemoth the US once was to change to metric because some French wussy, bottle-glasses Beaker scientist could then just move the decimal instead of having to remember a conversion factor just wasn't going to happen.



Yea and over here he'll bring you a 1/2-13. If you want fine pitch, then you'll have to send him back a second time.

I don't see why anyone thinks there's such an advantage to metric. The metric bolt notation even looks clumsy to me. Ever screw up and read 1.25 to be 1.75 for a pitch and vise-versa? That's the problem with metric. You want to be lazy and just move a decimal place? Fine. Now you have decimals in everything because you aren't allowed to just divide something up anymore. Especially if it's thirds or something. Oh God - Blasphemy! 1/3rd of a centimeter? Unheard of! Why? (I think the American engineers picked 13 for the pitch of a 1/2" bolt just as a jab to the metric fans. "1/13 of an inch? Is that even allowed?" hehe.)
I think people who love metric are the same type who hate fractions or something. US units are good for learning fractions. Units are supposed to be something divided up to begin with right? Whomever limited the divisions to only 10 was just short-sighted. Why not be able to divide something into whatever unit is the most useful instead of arbitrarily picking 10? THAT'S right - I called metric "arbitrary" and I meant it.

If a guy is not good with numbers, he's not going to be much good in either system. He'll be able to blame the "other" system though, so he's got that going for him.

The world will NEVER settle on a single standard I don't think. Unless metric could include the two most universal units in the universe, it will never take off. I'm speaking, of course, about the units of HH and FF. These are used more than any other unit in history and their intuitive relationship to all things is apparently undeniable. It's the newscasters' standard measure and the abbreviations of course stand for Human Hair and Football Field.

This silly "metric system" thing doesn't stand a chance.

"takes tons of cash" - another guy who does not know what he is talking about. When GM changed to metric they anticipated an enormous amount of money to be spent on the conversion. They ask the government for tax relieve for all the money spent to convert to metric. 1.they
found out it cost less than 1% of what they had estimated and by the third year they dropped all claims for tax relieve because the savings from going metric far exceeded the cost.
Look here: http://lamar.colostate.edu/~hillger/pays-off.html#gm

[Juergenwt]

when you go to the hardware store, anybody worth a damn will know to ask you "coarse or fine thread pitch?" when you ask for that 1/2" bolt...

You just ask for M12 - Period! Only in metric challenged US will they ask for the pitch. If for some ungodly reason you need a "Fine Pitch" -ask for it!

[Juergenwt]

John,
Here in the Simple US, it's always the specials...

The biggest problem I run into here, is a lot of the US Metric Bolt heads are 1 mm bigger than EU metric bolts...

Fun In tight spaces.. EU is used to that, I'm sure

61.1 Million Brits ought to be able to tell Us 300 million plus, to get it right

More BS!

[Juergenwt]

You don't know what you are talking about. Sorry!

[andywander]

Just to add a bit of interest to our lives...the tapped holes in those aluminum 19" server/relay/telecom racks full of high tech equipment are usually#12-24.

well, some of them are.....many are also 10-32.