Metric system

Docnick

Sorry circuitsmith; I meant to say Telefunken. "Grammophone" has different acceptable spellings, such as Grammophon and Gramophone, according to the New German Dictionnary by Cassels. "Grammophone" is not acceptable. And a Gramophoneplatte is a ....... record.

In another post I related to a summer job I had laying out survey lines for gas pipelines. A surveyor's tape is in feet, with the last foot calibrated in 1/10s of a foot, since surveyors do not use inches.

An old codger got up from hs bench, walked over and asked me: "Hey sonny, it that there one of them tapes with ten inches to the foot?".

bscar2

http://theoatmeal.com/pl/senior_year/science

Mechaniker

The unit of air pressure on mechanical European (German) tire pressure gages is the bar, usually from 0 to 4 bars (≈ 60 psi), in increments of 0.1 bar.

Docnick

Bars make a lot of sense, but some countries use kilopascals. Typically a car might have 225kpa as the factory recommended air pressure.

VDCdriver

"Bars make a lot of sense"

They do, especially at the end of a long, hard day.
However, I prefer to bring my own (Johnny Walker Black), rather than pay inflated drink prices at bars.

That was what you meant--right?

;-))

Mechaniker

Docnick — "Bars make a lot of sense, but some countries use kilopascals.

Bars and kPa are used interchangeably in Europe. 1 bar = 100 kPa. (1 Pascal (Pa) = 1 Newton/meter²)

So the 225 kPa factory recommended air pressure would simply convert to 2.25 bars (or 32.6 psi for the Luddites).

Rod Knox

Any opinions on Witworth?

Docnick

To my knowledge, the Whitworth thread was a British screw thread that was gradually phased out as the industry went metric. It was very popular in the car business there. At that time we had here Unified National Coarse (UNC) and Unified National Fine (UNF). Europe had metric D.I.N., originally from Germany.

Mechaniker

Metric has both coarse and fine thread, plus several grades in between.

For example, there is 14x1.0, 14x1.25, 14x1.5 and 14x2.0.

CapriRacer

There's nothing in either the metric system or the English system that sets limits on things.

Take the bolts and nuts issue brought up above. In the English system, the pitch is specified in "threads per inch". There are standards, but that doesn't preclude anyone from making something off standard. In fact, there are places where an adjustment screw has used an ultra fine thread that isn't part of the standard (as in UNC and UNF).

The same for metric - but in this case they specify the pitch as the distance between threads. There are standard thread pitches, but there is nothing that prevents someone from using an unusual pitch.