Question about metric 6

[murdof]

Hi guys,

we are a company (ACE-Hellas SA) that has a software for static and dynamic analysis plus design of structures.

The question though is the following:

Currently we are looking for partners to promote our software all over the world.
Our software supports only metric and not imperial units.
I see that in US there are a lot of talks about adopting officially the metric system.
For us to support imperial units is not so easy - as we have to recreate all forms and calculations, so it will take a lot of time.

Do engineers in US work with metric or imperial units for the static and dynamic analysis?

We want to see if we should try to promote the software in the US as well.

Thanks!

 

[LittleInch]

The worst aspect by far as mentioned above somewhere is when nominal measurements are then converted exactly into the other unit (seems to be more imperial to metric), hence 1" becomes 25.4 instead of 25 or 30. Drive me mad every time I see a very precise number for something I know is a nominal figure and if I convert it back you can see it's just 6 foot or something like that. Not that the US will ever change IMO, but if it does by small degree, this is a key point to watch out for. Lots of people I know still use imperial for timber (2 x 4, 3 x 3 etc, even though what they are buying is actually 50 x 100 and 75 x 75...) Ok for building, but not precise drawings..

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[hokie66]

But Little Inch, a 2 x 4 is not that size either, it is just lingo.

In countries like Australia, where the SI system has been in place for many years, soft conversions are uncommon. We don't have 8' or 9' ceilings, they are 2400 or 2700. And the walls are built with 70 x 35, 90 x 45, etc. studs.

 

[moltenmetal]

Sorry to be an @ss here, but the US do not use Imperial units- they use US customary units. Their gallon is smaller (3.785 L) than the Imperial gallon (4.54 L, such that 1 imperial gallon of water weighs and even 10 pounds- at least making some tiny bit of sense). Any useful piece of engineering software is going to have a unit conversion system on there, and will need it for a long time.

In Canada the transition to SI is anything but total, despite happening forty years ago. Sure, all the official weights and measures stuff is in metric, and people talk about km/hr and km distances rather than miles, temperatures are in degrees C, milk comes in litres etc. But we share so much across the border that we still work in all three systems- US customary, Imperial and SI/metric units. Plywood is still sold in the store by its inch dimensions even though it's made to even mm thicknesses. Pipe here is all inch NPS dimensions, and tubing in OD inch dimensions. And nobody uses metric fasteners, other than in automotive- they're still in the specialty part of the hardware store, in the tiny little bins with an enormous cost per item.

Fortunately, Bob Villa seems to have taught the Americans the virtues of the Robertson (square drive) woodscrew, but that's about all we can claim to have spread from our side of the border! In years past, I had to send a set of Robertson screwdrivers with each plant we built because as much as we tried to have "bisexual" fasteners everywhere with at least a slot to resort to in a pinch, some Robertson-only screws would sneak onto the plant somewhere and we'd have a hell of a time on site with them. Now you can find square drive screwdrivers in any Home Depot south of the border.

 

[TomDOT]

LittleInch - I fight that translation over-precision in ASTM all the time. My favorite was "Approximately 1 pint (473.18mL) of gravel (250-300 stones.)"

Each stone is ~1-2ml, yet they went the extra distance to require precision to the hundredth of a ml.

 

[LittleInch]

A 2 x 4 was a 2 inch by 4 inch, but is now something marginally different. I couldn't believe someone would actually cut down a piece of 4' x 8' plywood to the exact 1200 x 2400 though - that's really crazy. The UK went metric officially in the early 1970's, but managed to keep miles and mph and pints in official weights and measures, but precious little else. However fuel consumption in cars is still spoken of in mpg, despite it being impossible to buy a gallon of anything for about 25 years...

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[loki3000]

It seems ironic to me that mainland Europe, including France, commonly uses such peculiar units as kgf/cm^2 for stress, but the countries following the UK tradition use "proper" SI units as a matter of course.
no we don't. the default unit for stress is MPa everywhere i know. prehaps the british are doing it differently.
there are some other units in use sometimes, like BTU, but i am not aware how much (outside britain).