METRIC vs IMPERIAL

dynamic
conversion
imperial
units
metric

#1

Hi Everyone,

This topic really applies to SketchUp, SketchUp Pro and Layout…

It relates to half the world using Metric and the other half using Imperial… and it is a simple request both to all users and Trimble .

We know that confusing these measurement units can have castastrophic results [aka Mars Space Missions]… so we need some clarity in SketchUp also.

So Accordingly -

1] Can we all agree that if we publish models - we clearly tag if it is designed in Metric or Imperial Measurements … a simple [m] or [i] would help [even just list country of origin]

2] Can Trimble please publish a simple script / plugin / whatever to convert Imperial to Metric Dynamic Components …

I am sure I am not the only one to have downloaded a component only to find that is in the incorrect units and is a daunting amount of work to convert to the other units.

Now I know people will say they are in real units whichever measure used [metric or imperial], the point here is that a standard door in the USA will not be the same as standard door in Australia etc.etc.

Regards


#2

It’s only the USA + Liberia + Burma (+ to some extent + Canada) that officially use imperial.
At some point they will also adopt the metric system, make life less painful.


#4

#5

It doesn’t matter if it’s time for the entire planet to use metric or not. As far as components uploaded to the 3D Warehouse go, it’s up to the authors to provide them in appropriate dimensions. It would be useful if the authors would add the units used in the title or description of the component. Getting that to happen reliably is probably a losing battle when you consider how hard it is to get authors to upload correctly scaled, clean, properly modeled components.

Perhaps there could be an added auto-filled field in the description area in the 3D Warehouse that reports the model units. At least others could have a better idea of what they are getting before downloading a component.


#6

Isn’t the size of an object independent of the used unit system?


#7

Yes, but people conventionally size things to an exact measurement in the units system they use. 2 inches is awkward in metric, and 20mm is awkward in inches.


#8

When you create a Dynamic component, you will have to choose to use Inches or Centimeters for the internal calculations in your parameters, but if you stick to the default “Use end user’s model units” setting for all the input fields, the unit used shouldn’t really matter much. As Sketchup internally uses Inches to store everything, there really is no great divide between Imperial and Metric. The units displayed are determined by just a couple of clicks in the Model Info>Units dialog, and they can be changed any time.

Anssi


#9

I am from the UK.
I grew up with feet&inches.
At the end of my schooling we learnt the imperial AND the cm&gm system - which didn’t persist!
Then at uni we had got to convert to ‘metric’ - in the UK metres/mm/kg etc.
And in the year I started uni “they” changed all standard construction drawing scales from 1/8":1’ to 1:100 etc.

So… I still think I am 6’1" tall etc.

BUT I can think in both systems…
On site I might say we need 3m of 2x4" - or even 10’ if 50x100mm - the UK only uses ‘cm’ domestically - not in construction !
To confuse matters, surveyors work in metres - so it’s 1.234 NOT 1234

Don’t get me started on pounds-shillings-pence - as teenager we went decimal to pounds-[new-]pence
BUT I can still do the ‘rote’ for the complex mental-calculations for converting pence to shillings and shillings to pounds etc…
e.g.“New coat: £10-19s-6d” is today ~£10.99 - or rounding up £11 !
But the coins were divided in to halfpennies and farthings !
So 1/2d or 1/4d - then 19s-6 1/2d >> ~£1 !
And of course ALL of the coins changed !
At least the USA chose decimal-currency at the offset !!!
Why not metric-measurements ??


#10

Hi Tig, Anssi…

Firstly… Tig, thank you for all the great plugins you have written over the years… truly amazing…

and in my feeble attempts to create / adapt dynamic components my head begins to spin when I encounter a DC created for the imperial world and I want to adapt it to the Metric world… eg a door in Imperial might be 6’8" and yes I can toggle it to mm, but it certainly won’t be 2100mm which is what it woukd be in a metric world. It is very hard to maintain on site credibility if I start scheduling / dimensioning my door heights as 2134mm…

So my point was really, if it was clear it was a Imperial designed component I wouldn’t even both downloading it… unless Trimble had written or documented a conversion technique to do all the hard yakka for us…

My programming skills are marginal now but I suspect it is only a matter of applying some constants into the DC function algorithims?


#11

If you have Pro you can edit a DC.
You can toggle its dimensions between inches and cm.
BUT you can display values in in the user input dialog to mm if desired [I do].
You’ll almost certainly need to reset some base-values or drop-down-list entries to the desired ‘cm’ dimensions.
I find it annoying that if I have a DC set to cm, then still I have to adjust my thinking from cm to mm, but it’s no major pain…


#12

All good points in the reply’s here. But there is ONE thing Trimble could do that would help (eventually). The model info / units dialog contains multiple variations now - why not one more choice that displays BOTH systems with tape measure, dimensions, measures inputs? The only reason I’m ‘stuck’ in imperial units is because I can’t relate to instantaneous conversions in my head. Metric would already be my choice and I could relate to it if I had always seen it displayed somewhere besides the backside of a measuring stick…
(and for now, I will make sure I specify units in anything I get around to uploading!)