Thread: Imperial vs Metric system

I'm in a quandary, I've discovered a paradox which may well lead to the break down of my measuring system.

I'm roughly 1.8 stus tall........ how can that be?

Stuart

Originally Posted by _fly_

But if you say 1.375 inches.
An american is going to ask you what the hell it means??

Even after explaining what it means they still get stuck,
they want it as 1 3/8 inch.

So does an American Micrometer have only fractions on it? I have seen verniers like this.

Dean

I like metric, but having grown up with both, I tend to "think" in imperial I think milk still comes in pints and miles per gallon still means something more than liters per 100 kilometers... I'd grab a 1/4" drill rather than a 6mm drill.

I like this video... non believers can start watching from 8:42



Slightly further off topic, but hands up if you remember this.... they flogged the song endlessly on our local radio...



Regards
Ray

Originally Posted by Bedford

Attachment 294469

Hi

Does that white tape have a brand name?

I'm not sure as it's not mine.

Originally Posted by _fly_

Is the white one a radius tape?

What's a radius tape?

Originally Posted by Techo1

What's a radius tape?

Wrap it around a circumference and it will give you the radius of the circle with vernier accuracy. Keith Fenner uses them a bit.

Dean

Originally Posted by Techo1

What's a radius tape?

Pi tape- Diameter Tape, Precision Diameter Tape by Pi Tape Corporation, the original manufacturer of Pi Tape brand precision measuring tape, outside diameter, linear, Go/No-Go, inside diameter, O-rings, exteneded range tapes, Pipeline diameter measurement and

Originally Posted by Bedford

No, it's a five dollar one from the two dollar shop.

The white one has ten eighths!

Does it have 12 inches to the foot? If it has 10 it could be in Cape feet as it has 10 inches and although the foot is not the imperial foot the conversion goes to about 5 decimals.
Regards

Ye olde length gauges at Greenwich Observatory

Originally Posted by snowyskiesau

I was wondering if they still did the multiplication tables up to 12.
Once there was a reason for it but not since 1966.

They don't seem to put as much emphasis on teaching any tables as I would like them to these days. The teachers seem to pretty much leave it up to the parents to teach the kids tables. When I went to school, every morning started with tables.

We went to Decimal Currency in 1966. That in its self was right up there with the imperial system if you think about it. The 14th of February 1966. Niether the start nor end of the financial year or the calander year. Not Australia day... Valentines day!!!... Go Figure.

We actualy went to the metric measuring system in the 70's, some 10 years after decimal currency. I think it was about 1976, but I don't remember the actual date.

You have to admire the simplicity of the metric system, & the way it flows across the board. EG., A Lt of water weighs 1kg.

The US Military use metric for distance, but they still seem to use pounds for weight.

And I must admit, that MPG had a lot more meaning to me than Lt/100 for a long time, but these days I tend to talk in Lt/100.

Does anyone know the standard length of a White line marking the centre of the road? It used to be 12 feet.


Steve

Knots R still used for navigation at sea because they match the circular compass 360 degrees (1 nautical mile = 1/60th of a degree).

The problems with distances... on charts is that you can ONLY use the Lattitude (distance N or S from the equator) or the side scale on the chart for plotting your distance... because longitudinal distances converge toward the poles.

TVMDC [True Virgins Make Dull Companions] or more correctly True, Variation, Magnetic, Deviation, Course, 'to steer' (The mariners aid memoir) being how one converts magnetic (compass) bearings to true for chart use or vice versa.

This base 12 calculation stuff seems to give "the wee kiddies" (those born after the 70's) all sorts of gypper at the navigation classes - they are fine as long as the GPS works - but seemingly screwed when it doesn't!.

Wasn't it only yesterday some pilot and navigator landed their dream lifter jumbo jet at a small municipal airport 13 km's away from their correct landing strip?

GPS error.... cough cough...

Funny but when I bought my 1st GPS the packaging clearly said words to the effect "only to be used for secondary navigation" (i.e. as a backup to manual nav) and never to be used as a primary source of navigation) yet today we have car GPS navigators etc and EVERYONE just trusts them.

Thankfully the yanks quit dithering the GPS signals some years back... increasing accuracy somewhat.

That said in Gulf War 1 - I was offshore when the first strike started..... went out and followed a GPS track.... but when we tried to follow it back.. the war had commenced and the seppos screwed with their GPS satellites data - had we followed our GPS (and not the compass) wed have run out of fuel somewhere near antarctica.

Then I was myself undergoing nav training on the day after 9/11 and happened to have my hand held GPS with me in Perth at the nav school.

I had been fishing approx 600 km's south of Perth and saved waypoints of some honey holes - as well as up at shark bay and saved waypoints.

On 9/12/2001 - when I entered a 'go to' on the GPS for the way points south of Perth - it pointed me NORTH, and when I entered "go to" for the way points north of Perth at Shark Bay it told me to go south, (it had a built in electronic fluxgate compass which seemed to go nutso).

For ME - GPS will always remain a backup form of navigation.

On trips offshore to places like the Houtman Abrolhos Islands (54Nm out of Geraldton) while I have and use a GPS chart plotter - I still carry paper charts with courses and back bearings all plotted manually - before leaving. The vessel has a chart table and chart lights, chart tube and carry's parallel rules, dividers & a pad and Russian space biros just in case. The compass is even aligned every 3 years by a compass aligner to give me my deviation tables. Might not need it often but the day I do its all there along with the knowledge of how to use it.

I consider those of us born in the imperial age who have converted to metric to have an advantage of those younger with only experience of one system of measurement.

These blokes seemed to have managed alright without metrics or a GPS Chart plotter...



I'd like to become conversant next with a sextant just for the heck of it!.

My Tuppence.

Originally Posted by _fly_

Does anyone else remember when Current Affair tried the april fool joke that soon we would go to decimal time.
100 seconds, 100 minutes and 20 hours per day.

In more naive times, before radio was populated with angry little men - probably the early 70s during the introduction - a bloke who used to feature a sparrow on his morning show, did pull that stunt....and remarkably effectively, lots of red faces that day.

Originally Posted by Timless Timber

Wasn't it only yesterday some pilot and navigator landed their dream lifter jumbo jet at a small municipal airport 13 km's away from their correct landing strip?

GPS error.... cough cough...

I'd wager, the exact opposite, visual approach, target fixation and disregard to any instrumentation. There were cases here of large jets lining up with under construction runways in the NDB/VOR era and probably before that using radio range.

Last year or the year before, a large US military transport did land at a small GA airport adjacent to the military base with similar runway alignments, pity for them, a senior general was on board.

Originally Posted by A Duke

Does it have 12 inches to the foot? If it has 10 it could be in Cape feet as it has 10 inches and although the foot is not the imperial foot the conversion goes to about 5 decimals.
Regards

The tape is at my dads, I'll try to get hold of it during the week and get some more info.

I'm pretty confident it's just a dud from China though.