Feet-Inches-Eighths to mm

May be you should tell these guys too:

https://www.conversion-metric.org/length/decameter-to-meter

https://www.unitjuggler.com/convert-length-from-dam-to-m.html

they mix and match too...

Appears to be an American spelling thing!....since the conversion tables are more about Imperial (US) units to SI, one suspects this is the source of the dm or dam unit, as Americans interchange the abbreviation:

https://en.wikipedia.org/wiki/Decametre

 

AH Daiquri so you don't use oncia or Piede


You could try working in Railway modelling converting "chains" into 4mm to the foot Scale.

I remember reciting the lengths of Rods, Poles or Perches at primary School. It was a bit of a shock to get to Seconadry school to find almost everything was in Metric!!

 

That's the proverbial German precision.
I have sent an e-mail to the guy, telling him about this error and this discussion.
Cheers

 

I work with some old boat offset table. Of course I use excel for conversion. But if you need to convert just some values - better to do it on the web. Actually input offset table in feets and inches was more easy - less digits.

 

Never heard of them - oncia et al.

Ahh...we must be similar age then. During my O-level geography I recall the maps were feet when I started and the next year all were in metric...very confusing at that age!!!

 

Wretched old Imperial stuff - including Double Elephant drawing paper sizes....
Yes I can remember learning all the chain, furlong, perches stuff, even doing some tech drawings in inches....'til the class got halted for no specific reason - likely - no one needs to make things anymore syndrome. Strangely I don't find it hard to envisage lengths in inch(es) and fractions, but decimal inches always seem a little more elusive.

Fortunately the SI system is a bit more sympathetic on the whole. Funny how 0.39701 sticks in the grey cells....
Having got used to CAD which accepts Imperial input when working in metric you get lazy!

I suppose most of the maps of the World I had as a child were still showing lots of pink...
As it happens I have an 1896 Times Atlas with 'Unexplored' Polar regions on it!. It does seem quite strange with all the extra information we have since then.

 

SukiSolo you dropped a three in the "things that stick in ones mind" proposition. Me too SS I have several numbers imprinted in my noggin that converts one system to the other. Grams, milliliters, yards/meters and all that stuff.

The number I am pretty sure you intended, is 0.0393701, the number of thousandths of an inch that is equivalent to a millimeter...... 39.3701inches in one meter divided by 12 inches in a foot= 3.280 feet per meter and so on...... .

Americans have rightly been accused of being Insular. In the case of metrification, we stand guilty as charged. We are being punished accordingly.

 

Yes, Excel is the way to go. Its so easy to lay the offsets into an Excel worksheet, and calculate the metric equivalent, why would you use some kind of application ??

 

Oncia and Piede are old italian equivalents of inches and feet. But each of the many old Italian states had different measurement systems. So with their unification it made sense to go metric, they were one of the early adopters of the metric system in 1861.

I remember many of the maps showed pink round the world even though they were in some cases already independant.

Below an inch I almost always work in millimetres (25.4mm to the inch)
Below a foot I mostly work in Inches, unless I'm working on the model railway then it's 4mm to the foot.
Above a foot I almost always work in inches feet and yards.

For money I work in pounds and new pence, if I convert modern prices into Lsd then I realise how much prices have gone up since 1971 and it gets too frightening...

 

Close, but I understand, having worked with plenty of UK toolmakers who work in thou' but I use mm and hundreds and thousandsths of mm too. You just get used to instant mental calcs to talk with the toolmaking guys....yeah, 4 thou = 0.1mm just quick ROT...just interference fits on bearings and stuff gets down to really pretty fine tolerances.

Having done some railway carriage design work, at least the old British Rail drawings from circa 1980 onwards were all metric!. Also had to do mm to inch conversions for US clients....easy with a mouse click!. GM and Ford went metric circa 1978/9 because they realised they were building Global vehicles, even Reagan could not stop them!.

Pity the main metric units were 'wrong'. I believe a nautical mile was meant to be 1Km but they got the circumference of the earth wrong.... In other ways such as density etc it makes things much simpler.

For The Q, I will say farthings were not legal tender when I was born.....

 

Ah the Farthing, one 960th of a pound, Sadly I was alive then and still remember them. first known to be produced around 1216, although they stopped manufacture in 1954 and they ceased to be legal tender in 1960 although I remember sweet shops still taking them some time after, chews, were a farthing each or 5 for a penny.

In todays purchasing power the old farthing would be worth about 2p due to inflation when it was withdrawn, which means our current 1 new penny can't be long for this world, what will the 99p shops do?

 

Nothing smaller than 5c in Australia, and it is not uncommon to see one lying on the ground, days after someone dropped it on the footpath. Not worth bending down to pick up !

 

goods.
I try to attach evolution.

 

A good effort, but its easier often to simply import the whole table of offsets from a PDF of the plan, and have the print out next to where you are lofting the panels.

Even easier is to convert the figures to a line drawing in a dxf file using a Cad package, and get the co-ordinates cut by CNC, if its a big enough job.

 

I use decimal inches.
Measuring tapes with decimal inches are readily available, and it is easy to estimate 0.01 inches.
So one can think in American units (e.g. a plywood sheet is 48 inches wide), cut a sheet with a Festool saw blade 0.1 inches thick, and make further measurements with the same ease as in any other decimal system.