Help with imperial measurements

[mtt.tr]

75 feet? You mean 75 inches, presumably?

Read the thread

 

[Mr Fro]

Speak for yourself. 100mm less that a 2x4 @2400 (stud wall size or standard ceiling height) and 6 bags of cement. ( 3 of old)
And yes. I called it a 2x4.

47x94 if you want to be picky.


Oh and 2300mm is over 7 and a half feet.



1982mm metric height of a standard door

2x4? What are you? An American or summink?

4x2 over here please.

 

[eLuSiVeMiTe]

2x4? What are you? An American or summink?

4x2 over here please.

It's 2 X stock
2x2
2x4
2x6
2x8
Doing it the other way around is backwards to me.

 

[tigdlo]

2x4? What are you? An American or summink?

4x2 over here please.

Some of the sales staff at my local builders merchants correct you if said the wrong way round, 50/50 I get it the correct way.

 

[Migmac]

On a golf outing a number of years ago there was a nearest the pin on a par three. Anyhow one lucky shot later my playing partner says that's worth a measure and gets the tape out. Now I forget the actual numbers but he measures it along the lines 2 yards 4 feet and 10 centimeters. And he's a builder.

That sounds about right. I look at the card on comp days and there are all sorts of measurements used.

 

[Bravheart]

That sounds about right. I look at the card on comp days and there are all sorts of measurements used.

It's the nearest that wins at the end of the day not how it was measured

our club brought out a rule that a hole in one wouldn't win because you couldn't measure it .

Never been over your way but I'm told there's some of the best courses in the country in your area and the best kept secrets. Are you a member?

 

[Migmac]

It's the nearest that wins at the end of the day not how it was measured

our club brought out a rule that a hole in one wouldn't win because you couldn't measure it .

Never been over your way but I'm told there's some of the best courses in the country in your area and the best kept secrets. Are you a member?

I’m a member at Machrihanish GC and Dunaverty GC. Not joining the Dunes, don’t like it much. I caddied yesterday for a group of Canadians, they played the Dunes on Thursday. Said it was terrible. Get yourself over and I’ll treat you to a round on the MGC

 

[Alan Reynolds]

Always fun on the lathe using a metric Vernier and imperial dials on the lathe . keeps the mind active and the scrap rate up.

My old Myford ML7 is Imperial but most of the stuff I’m asked to make is metric. It’s never a problem for me.

 

[Alan Reynolds]

I can but it's never by choice.


Who would rather workout half of 75' 5/16th or 1913mm

No brainer

 

[Alan Reynolds]

37” 13/16ths

 

[R Kraft]

Cities and towns in this part of the world, are far enough apart distance is measured in hours.

 

[Screwdriver]

Cabinet making: nearest 1/64"
Carpentry: nearest 1/16"
Joinery: nearest 1/4"
Shipbuilding: nearest boat

 

[JohnH]

Why do Yanks use lbs instead of tons? Fair enough for your bodyweight or sugar but it gets silly when they start quoting 300,000lbs for something

Seppos use short tons, 2000lbs, so as usual out of step with the rest of the world, who use/used long tons, 2240lbs.

 

[Gareth J]

The beauty of being able to use both metric and imperial is that you can, instantly convey an implication of accuracy easily. Or quickly explain that an object was built/designed in one or the other. It's like, using metric for, in particular, length, there's a missing unit that bridges the very small/accurate to the quite big/high tolerance. We live at this scale. Imperial can be a helpful bridge.

Examples;
A gate, it's 12' wide. It was built in feet and I don't want the implied accuracy of mm or the annoyance of using metres to 2dp. 12' discribes it and its accuracy perfectly.

A 6" nail. It might actually be made to be 150mm but this level of detail isn't really needed. I don't need to choose between 150mm and 155mm nails, if I did, the mm would be a better description. But as it is, 6" is, in my book, more appropriate.

Decimetres might have been a useful intermediate measure but they don't seem to have caught on, which is odd really. They be a good human scale measure.

 

[redlig]

The beauty of being able to use both metric and imperial is that you can, instantly convey an implication of accuracy easily. Or quickly explain that an object was built/designed in one or the other. It's like, using metric for, in particular, length, there's a missing unit that bridges the very small/accurate to the quite big/high tolerance. We live at this scale. Imperial can be a helpful bridge.

Examples;
A gate, it's 12' wide. It was built in feet and I don't want the implied accuracy of mm or the annoyance of using metres to 2dp. 12' discribes it and its accuracy perfectly.

A 6" nail. It might actually be made to be 150mm but this level of detail isn't really needed. I don't need to choose between 150mm and 155mm nails, if I did, the mm would be a better description. But as it is, 6" is, in my book, more appropriate.

Decimetres might have been a useful intermediate measure but they don't seem to have caught on, which is odd really. They be a good human scale measure.

Personally I don't have a problem with mm and inches but do remember the c*ck ups when using 1st and 3rd angle projection. Had a good few laughs when a fabricator sends prototypes up to the Drawing Room made in the wrong projection.

 

[Screwdriver]

There is some merit in using fractional inches for boat building (for example) due to the complexity of multiple similar items gradually tapering or whatever. Something like half this half that, double the other etc.

With the metric system you inevitably end up with fractions of a mm, so you have to either go to the nearest mm or keep track of the rounding errors because at the other end of your boat they're all going to add up!

Example say you want 4 1/4" inch from two planks, that's 2 1/8" each.

The equivalent might be 105mm or 52.5mm each. But now you want to mark the middle and you need to find 26.25mm. I mean really? You're going to build a 10m long boat to 10 microns??

The two obvious issues are 1. you need a calculator and 2. you'll struggle to find a ruler marked in 0.1 of a mm let alone 0.01 without resorting to the sort of metrology we all know and love.

I'm sure there are examples where mm can be said to be superior to fractional inches but I stumbled on a (much better) explanation of why inches were so handy which I could dig out if pressed.

 

[Maker]

Decimetres might have been a useful intermediate measure but they don't seem to have caught on, which is odd really. They be a good human scale measure.

Chemists use cubic decimeters for some reason, its just a long winded way of saying litres.

 

[Screwdriver]

Chemists use Cubic decimeters for some reason, its just a long winded way of saying litres.

A decilitre is a more anthropocentric unit to appreciate. If I said my cup of tea was 2dl water to half a dl milk you would immediately see that's way too milky. But 0.2 litres water to 0.05 litres? A litre is too large a unit not to use decimals to describe and when you enter the realm of decimals there is an implied accuracy which might not be helpful.

Oh, one lump or 0.06kg?

Having said that (I'm in a funny mood this morning), for general building work I do EVERYTHING in mm. I think it's because I design everything in Sketchup, an architectural program and all architects (I believe) use mm. I don't do centimetres. I mean, never....

 

[mtt.tr]

There is some merit in using fractional inches for boat building (for example) due to the complexity of multiple similar items gradually tapering or whatever. Something like half this half that, double the other etc.

With the metric system you inevitably end up with fractions of a mm, so you have to either go to the nearest mm or keep track of the rounding errors because at the other end of your boat they're all going to add up!

Example say you want 4 1/4" inch from two planks, that's 2 1/8" each.

The equivalent might be 105mm or 52.5mm each. But now you want to mark the middle and you need to find 26.25mm. I mean really? You're going to build a 10m long boat to 10 microns??

The two obvious issues are 1. you need a calculator and 2. you'll struggle to find a ruler marked in 0.1 of a mm let alone 0.01 without resorting to the sort of metrology we all know and love.

I'm sure there are examples where mm can be said to be superior to fractional inches but I stumbled on a (much better) explanation of why inches were so handy which I could dig out if pressed.

Though you are correct in what you are saying, thing is you cant work wood that accurately so the error is pretty marginal one wrong move with a plane puts you past that.

 

[Screwdriver]

Though you are correct in what you are saying, thing is you cant work wood that accurately so the error is pretty marginal one wrong move with a plane puts you past that.

IKR but it's the rounding errors that get you when you need to produce a long line of similar measurements. Plus even if you're working to say 1/4", you will need to line up your chisel/knife to a line. Imperial rulers have all the fractionals, do the math for mm and it's easy to slip up and the nearest mm could easily be plus or minus 1mm of error when what you really want is for the end result to be flush.

I read somewhere that your fingertips will easily detect 1-2 thou" step in a smooth surface.