Question for you metric people.

[hackberry jake]

I assume people that use the metric system cut their lumber to metric sizes... Do you guys still cut dimensions close to standard? Like instead of saying a 2x4 do you call them 50x100? And for some reason, we round way up. Our 2x4 is actually about 1.5x3.5. Do you guys do that as well?

[Ianab]

Basically yes.

A 4x2" here is a 100x50 mm. For rough sawing we just use 25mm equals an inch, close enough. A dimensioned board would be the metric equivalent of your sizes.

I believe a lot of finished construction timber is actually imported into the states from Europe and certainly some from NZ. It will have been cut to metric sizes that match the old Imperial inches.

Ian

[grweldon]

I'm not sure if I understand...

Are you saying that you would mill a 2x4 (4x2?) to 38 x 88 (88 x 38) [76.2 x 38.1] which is actually 1.5 inces by 3.5 inches?  Sounds like that would be difficult without a computer setworks...

What are the dimensions of the relative equivalent in NZ or any other metric country?

[Ianab]

That's the finished machined size of the dry board. Easy enough to set a 4 head moulder to 38 x 88mm

Sawing would be done oversize to allow for shrinkage and machining, and pretty much all the commercial sawing would be done on a big computerised mill anyway.

On a small scale swing blade or dimension saw, you just set the scale to whatever size you want. 100mm, 88mm, makes no difference to where you set the pointer. You aren't sizing a cant and referencing to from the deck to get an exact number of boards. You start at the top, and work your way down until you have a bottom slab left on the bunks.

We would seldom saw construction lumber anyway, our pine needs to be treated and graded for house construction anyway. The mass produced pine is cheap enough that's it's not really worth it.

NZ only officially changed to Metric in 1976, and my current house was built in 1960, so it was built in feet and inches. Changing to metric just means reading the other side of the ruler. Most of them still have both systems on them.

Ian

[Satamax]

Hi.

Well, in france, we use stick framing too on some buildings. A 2x4 is 50mmx100mm when freshly cut, or even a smidge more, then it gets planed and dried, and you end up with 45mmx95mm, or 1" 3/4x 3" 3/4.

Most of the dimensional is 4m lenghts or 20' 8 inch wide (200mm) or 225mm which would be 9inch aproximately. Thicknesses, 25mm, 35mm, 45mm,50mm, 60mm sometimes,75mm and 100mm from 50mm upwards, you rarely see 8 inch wide boards. In pine, you also see 63x175mm, called bastaings, usualy used for hiden joists. And 60x100 called rafters used for rafters. And i forget, 3x4cm, which are usualy 27mmx37mm once dried, and 4x6cm= 37mmx57mm and 4x8cm= 37mmx77mm. That's the most common sizes in france. And in Italy too. Dunno about northern europe. Uk is the same as you, using board feet etc. While we calculate by cubic sizes. 1 cubic meter or 1000000cm3 is worth 350 euros aproximately in treated pine.  So 0.8 cubic M would be worth 0.x350= 280€, and soo on.

[JustinW_NZ]

I have a little "Cheat Sheet" as I call it stuck to the mill.

Lists the Call size (green sawn) Nominal (dried) and Finished size (Dressed or machined size)
I also have it there for hardwood and softwood, as they are different in shrinkage terms..

So a 2*4 or more acurate a nominal 50mm*100 i would cut green at 56mm by 110 in hardwood (Euc's etc) so once dry and now 50mm by 100mm (or close enuf)  its then feed through the planners to become a 40mm by 83mm or so.
As Ian said - easy to setup a 4 sided planner to spit out whatever * whatever

Ive seen a few variances on this here but the key being as long as its agreed on what the end use is and theres enough 'meat' on the board once dry it can be planed to the right thickness, and with enough there any minor twisting etc gets taken out too..

I personaly just ask the customer what they want the wood sizing to be once dry - or nominal size, then explain i will be oversizing it for a start but dont worrie once dry it should be pretty close.
Most stuff here as Ian said isnt for houseing as such (except flooring) , so lots of siding for sheds or outdoor furniture where it really doesnt have to be anything other than say 50mm or 80mm normally.

Anyway, being of the generation after NZ switched to metric i have a hard time with imperial so i like this talk of 50*100's  8)

Cheers
Justin

[Ga Mtn Man]

We (the States) tried to make the switch back when I was in high school.  It didn't stick.  I guess we're just stubborn that way. :-\  I wish it had taken hold as it really is a much easier system to use.  Just a matter of getting "how long is a cm" into your knoggin. 

[hackberry jake]

It might be easier to use, but two by four sure is easier to say  8)

[JustinW_NZ]

It might be easier to use, but two by four sure is easier to say  8)

I cant dissagree there.
But Bear sounds nice as well, right about till you meet one  ;D

hmm beer... (its getting more summer like around here)  ;)

Cheers
Justin

[Ga Mtn Man]

How do you ask for a 100mm x 50mm? 

[Al_Smith]

We (the States) tried to make the switch back when I was in high school.  It didn't stick.  I guess we're just stubborn that way. :-\   

I think the master plan was to totally switch to metric in the mid 80's ,didn't happen .It did as far as automotive stuff to a certain  degree though .

Kind of comical though regarding the system of which I use every day because of my job .That aside if for example you get on a British mototcycle site or related to engines etc  low and behold if they don't refer to the system of measurements we still use .But thinking about that the Brits gave us miles ,feet,inchs of which are three barley corns to the inch .So evidently old habits die hard even for the metrically inclined . ;D

[Okrafarmer]

I personally like the English system, can't stand metric, but I'm just stubborn. I consider the metric system to be too sterile, too sanitized, too official. They missed a great chance to make them more interchangeable-- they could have made a meter to be 40 inches, and that would have been fine, but no.

I likes my feets and inches.  8)

[Brad_S.]

We (the States) tried to make the switch back when I was in high school.  It didn't stick.  I guess we're just stubborn that way. :-\   

I think the master plan was to totally switch to metric in the mid 80's ,didn't happen .It did as far as automotive stuff to a certain  degree though .

The wind industry is almost exclusively metric. Towers heights are measured in meters, wind speeds are measured in meters per second. After a while, you get used to it and can make approximate conversions in your head fairly accurately.

[Okrafarmer]

When I was in Australia, I got so I could convert most any metric item to English in my head, at least approximately. Even the Celsius to Fahrenheit.  :-\

[hackberry jake]

Any temperature calculation you do needs the temperature converted to rankine or kelvin. Really they make more sense. Start at absolute zero an get rid of the negative stuff.

[Okrafarmer]

Any temperature calculation you do needs the temperature converted to rankine or kelvin. Really they make more sense. Start at absolute zero an get rid of the negative stuff.

In theory, you are right, but I don't know anyone personally (not even WHD) who daily thinks in rankine or kelvin, even if they do know how it works. And I'm not about to start.

[hackberry jake]

Me neither, just sayin

[Brucer]

A Black Bear can be just about any colour (including black ;D). It's the name of the species, not the colour of the bear.

When Canada went metric a 2x4 was officially changed to 38 x89 mm. But we still called it a 2x4 -- that was its name.

Of course after we got half way there the government abandoned the whole idea :(.

I built my house in metric, using metric measuring tools. All the drawings were in millimetres and all the tools measured in millimetres. It was a DanG sight easier than working in feet and inches. One mm is between 1/16" and 1/32" and is accurate enough for general carpentry without having to mess with fractions.

[Ianab]

They missed a great chance to make them more interchangeable-- they could have made a meter to be 40 inches, and that would have been fine, but no.

Defeats the purpose of the Standard Units.

One cubic metre of water just happens to weigh one metric ton and be 1,000 litres. It also ties into time, energy, temperature etc.

It's not a random measurement based on the length of a Roman soldiers sandal or where the "Foot" came from.

Ian

[Okrafarmer]

They missed a great chance to make them more interchangeable-- they could have made a meter to be 40 inches, and that would have been fine, but no.

Defeats the purpose of the Standard Units.

One cubic metre of water just happens to weigh one metric ton and be 1,000 litres. It also ties into time, energy, temperature etc.

It's not a random measurement based on the length of a Roman soldiers sandal or where the "Foot" came from.

Ian

All of it was based off the circumference of the earth, which was thought to be one million meters. They found out afterward that they got it wrong by a significant amount. When this inconvenient truth was exposed, someone suggested simply making a meter 40 inches. Then the metric ton, the liter, and so on, would also have changed slightly. But no, the metric-minded people were adamant, it would stay the way it was.

[sigidi]

WOW!! that is just plain crazy!!! whoever heard of a 4x2 being 89x3what was it? ah yeah 38mm if a customer over here wants timber and say 4x2 I ask if they want 4x2 or they want 100x50 - that's it. You cant go cutting it oversize for it to eventually shrink to some measurement, who says when they are going to use it? and each species shrinks differently and in a species it shrinks differently radial to tangential, so then depending upon the orientation and size of growth rings each individual stick will shrink differently too???? whoa my head hurts... off the saw it is 100x50 or 4x2 depending upon the customers on site request. If/when I'm selling timber an 8x2 is 200x50 simple

[Satamax]

It might be easier to use, but two by four sure is easier to say  8)

How do you ask for a 100mm x 50mm?

Easy.

Five by ten :D Cm that is.

[JustinW_NZ]

sigidi - Ive found its slightly off putting for some of the end customers and most of the folk arnt very troubled as long its all the same.
when they say and think 4*2 they just want 100*50

BUT

if im cutting logs for myself and i know there going to be flooring blanks then I need to cut them call size / dry to nomimal / machine to guage OR im going to either waste a lot of material and/or have the planer guys laugh at me  :( (and i hate waste)

As I like to put it to people are you either after rough sawn / rough use lumber or something that needs to be dimentional and uniform (when dried)
In my view ive found an ounce of education can go a long way to getting invited back  :D

Cheers
Justin

[JustinW_NZ]

cabinet timber chart..



nz timber sizing - i like this one as it has cubic meters for each size http://timbernz.com/dimensions.html

[thecfarm]

Ianab,I had no idea that NZ used foot and inches until 1976. Guess I missed that in metric class. I was in school in the conversion to metric era,about '78-79. I guess it got forgotten about.