Measurement system - Metric/Imperial?

[gary]

4 hours ago, stelmackr said:

When I lived in England I went to a wood store and pleased to purchase 2" x 4" by the meter and the 2by4's were finished undersized like ours in the US. ;-)

Bob Stelmack

Similar thing happened to me a couple of years ago.  Went to buy 2 x 4s - had to ask for 50x100s (even though they are really 51 x 102) 'cos that's how they size them now.  When they were delivered they were undersized.  Queried that and I was told "...they are CLS".  ?   "Canadian Lumber Standard".  He couldn't explain it but it appears to mean that maximum size is 2x4 and they can be a fair bit smaller.

4 hours ago, TinkerTailor said:

How many hands tall is that horse you got again? He eats how many bushels a week? He sure tears up the first 4 furlongs, but lags the last 4.........

And you can't get a cord of wood now.  Seems the standard sizes are 'Small Trailer', 'Big Trailer' and 'Back of the Lorry Full'.

 

[LumpenDoodle2]

56 minutes ago, gary said:

Similar thing happened to me a couple of years ago.  Went to buy 2 x 4s - had to ask for 50x100s (even though they are really 51 x 102) 'cos that's how they size them now.  When they were delivered they were undersized.  Queried that and I was told "...they are CLS".  ?   "Canadian Lumber Standard".  He couldn't explain it but it appears to mean that maximum size is 2x4 and they can be a fair bit smaller.

And you can't get a cord of wood now.  Seems the standard sizes are 'Small Trailer', 'Big Trailer' and 'Back of the Lorry Full'.

 

Is that 'fell off back of' Lorry Full :-)

[Mattsbagger]

Just started with leather but I have come to embrace the metric system for measuring. It's much more precise for me. Still not sure what a hectare is in relation to an acre though.lol

[HENDREFORGAN]

16 hours ago, stelmackr said:

When I lived in England I went to a wood store and pleased to purchase 2" x 4" by the meter and the 2by4's were finished undersized like ours in the US. ;-)

Bob Stelmack

Oh that's the way it's sold but there is a logic to their sizing madness. 

Timber (lumber) is "rough cut" first to exact sizes and this is where you can buy a nicely accurate "two by four" . . but if you want smooth timber (lumber) then it needs to be planned.  Here in the UK it's then called "planned all round" or "PAR".  They don't take much off, the original cutting is often very accurate, but you will lose between 2mm to 3mm per side . . hence you end up with that smaller size.

Thing is not only is PAR priced to reflect both the cost of the original sized timber and the planning process but most lumber yards will extract the sawdust and then sell that to other customers bagged up . . . that's not nice!  Theft! 

[zuludog]

I think that Liberia and Myanmar (Burma) have now officially adopted the metric system

[Art]

On 10/15/2016 at 5:16 PM, LumpenDoodle2 said:

Is that 'fell off back of' Lorry Full :-)

No darling,

That would be fell off a truck, which means -- stolen while the truck was unattended.

Art

[Art]

On 10/15/2016 at 4:19 PM, gary said:

Similar thing happened to me a couple of years ago.  Went to buy 2 x 4s - had to ask for 50x100s (even though they are really 51 x 102) 'cos that's how they size them now.  When they were delivered they were undersized.  Queried that and I was told "...they are CLS".  ?   "Canadian Lumber Standard".  He couldn't explain it but it appears to mean that maximum size is 2x4 and they can be a fair bit smaller.

And you can't get a cord of wood now.  Seems the standard sizes are 'Small Trailer', 'Big Trailer' and 'Back of the Lorry Full'.

 

People don't want to sell you wood by the cord over here (well at least in Maryland) because it must be stacked at delivery, measure 4' x 4' x 8', and be stacked tight enough that a chipmunk cannot get through it (it's the law).  All they want to do is dump it, sometimes where you want it, and charge you for a "truckload".

Art

[Art]

Don't read this, it is just a midnight xenophobic rant:

 

I guess the old farts like me are hoping that SAE and Imperial measure and sizes will be "What Makes America Great Again".  While I have my wish list out, There should be a law that anything exported from or imported into the U.S. should not have any metric measures, fasteners, or doodads in it, and that all packaging can only have English on the boxes and directions. Malt Whiskey from the Spey or the Island (or any of it for that matter) may have whatever the hell they want to put on it, spelled whatever way they desire, with the requirement that I can tell what it is and that they keep making it.  While I'm at it, if you want to immigrate, legal, illegal, refugee, or otherwise, you will be speaking fluent English in a year or you are on the next boat outta here.   Maybe enough for now.

Now folks, that is what I call Hope and Change!

Art

[Thor]

On 28.9.2016 at 2:56 PM, Dwight said:

...

Same went for screws, . . . the phillips head on a Japanese screw did not mesh with a German screwdriver, . . .  and it was so disconcerting, . . . a lot of us just balked and said forget it.  

Even now, . . . mechanics still have to have two sets of wrenches, . . . 

...

There's a lot of WAS in your post Dwight. I remember grass WAS greener then...

FYI phillips isn't pozidrive. That's like using a phillips on a robertson or pozidrive on a torx. However a phillips can be used on a pozidrive screw well, but not the other way round.

On 16.10.2016 at 0:49 AM, Mattsbagger said:

Just started with leather but I have come to embrace the metric system for measuring. It's much more precise for me. Still not sure what a hectare is in relation to an acre though.lol

10 acre = 4 hectares

BTW even if a country goes metric most structural components are still measured in imperial. For instance all plumbing is measured in inches or the equivalent term of that country. Zoll for Germany. A 5/16 shank equals 8 mm and so on. http://www.hamuniverse.com/antfrac.html

For clarification the leather industry standard worldwide is that areas are measured in square feet. European countries have to convert this into square meter by law. Thickness is measured by mm. Only the US and Canada still trade by ounces. 

That being said, I adapted to inches for leather work as well, cause really nothing in leather crafts has to be so precise that I can't squeeze it a mm or two. Inches is just good enough of a measurement. Not precise, but ok.

Art, you're getting old

 

[HobbledCobbler]

On 9/28/2016 at 3:03 PM, EfrainBG said:

I draw my patterns using inches. It's easier for me to measure, mark and do math in my head with fractions, even though I grew up using the metric system. Also, as someone mentioned above, much of the hardware used is described using imperial units. It makes more sense to me to stick to one system to work out aspect ratios or scale up or down when drawing than to convert back and forth between systems.
 

LOL! Converting back and forth can get you into trouble!

There was an online tutorial from the UK for developing a custom bra pattern. I had to buy a flexible ruler in Metric to draft the pattern because that's what the entire tutorial was done in.

I very carefully measured myself with my Imperial tape measure. Converted those measurements to metric and went on to follow the instructions for drafting the entire pattern in metric.

I finished the first time and thought, "I must have made a huge mistake" and started from the very beginning all over again.

I redrafted the entire thing and ended up with a pattern that was literally big enough for a milk cow!

Will never make that mistake again!

I never did get a pattern for that to work. I finally had to buy one.

[LumpenDoodle2]

.   The dangers of converting measurements, I know them well.   Well done for tackling a bra pattern, makes building the Forth Rail Bridge look like child's play.

[Nuttish]

Get yourself a Harbor Freight fractional/mm or better electronic calipers and both metric and imperial steel rules, and never think about it again. I say two rules because I at least personally find it confusing not to be able to flip and rotate a ruler to get the scale I want without having to also look at a completely different measuring system.

If you get really obsessive about accurately converting between metric and imperial, which is overkill, get yourself a machinist's rule with inches in 10ths and 100ths.

[EfrainBG]

On 25/10/2016 at 3:42 PM, HobbledCobbler said:

LOL! Converting back and forth can get you into trouble!

There was an online tutorial from the UK for developing a custom bra pattern. I had to buy a flexible ruler in Metric to draft the pattern because that's what the entire tutorial was done in.

I very carefully measured myself with my Imperial tape measure. Converted those measurements to metric and went on to follow the instructions for drafting the entire pattern in metric.

I finished the first time and thought, "I must have made a huge mistake" and started from the very beginning all over again.

I redrafted the entire thing and ended up with a pattern that was literally big enough for a milk cow!

Will never make that mistake again!

I never did get a pattern for that to work. I finally had to buy one.

I wish someone had caught me on tape... I literally spit my coffee on the cow part...

Now, back on subject. I'm designing right now a laptop bag/briefcase for the Mrs. Since I always ended up mith either stitches that were too long or too short, I decide I would start marking the stitches in the middle of the bag and work my way out... on the pattern!! That way I would see which stitch was the closest one to the projected size and "round up"... I'm having a breeze assembling this thing together!!!

[HobbledCobbler]

2 hours ago, EfrainBG said:

I wish someone had caught me on tape... I literally spit my coffee on the cow part...

Now, back on subject. I'm designing right now a laptop bag/briefcase for the Mrs. Since I always ended up mith either stitches that were too long or too short, I decide I would start marking the stitches in the middle of the bag and work my way out... on the pattern!! That way I would see which stitch was the closest one to the projected size and "round up"... I'm having a breeze assembling this thing together!!!

I'm sorry! What a waste of good coffee!

Didn't ruin it I hope!

I think that's a good idea with starting in the middle.

I tried hand stitching a pair of mocs. Wow, did it turn out wrong! After the 3rd time I decided to put it aside for later and haven't picked it back up. That's part of the reason I decided to get a leather patcher. Hand sewing is hard enough without messing it up so many times, taking all of the stitching out and doing it again and again and again!

[Art]

On 10/25/2016 at 4:56 PM, LumpenDoodle2 said:

.   The dangers of converting measurements, I know them well.   Well done for tackling a bra pattern, makes building the Forth Rail Bridge look like child's play.

Ah yes, but they built the Forth Rail Bridge using Imperial measurements.  Then again, they also built the Tay bridge (prior Forth Rail Bridge) using Imperial Measurements too, and we know how THAT turned out.

Art

[LumpenDoodle2]

In the words of McGonagall-

It must have been an awful sight,
To witness in the dusky moonlight,
While the Storm Fiend did laugh, and angry did bray,
Along the Railway Bridge of the Silv’ry Tay,
Oh! ill-fated Bridge of the Silv’ry Tay,
I must now conclude my lay
By telling the world fearlessly without the least dismay,
That your central girders would not have given way,
At least many sensible men do say,
Had they been supported on each side with buttresses,
At least many sensible men confesses,
For the stronger we our houses do build,
The less chance we have of being killed.

Edited November 1, 2016 by LumpenDoodle2

[TinkerTailor]

17 hours ago, Art said:

Ah yes, but they built the Forth Rail Bridge using Imperial measurements.  Then again, they also built the Tay bridge (prior Forth Rail Bridge) using Imperial Measurements too, and we know how THAT turned out.

Art

Metric/imperial had nothing to do with it.

The problem with the Tay bridge was they left the tape measures in their pockets. The major determining factors of the crash were poor fitting bolt holes, casting shift, poor and lack of machining, and impurities in the materials. The foundry both "burnt in" patches in the cast iron parts but also put putty consisting of beeswax and iron filings under the paint. Many of the columns had porosity and impurities in one side from bad casting practices, poor metal and horizontal casting techniques.  In addition they found nuts that held down the columns that had burrs of .05" on them from the poor face machining which would have equated to 10+ inches of movement at the top of the pole. The cross braces had a design which used slots and gibs to put them under tension, many of which came loose the first year and were tightened up by hammering them in or replacing with bigger gibs. The inspector who "fixed" the braces was a mason with little metal experience. This may have forced the bridge into an incorrect, stressed geometry.

In addition, trains would frequently exceed the 25mph limit in one direction and cause oscillations in the bridge. This could not happen the other way due to slope and curve. Their was inconclusive evidence that the train may have derailed just before the accident and hit the bridge, starting a cascade. There was argument as to whether the oscillation or speed caused it.

It was basically determined that if the bridge had been built to the proper material standards with inspection, and was used in the way designed, It would have stood. It was noted that it was under designed compared to other similar earlier bridges and also noted that it was re-designed on the fly to reduce weight and number of columns cause the bedrock ended up being way deeper. The onus went solely on the designer because he was responsible to sign off on all of the materials as well as the design. As such, even when the suppliers hid flaws from him actively, it was his responsibility.

If they only had used ANY measurement system, those people may not have died.

I often wonder if we really learned from our mistakes? We now have good designs poorly made in China, with the bare minimum quality control (if any) to allow things to work and sell.

That is how we end up with thomas the train wooden toys for toddlers with lead based paint in toysauRus.......infant formula and pet food with melamine in it.  And cell phone batteries bringing down airplanes.

 

Edited November 1, 2016 by TinkerTailor