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  • #16
    Re: Wood!!!

    Well, I wish I could stop the insanity but the confounded ISO measurements are worming their way into just about everything.

    I finished a major project last year and all the dimensions on the drawings had to be metric. Hilarious. The drafting people took the actual manufacturing tolerances, which are numbers like +/- 0.001 and +/- 0.030 inches, and converted them to millimeters.... so the drawings read +/- 0.03 mm and +/- 0.8 mm, etc. Maybe if folks keep saying that the metric system is simpler, it will become true one day.....

    Not questioning you comment on the compressor biz... actually I'm sure you're exactly right.... but the good news it that I just bought a brand new Ingersoll Rand compressor for the garage. The two pressure guages read in - thank heaven! - psi. And the output is rated in standard cubic feet per minute. The tank.... 60 "gallons"

    Just kidding... the gallon/quart/pint/cup/liq oz thing... well even I, ever the defender of traditional measurements, can find no socially redeeming value in that goofy system.
    Last edited by Andy_M; 12-19-2009, 03:00 AM.

    Comment


    • #17
      Re: Wood!!!

      Well, I can only claim 20 years' experience, so you have me there, but perhaps that is a crucial point.

      My father's generation knew the square root of FA about the Metric system, it simply was not taught at school, and you would struggle to find anything marked in Metric scales.

      By the time I went to school, everything was "bilingual". My own kids major on Metric at school, with a smattering of Imperial measurements (to give it the correct and original title ).

      You state that most people have a "feel" for 145 psi. Slightly more than my compressor is capable of But actually, I disagree with the fundamental assertion. Most Americans, definitely. Many Canadians, some Brits and Aussies too. Aircraft engineers the world over probably too. Everyone else - bars, mbars and Pa.

      My own thoughts are in Imperial, I think to myself "about 4 inches" rather than "about 10cm". Then again, if I have a board that is 35 11/16 inches wide, and I want to cut four dadoes in it such that each are equidistant from the other, and the dadoes are 23/32 wide, it all gets a bit more complicated.

      It was interesting you quoted "100 Btu/hr-ft-degF".

      British Thermal Units (not used in Britain for 20 years, BTW) - tiny arbitrary unit, hence why a modest house heater is hundreds of thousands of BTU (shades of Pascals, no?)
      Hours - yes, fine
      Feet - why not inches or yards or miles? - Because it is arbitrary and makes the numbers look nice.
      Fahrenheit - The crowning jewel of scalar stupidity. Even the guy who invented it got it wrong, 100 was supposed to be body temperature, let alone the 32 degree offset.

      I contend that because YOU are used to working in these schemes, it is more productive to you, and as you say, is quicker to get to the drawing stage for you.

      I counter that the Metric based engineer would have put the calculations in his spreadsheet (Excel doesn't do 1/32nds or smaller, BTW), and have automatically produced a drawing off the printer before you had sharpened your pencil.

      We're clearly on opposite sides here, and I want to keep this jovial, but here's my bottom line:

      Where I have a choice, if I want convenience, I will use Imperial measurements. If I want it accurate, I will use Metric.

      Comment


      • #18
        Re: Wood!!!

        Originally posted by billmoy View Post
        Thirty years ago, as the last country in the world remaining on the Foot, Pound, Second (FPS) measurement system, America flubbed adopting the Metric system.

        The conversion was spread out over a couple of years so consumers and industries fought it tooth and nail. (The women with a 36, 25, 36 figure did not want to become 91, 63, 91 centimeters. Machine tool owners did not want to pay to convert the dials from inches to centimeters).

        If we were on the Metric system, we would not be having these problems.
        I fail to see how this has anything at all to do with standard lumber sizes continuing to be reduced in size. No matter what scale you use to measure the material...inches, millimeters, knotted string...it is thinner than before.

        Comment


        • #19
          Re: Wood!!!

          Yup, that is the issue, less wood for more money.

          Unrelated but just as upsetting was a report on NPR yesterday by a
          reporter who visited China's furniture manufacturing district.

          http://www.npr.org/templates/story/s...ryId=121576791

          Jobs lost in NC @ ~$15/hr went to China at ~$0.70/hr. And get
          this...the lumber comes from North America. That's right, popular
          from Canada and the Northern USA is shipped to China, turned into
          furniture, and shipped right back here to be sold under the Broyhill
          label among other well known brand names.

          Gee, I wonder why we have ~10% unemployment here.

          ---------------
          Light is faster than sound. That's why some people seem really bright until you hear them speak.
          ---------------
          “If I had my life to live over again, I'd be a plumber.” - Albert Einstein
          ---------
          "Its a table saw.... Do you know where your fingers are?"
          ---------
          sigpic http://www.helmetstohardhats.com/

          Comment


          • #20
            Re: Wood!!!

            TomApple,

            I totally agree with you... the shrinking lumber size really has nothing whatsoever to do with metric or imperial or for that matter even cubits. In my humble opinion it is just a matter of an ever increasing trend to skim a little extra profit every so often. I have a house that was built in 1887... that's when a "2 by's" were exactly that! Even after more than 120 years of drying, the structure is closer to 2 inches in thickness than today's cuts.

            AndyM,

            I worked for Ingersoll-Rand's Air Power Division back when it started it's metric program and they had an attendance at some of the ISO industrial meetings. I was the only technical writer/illustrator/tech manual person for that division between 1973 and 1982 and my manager and his boss (the chief engineer) were the principal decision makers for the division at that time. In 1985 I found myself in the Process Gas Division where we later became Dresser-Rand and the "Air" moved to Davidson, NC.

            As I understood it, the original ISO decision for air pressure was kg/cm², but the French were insistant on using the bar. Out of compromise, they settled on the kilo-Pascal or kPa unit of measure.

            We spent years trying to convince the company that it needed to go with the ISO standard, but many American manufacturers simply did not want to supply metric or even dual unit gauges, etc. without I-R picking up the tab directly. Likewise, our machine tools and measuring devices would have all had to be changed in unison. There's simply no way to convert everything within a scheduled time frame without extreme cost and a government mandate. Bottom line, after several years of hashing this back and forth we gave up on the idea.

            I left that division in the mid-80's when it moved south. I continued at Painted Post with the Process Gas division (becoming Dresser-Rand) until my retirement in 2003. There we used whatever the country of destination required. I used to think metric was a challenge, but it's nothing compared to safety labels in Cyrillic. (That's almost as bad as figuring out Home Depot's standards for selecting lumber.)

            CWS

            Comment


            • #21
              Re: Wood!!!

              I vote Andy M. and CW Smith on the payroll.

              Comment


              • #22
                Re: Wood!!!

                Originally posted by Roadster280 View Post
                If I want it accurate, I will use Metric.
                Sorry, but that holds no water whatsover. Accuracy is simply the appropriate tolerance and staying within the tolerance. No matter the measure.
                Last edited by tomapple; 12-19-2009, 09:07 PM.

                Comment


                • #23
                  Re: Wood!!!

                  CWS, now a days dealing with display units is easy. Most test gauges are now digital and the user can change from PSI to mm Hg to PSIA or BAR to whatever with the touch of a button. I can remember carrying a bunch of different range gauges for calibrations. When the digital Heises came out they were great. Dual input and interchangeable modules but very expensive ($ thousands of dollars each).
                  ---------------
                  Light is faster than sound. That's why some people seem really bright until you hear them speak.
                  ---------------
                  “If I had my life to live over again, I'd be a plumber.” - Albert Einstein
                  ---------
                  "Its a table saw.... Do you know where your fingers are?"
                  ---------
                  sigpic http://www.helmetstohardhats.com/

                  Comment


                  • #24
                    Re: Wood!!!

                    Originally posted by Roadster280 View Post
                    Well, I can only claim 20 years' experience, so you have me there, but perhaps that is a crucial point.

                    My father's generation knew the square root of FA about the Metric system, it simply was not taught at school, and you would struggle to find anything marked in Metric scales.

                    By the time I went to school, everything was "bilingual". My own kids major on Metric at school, with a smattering of Imperial measurements (to give it the correct and original title ).

                    You state that most people have a "feel" for 145 psi. Slightly more than my compressor is capable of But actually, I disagree with the fundamental assertion. Most Americans, definitely. Many Canadians, some Brits and Aussies too. Aircraft engineers the world over probably too. Everyone else - bars, mbars and Pa.

                    My own thoughts are in Imperial, I think to myself "about 4 inches" rather than "about 10cm". Then again, if I have a board that is 35 11/16 inches wide, and I want to cut four dadoes in it such that each are equidistant from the other, and the dadoes are 23/32 wide, it all gets a bit more complicated.

                    It was interesting you quoted "100 Btu/hr-ft-degF".

                    British Thermal Units (not used in Britain for 20 years, BTW) - tiny arbitrary unit, hence why a modest house heater is hundreds of thousands of BTU (shades of Pascals, no?)
                    Hours - yes, fine
                    Feet - why not inches or yards or miles? - Because it is arbitrary and makes the numbers look nice.
                    Fahrenheit - The crowning jewel of scalar stupidity. Even the guy who invented it got it wrong, 100 was supposed to be body temperature, let alone the 32 degree offset.

                    I contend that because YOU are used to working in these schemes, it is more productive to you, and as you say, is quicker to get to the drawing stage for you.

                    I counter that the Metric based engineer would have put the calculations in his spreadsheet (Excel doesn't do 1/32nds or smaller, BTW), and have automatically produced a drawing off the printer before you had sharpened your pencil.

                    We're clearly on opposite sides here, and I want to keep this jovial, but here's my bottom line:

                    Where I have a choice, if I want convenience, I will use Imperial measurements. If I want it accurate, I will use Metric.
                    Not to uneccesarily belabor the point - because in fact the question of metric v. FPS units does have nothing to do with the odd wood sizes we're getting - but you have made some really interesting comments that bear further discussion.

                    You seem to have allied fractions with FPS measurements. It is indeed unfortunate that tape measures and most scales are graduated in 16ths and 32nds of an inch, because it does make things a little painful in the workshop. It came about by simply repeated halving of the inch... 1/2, 1/4, 1/8, etc. I suppose this made sense way, way back... but doesn't make a lot of sense today. I don't work in fractions, either on the job or in the shop. No one that I know of in my field, of engineering, irrespective of metric, fps, or ips works in fractions. Architects use fractions on their drawings, but I think that's in deference to the way builders build. Fractions are quite a separate question from the issue of metric v FPS.

                    Personally, I like to use a digital caliper... and my favorite is a machinist's scale graduated in 0.01 inches. That's roughly 2/3 the size of a 64th, and more than adequate fineness of resolution for any woodworking operation. You can get these scales at any machinist's supply. I find a 12 inch scale is very useful, but I've used them up to 36 inches long.

                    Btw, Imperial units *isn't* correct... the correct term is "US Customary Units". The term "Imperial units" means you're including Imperial ounces and Imperial gallons and such... and those are different than US Customary.

                    Your Excel argument....hmmm... are you saying that people working in FPS don't use computers? I was solving field problems numerically way back hen we were using punchcards! In inches! The fact is that the computer has no idea what system of measurement your numbers are in. The computer doesn't care.... computers work in binary. No advantage to things being in tens, so no advantage for metric. And no, I haven't done drawings with a pencil in 20 years... don't make the mistake of thinking that just becasue I don't drink the "metric" koolaid that I'm computer averse or somehow stuck in the past.

                    BTW, my copy of Excel isn't limited to 1/32... you might have a previous version, or possibly you should check your cell formatting. My copy will display fractions to 1/999. Although, once again, that issue has nothing to do with metric v. FPS. You can express inches in decimal numbers or - floating point.

                    Which leads to my next point. There is no advantage of either any system of units over any other in terms of accuracy. Accuracy is determine by the number of significant figures you carry in your calculations. If a tape measure graduated to 16ths isn't good enough... use a caliper. The issue is the tape measure, not the system of units.

                    The Btu is a screwy unit, for sure. But who cares? It has survived all this time because it makes the numbers work out nicely. And that is the entire point!! It's not about accuracy (since no system has an advantage over any other), it's ALL about convenience!

                    Before you rag too much on the Fahrenheit scale, take a look in a chemistry book at the triple point of water. It's not 0 degrees C.

                    It's great that you like the metric system, especially if you feel it's working for you. Lots of people (other misguided souls) have been convinced that a system built on 10s is better than a system built on 12s. I'm just poinitng out - as a fairly experienced user of BOTH systems - that there is more than one way to look at the issue.

                    Comment


                    • #25
                      Re: Wood!!!

                      Originally posted by Andy_M View Post
                      Not to uneccesarily belabor the point - because in fact the question of metric v. FPS units does have nothing to do with the odd wood sizes we're getting - but you have made some really interesting comments that bear further discussion.

                      You seem to have allied fractions with FPS measurements. It is indeed unfortunate that tape measures and most scales are graduated in 16ths and 32nds of an inch, because it does make things a little painful in the workshop. It came about by simply repeated halving of the inch... 1/2, 1/4, 1/8, etc. I suppose this made sense way, way back... but doesn't make a lot of sense today. I don't work in fractions, either on the job or in the shop. No one that I know of in my field, of engineering, irrespective of metric, fps, or ips works in fractions. Architects use fractions on their drawings, but I think that's in deference to the way builders build. Fractions are quite a separate question from the issue of metric v FPS.

                      Personally, I like to use a digital caliper... and my favorite is a machinist's scale graduated in 0.01 inches. That's roughly 2/3 the size of a 64th, and more than adequate fineness of resolution for any woodworking operation. You can get these scales at any machinist's supply. I find a 12 inch scale is very useful, but I've used them up to 36 inches long.

                      Btw, Imperial units *isn't* correct... the correct term is "US Customary Units". The term "Imperial units" means you're including Imperial ounces and Imperial gallons and such... and those are different than US Customary.

                      Your Excel argument....hmmm... are you saying that people working in FPS don't use computers? I was solving field problems numerically way back hen we were using punchcards! In inches! The fact is that the computer has no idea what system of measurement your numbers are in. The computer doesn't care.... computers work in binary. No advantage to things being in tens, so no advantage for metric. And no, I haven't done drawings with a pencil in 20 years... don't make the mistake of thinking that just becasue I don't drink the "metric" koolaid that I'm computer averse or somehow stuck in the past.

                      BTW, my copy of Excel isn't limited to 1/32... you might have a previous version, or possibly you should check your cell formatting. My copy will display fractions to 1/999. Although, once again, that issue has nothing to do with metric v. FPS. You can express inches in decimal numbers or - floating point.

                      Which leads to my next point. There is no advantage of either any system of units over any other in terms of accuracy. Accuracy is determine by the number of significant figures you carry in your calculations. If a tape measure graduated to 16ths isn't good enough... use a caliper. The issue is the tape measure, not the system of units.

                      The Btu is a screwy unit, for sure. But who cares? It has survived all this time because it makes the numbers work out nicely. And that is the entire point!! It's not about accuracy (since no system has an advantage over any other), it's ALL about convenience!

                      Before you rag too much on the Fahrenheit scale, take a look in a chemistry book at the triple point of water. It's not 0 degrees C.

                      It's great that you like the metric system, especially if you feel it's working for you. Lots of people (other misguided souls) have been convinced that a system built on 10s is better than a system built on 12s. I'm just poinitng out - as a fairly experienced user of BOTH systems - that there is more than one way to look at the issue.
                      I agree with regard to the measurement system not having a theoretical bearing on accuracy, they are separate issues. However, the practical application of said theory involves real world tools, and real world dimensions. Division, and subtraction of fractions in particular exposes a higher degree of error than simple decimal arithmetic. I'm no math failure, but it is easier to subtract 0.359 from 2.125 than it is to subtract
                      23/64 from 3 1/8. However, I am forced into the latter because the scales on my RIDGID tools are marked in inches and fractions down to 1/64.

                      What I am saying here is that I am less prone to making errors if the arithmetic is more straightforward. Hence Metric has an intrinsic advantage over Imperial in practical application, when the tools in question allow.

                      As for US Customary units, you may wish to consider where the custom came from. The Imperial system. Ergo it ought to be called the Imperial Deviant System. The correct term in the US may well indeed be "US Customary Units", but that is a somewhat blinkered and parochial view.

                      I was of course gently ribbing you over Excel, I have no doubt that you do indeed use computers in your work. It would be impossible to avoid them in today's business environment.

                      However, some clarity on the fractional capability of Excel. The most recent version is 2008. It will indeed go down to 999ths, but that is no use when the measuring scales on tools are marked to 64ths. Thus in the "keep dividing by 2" system, Excel is limited to 16ths. One could indeed set the the denominator to two or even three digits, but if one were to enter 36 divided by 7, the answer is 5 1/7, which is no use at all practically.

                      Here is a shot of the cell formatting for Excel 2008.

                      Merry Christmas!
                      Attached Files

                      Comment


                      • #26
                        Re: Wood!!!

                        Guys, you again seem to be missing the point. It makes no difference that the rule on your "XYZ" is marked in fractions of an inch. As long as you are transferring fractions of an inch as your unit of measure back and forth from bench to the equipment etc. If it's difficult for you or inaccurate...you are somehow making it that way.

                        Now, if you are using a metric rule to measure at your bench then converting to inches at the tool...that could be problematic. And to speak frankly...would be stupid practice.

                        Now that said, anyone who grew up in the USA that works in high precision making of anything...tool and die work, precision machining etc, etc,...doesn't use a fractional rule anyway. We work in decimals of an inch. And can instantly give you the decimal equivalent of ANY fraction of an inch, and have no problem at a machine marked in fractions of an inch.
                        Last edited by tomapple; 12-20-2009, 09:10 PM.

                        Comment


                        • #27
                          Re: Wood!!!

                          Roadster, I understand your comments on the limitations of fractions in the workshop. I think we can agree, though, that it isn't a metric v. FPS (ooops, Imperial deviant) issue. To wit...take a tool with scale marks down to the 32nd. That's 0.031 inches. Now, if you had the tool in metric, it would be marked in millimeters, no? That's 0.039 inches. There is NO WAY that you are going to go down another factor of 10 on your metric tool - that would put the graduations at 0.004 apart, which the manufacturer couldn't even write on the scale. So I'm afraid that, once again good old deviant archaic POS US Customary has a resolution advantage!

                          Fact is, it really makes no difference. For many cuts the scales on the machines, whether in 32s or mm are perfectly adequate. For cuts requiring better precision, I think all woodworkers generally sneak up on the cut, measuring the actual piece rather than relying on the scale. The better wood butchers among us will plan their cuts so that they get all the relevant cuts without moving the fence... if you're clever enough to maintain your datums this way, it often doesn't matter what the actual dimension is - the parts will fit.

                          Tomapple, you make a good point. Yes, machinists and engineers etc DO instantly know the decimal representations of fractions. But that doesn't always help. For example, a common issue in the woodshop is planing stock until it cleans up. You might have to go a bit thinner than your target, say 0.008 or 0.010 thinner. If the next operation is on a machine with 1/32 scales.... you are going to end up needing to be between the lines. Stuff like this happens (at least to me!) all the time, and this is, I think, the kind of thing that Roadster is talking about. In these cases, as I mentioned above, you shouldn't rely on the fractional machine scales anyway.

                          Phew, beat this to death, no? Btw, I'm making a little cocktail table out of gorgeous bloodwood for a present.... 30 INCHES in diameter!! Happy holidays, friends!
                          Last edited by Andy_M; 12-21-2009, 12:04 AM.

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