And I'm very glad, our colleague, Nat, pitched in here.  He's just provided that kind 
of "ammunition" I was talking about.  If one puts his/her mind to the job one *can* 
come up with rational approaches that would work satisfactorily.  Perhaps what one 
needs is, *again I repeat*, just rethink the methodologies used in the field to 
incorporate "hard metric rationalization" approaches, *in spite of ifp components*.  
This should certainly go a long way to mitigate these problems and complaints (which I 
consider not to be illegitimate, mind you, but only blown out-of-proportion) from the 
field.

Marcus

On Sat, 4 Nov 2000 09:38:32    Nat Hager III wrote:
>Let me add my $.02 here.
>
>I don't use either a metric-only or wombat-only tape measure around the
>house since, for practicality reasons, all my tape measures are dual.  When
>I do a home construction project, anything involving a repetitive spacing
>(such as stud spacing, fencepost spacing, etc) is done in wombat, everything
>else is done in metric.  What that amounts to is the job is initially layed
>out wombat, with everything is fine-tuned to fit millimeters. I put in a
>privacy fence last spring, with the fenceposts 8 ft apart, the picket-tops
>90-100 mm above the tops of the posts, and each section centered ~45 mm
>across the post.  It's just more convenient than working with halves,
>quarters, eights, etc.
>
>I have no problem working between inches and millimeters, since I view an
>inch as nothing more than a slightly-miscalculated 25 mm module. I don't
>even mind an inch ruler (though its 1.6% too long!) except that the
>graduations are divided into those weird 16's and 32's rather than a
>convenient 25.
>
>This is just what works for me. I've been working between the two systems
>for years.
>
>Nat
>
>> -----Original Message-----
>> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On
>> Behalf Of Dennis Brownridge
>> Sent: Friday, 2000 November 3 18.57
>> To: U.S. Metric Association
>> Subject: [USMA:8983] RE: building precision
>>
>>
>> Marcus, I'm a diehard metric nerd. I use SI exclusively in all my classes
>> and writings, and proselytize it to the point of obnoxiousness. But I have
>> to tell you that, when I do building, I put away my metric tape
>> and get out
>> my wombat tape because its easier, MUCH MUCH EASIER, given the fact that
>> absolutely no metric building materials are available here. Construction
>> workers are not metric ideologues. They want to get the job done as
>> efficiently as possible, make some money, and go home.
>> Let me explain one more time. If you are still not convinced, I can only
>> suggest you go out and build your own  building with all-wombat parts.
>>
>> I think most people on this list are used to working with small and/or
>> precise things. But we need to understand that most people deal with big
>> and/or imprecise things. There is no NEED or DESIRE to build buildings to
>> millimeter precision. A perfect and smooth building is an UGLY building.
>> Concrete block, stucco, tile, and exterior woodwork are SUPPOSED
>> to be rough
>> and imperfect. In fact, people pay extra to to make them rougher!
>>
>> Concrete blocks and manufactured and laid to a precision of several
>> millimeters (but not 1 mm). The spacings, like all modular spacings, are
>> whole inches. While the location of a single block can vary several
>> millimeters, the AVERAGE spacing must be very precise, because
>> even a small,
>> CONSISTENT error (such as results from rounding off a soft-metric
>> conversion), when multiplied by 100 blocks, becomes a big error. Is that
>> clear?
>>
>> > -----Original Message-----
>> > From: Ma Be
>> > >
>> > On Thu, 2 Nov 2000 11:10:35    Dennis Brownridge wrote:
>> > >Greg and Karl are correct--virtually nothing in building is
>> > measured on the
>> > >job to millimeter precision... That's a waste of time...
>> >
>> > I think that we've finally come to some agreement here, Dennis!
>> > :-)  However, I sort of dispute a little your sentence below.
>> >
>> > >Buildings CANNOT be designed, measured, or constructed to millimeter
>> > >precision. Many of the components (block, brick, dimension
>> > lumber) are not
>> > >even manufactured to millimeter precision (although plywood is).
>> >
>> > If this is the current state of the industry, fine.  But it seems
>> > possible to "push the limits" when it comes to tolerances, so if
>> > one *really* insisted on it I think it *could* be done.  Now,
>> > whether that was necessary is a different story...  ;-)
>> >
>> >  The
>> > >dimensions on wombat architectural drawings are all whole inches...
>> >
>> > Perhaps in the US, but certainly not up here!  I've seen quite a
>> > few such drawings with fractions of inches in them.
>> >
>> > ...So drawing dimensions to the millimeter are about 25
>> > >times more precise than needed. It is false precision, because the last
>> > >digit is incorrect, whereas on an inch-foot drawing all digits are
>> > >significant...
>> >
>> > Very well, then.  If this is the case, Dennis, please explain to
>> > us why you claim the sentence below.
>> >
>> > >HOWEVER, when building a soft-metric building with inch-foot
>> > parts, you DO
>> > >have to bother with extreme precision... Otherwise, the error
>> > would accumulate and
>> > >the parts wouldn't fit.
>> >
>> > ???  But why would this happen with building it in metric and
>> > would not happen in the ifp building itself???  You hinted above
>> > that these parts (blocks, bricks...) are NOT manufactured to
>> > better precision than the inch!!!  Do you see the inconsistency
>> > here, my friend?...
>> >
>> > If a part does not offer a certain precision whether you're doing
>> > things in one scale or the other doesn't matter!  You would end
>> > up with tolerance difficulties, sir!!!
>> >
>> > ...  Therefore, the "trick" to address that is always in
>> > adjusting other things, like the amount of mortar, for instance.
>> >
>> > Therefore, please don't blame the values in metric for the
>> > "mishap" or try to convince us that we would necessarily need to
>> > work with "sub-millimeter" precision!
>> >
>> > >Your blocks would be noticeably out of whack with each other and
>> > with other
>> > >parts of the building. This is why builders are so unhappy about
>> > >soft-metrication. It's a big headache for them.
>> > >...
>> > Granted, there could be challanges.  But I dispute they'd be
>> > insurmountable to the point of abandoning the whole effort
>> > altogether.  As I indicated earlier since it's undeniable that
>> > even in metric construction one can still "work" with "ifp"
>> > components why wouldn't this be true in this case (i.e. when the
>> > system that is rational is metric and one tries to use "rational"
>> > ifp components - true, let's put aside the (also) undeniable fact
>> > that this is one of the very advantages of using the SI system,
>> > and also the wastage aspect which I already acknowledged)???
>> >
>> > Therefore, I can only consider that this is a very lame excuse.
>> > Granted that the comparison is not entirely fair as there are
>> > much, much fewer ifp components in metric construction than the
>> > other way around.  But then again, if this is the case it would
>> > mean it would be time to start pushing suppliers to come up with
>> > more "metrically rational" components, would it not (or in better
>> > precision than they are now)???
>> >
>> > Marcus
>> >
>> >
>> > Angelfire for your free web-based e-mail. http://www.angelfire.com
>> >
>> >
>>
>>
>>
>
>


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