Code 100 is 1/10 of 1". So....

[Maletrain]

People who use the metric system here on earth still mix-up mass and weight while using the metric system.  They weigh themselves on spring scales, which tell them the force that their bodies exert on the spring while standing on earth' surface, then tell us their mass in Kgs.  But, their weight actually varies slightly among various regions on earth, although by less than the weight of a big lunch. [About 0.7% between extreme high (the surface of the Arctic Ocean) and extreme low (Mount Nevado Huascarán in Peru). ]

It is still not a trivial thing to keep track of force and mass when working with the moon, which has gravitational force at its surface that is about 1/6 the force at earth's surface.  But wait, there's more: the moon is nowhere near as uniform as the earth.  In fact, it is so non-uniform that the mass concentrations in the moon act much like multiple separate bodies that moon satellites need to orbit around.  Try to orbit too low, and the non-uniformities tend to make the orbits so non-elliptical that they will soon hit the surface - which is why some of our early moon orbiters didn't last as long as desired.

And don't get me started on computer geeks using hexadecimal (or octal in the old days) contractions of the binary numbers that the computers actually use.  Write a base-ambiguous number like 714 and see what the differences are between decimal, octal and hexadecimal. (The answers in decimal are 714, 460 and 1,812.)  So, the computers are already doing conversions for us.

There just isn't any substitute for paying attention to the important details. 

But, the metric system does make for easier calculations.  Of course, if we all had 6 fingers on each hand, then inches and feet would be the way to go.  And 8 fingers on each hand would make hexadecimal really intuitive and make us more compatible with computer binary computation systems.

[Is there a prize for thread drifting?  If so, the post about Mars seems to have the lead in drift distance.]

[ednadolski]

And don't get me started on computer geeks using hexadecimal (or octal in the old days) contractions of the binary numbers that the computers actually use.  Write a base-ambiguous number like 714 and see what the differences are between decimal, octal and hexadecimal. (The answers in decimal are 714, 460 and 1,812.)  So, the computers are already doing conversions for us.

I always thought this was a way cool book, even tho I never really had time to do more than skim it:

https://www.amazon.com/Apollo-Guidance-Computer-Architecture-Operation/dp/1441908765/ref=sr_1_1?crid=1W0H6EP9TV2AH&dchild=1&keywords=apollo+guidance+computer&qid=1595622423&s=books&sprefix=apollo+guidance+%2Caps%2C195&sr=1-1

[Mark5]

So ... who uses code 100 in N and Z scale? 

[bbussey]

I don’t understand the logic of the question. The decimal representation is far easier to work with than outdated “standard” fraction notations. Buy some digital calipers that can measure in both imperial and metric, and stop using fractions if you want accurate measuring.

[wcfn100]

The decimal representation is far easier to work with than outdated “standard” fraction notations.

I can see where it could be easier to work with 1/32" or 1/64" rather than 0.03125" or 0.015625".

Jason

[ednadolski]

So ... who uses code 100 in N and Z scale? 

Anyone who wants to accurately represent prototype 16" or 22" tall rail, respectively 

Ed

[bbussey]

I can see where it could be easier to work with 1/32" or 1/64" rather than 0.03125" or 0.015625".

Even more easy to use shapes cut to metric dimensions.
And regarding the fractions, seriously, .031" and .016" is sufficient enough in scratchbuilding and kitbashing.  If you need smaller precision, switch to metric.  I design digital 3D models in metric, and use Imperial in decimal form along with digital calipers when scratchbuiding/kitbashing mainly because all raw materials here are still in Imperial.

[Maletrain]

I can see where it could be easier to work with 1/32" or 1/64" rather than 0.03125" or 0.015625".

Jason

The problem in N scale is that the difference between 1/32" and 1/64" is equivalent to 2-1/2 scale inches.  A scale inch is less than 1/128".  So, things that get hard to see with the naked eye will become visible to a marco lens when trying to take "realistic" pictures.  So, I think it is easier to work with a caliper than a ruler.  Of course, working to 0.001" is not a lot different than working to 1/1024", to get the same level of precision.  But, who can see 1/1024"?  I guess somebody could make a caliper that had 8 dial revolutions per inch and a dial face that had 128 tick marks, but I have never heard of one. 

Ironically, people add/subtract decimal numbers well, whole or fractions, but have to do "conversions" to add say 1-13/64" to 2-27/32" and then subtract 7/8".  But, the fractions 1/2, 1/4, ... 1/1024 are actually binary values that could be represented as 0.1, 0.01, ... 0.0000000001 in the base-2 system - easy peazy for computers, but still require conversion for the way we humans think.

[wazzou]

[Chris333]

I just type in numbers and press enter.

[MarkInLA]

Guys (and I'd hope, gals), whatever transpired since my OP I want to say thanks, whether or not it helped me or you or someone else..
Today I was in Wikipedia reading about couplers and had no idea how many variations of Janney couplers there are, nor did I understand until now how those weird looking flat faced transit couplers worked..But then ya gotta think how lucky we are to have been born with this deep interest in all things railroad..and to have it as a life long hobby while the unlucky rest of the world is oblivious to most of it..
Well, I guess I shouldn't say they are unlucky. They have their hobbies we have no interest in..It's just that the modeling of trains takes in so many facets in order to make it so; from carpentry, to general electricity to deeper electronics, to geometry (spirals, tangents, elevation), physics (weight v power, tractive effort), painting, scenicing, construction, art work, RR practices, history and RR eras, et al...which makes it the best hobby of them all !!...  M