locked Re: Drawing and Maps in the SRHA Archives


Hello all

Such old engineering artifacts are not seen very often and are highly respected for what they represent.  

I just want to point out that aside from its historical significance, this drawing is a strikingly excellent example of engineering mechanical drafting/drawing state-of-the-art practice in the 1940s to late 1970s.  It is a what-if markup of an existing blueprint.  It appears to be all hand drawn (using various drafting instruments such as french curves, possibly customized french curves, large radius compasses, etc.) from tables of survey data.  The person or persons who prepared this document spent many, many hours, more likely many weeks, working to first draw it, then to validate it.  He would be given a design, perhaps at the top level, and would be expected to take it to the detailed level shown.  He would have to have significant operational knowledge of how the rail layout should work to meet a complex set of functional requirements which change over time as rail operations progress. Drawing and validating this layout would require painstaking, meticulous work by hand to fit curves to the survey data and to ensure the fit was highly accurate as to the actual layout.  A senior designer and draftsman, a highly respected engineering professional, would have supervised its preparation, and possibly done much of it himself.  Not to mention this is a blueprint.  The original would have been prepared on a vellum surface (like parchment) or high-grade paper using India ink. Mistakes in that media would be wiped off with an alcohol/water mix or scraped off with a razor blade.  The original would have taken months of work.

Nowadays this would all be generated using computer-based tools.  The curve fitting to match the digital survey data would be generated in a few minutes on a PC-scale computer.  Any misfits would be easily adjusted graphically.  This quick cycle would enable many iterations of what-if drills to optimize the layout to its corresponding requirements.  It would also enable collaborative reviews for approval.  The tabular form would be taken directly from highly accurate digital survey data collected on the ground, possibly supplemented by overhead imagery to include LIDAR to show elevation data.  There is an impressive contrast in engineering productivity over almost 80 years.

Were these proposed changes/additions implemented?


Andrew Ramsay
Berryville VA

On Sat, Apr 3, 2021 at 9:52 PM George Eichelberger <geichelberger@...> wrote:
We don’t post many drawings or maps to the .io group simply because so many are quite large. Here’s one @ 207M fits that category. It’s from file discussing the expansion of Cincinnati Union Terminal in 1943. There are several CUT files in the archives starting with an early plan to build “Cincinnati Union Station”. Something certainly worth of research and a TIES article?



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