NavList:

Thanks, Tony.  If I was starting from scratch, I would surely take a look at that.  But sometimes the best tool for one to use is the tool he is most familiar with.  Although Corel is today just a pale shadow of the market leader they once were (rather like Nortel and RIM/Blackberry; Canadian tech companies have not all prospered), I have been using Corel Draw for most of the last 20 years, through several revisions.  Corel Draw allows you to drive image creation through Visual Basic code, and VB of course supports all kinds of mathematical functions...which allows you to draw scales with mathematical precision.

Let me give you and others an update on where I am on the Mark 1 Navigator's Slide Rule project.

• Early in 2016, I became consumed with generating scales, creating prototypes made of paper and cardboard, doing sight reduction problems using the Bygrave equations...then revising my prototypes based on what I learned about streamlining the process.  My goal was to be able to perform calculations with as few movements of the slide as possible.
  
• I wrote a complete draft of the user manual for the Mark 1, and as I tried to explain to a hypothetical novice how to use a slide rule, I discovered other sorts of revisions to the design that - so I thought - would make it easier to use.
  
• All this happened in the space of just a few weeks.  I ended up a bit burned out, and needing to rebalance my life.  I needed to earn a living as well as goof around with slide rules and navigation equations.  So I took several months off from the slide rule project.
  
• I have re-initiated development now.  The current task is transforming my design drawings into a file format that a 3D printer can use, and selecting a vendor to do the actual printing for me.  My challenge at present is that there seem to be a vast number of vendors, and evaluating their capabilities is a bit of a challenge.  Most of them do not get involved in printing items like a slide rule...and I have to intuit whether they are capable of the kind of precision I would be looking for.
  
• I am attaching the current draft of the user manual.  I welcome feedback, relating both to substance as well as presentation.

Bob

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