Replica Slide Rule Scales

In this section I have slide rule scales I've created in PostScript that replicate known slide rules. I had to put this hobby aside for a few years, as I had a lot of things going on. I'm back at it, and should have time to clear a back-log of items I'd started earlier.

Years ago, Ed Chamberlain put a mention in the ISRG yahoo group that he'd like to replicate a set of scales for the Goodchild Slide Rule. He mentioned that Peter Monta had built a set of replica PostScript scales for the Otis King by generating PS files from a C program. I'd not heard of PostScipt before then. So, I offered to take on the project for Ed, and built a generator for that slide rule.

I'm much indebted Ed for getting me started, and to Peter, for I have since then been following his model of generating PostScript .

Since then I have been developing replica slide rule scales on and off mostly for simple fun, and/or desire to have a working model of some hard-to-own example of a rule.

How I do it

Paper slide rule scales are fragile, doubtless having a shorter a life span than devices which have engraved scales. In some of my files, I intended the scales to be 'facsimile', that is, good enough to repair/patch the scales old instruments, or provide for an decently authentic looking replica. Examples of the 'facsimile' approach include the Fuller, Thacher, and ByGrave. Most of them are based from medium resolution photos taken from the internet.

I found it hard to locate antique fonts that are close enough to match the models I was working on. I use a font tool called FontCreator (by Hi-Logic) to build customized fonts for my replica scales.

I publish files in PDF (Portable Document Format) instead of PostScript; That way I don't need to distribute custom fonts, and other don't need to install the programming environment and the fonts to be able to print them.

What I like to work on

I avoid working on linear slide rules, in fact, most modern slide rules. Generated scales are well represented in PostScript and other languages, prepared by far more competent people than I.

I am especially interested in long scale and/or high precision slide rules, which include calculators like the Gilson Atlas, the Omnimetre, and the Nystrom Calculator. I've been interested in rendering interesting calculators that I find in patents. The Hexadecimal Slide rule and the MacDonald Logarithmic Spiral Calculator are examples.

If you have something rare old item you would like done in PostScript form, I may be reached at nwharrison (at) sympatico.ca.

Moreover, if you finding difficulty using any of my files, please do contact me.