Is it wrong that I want to make a replica and write a user manual for this?


I buy a fair bit of stuff from them, but even if I didn’t, I’d still browse their site for gems such as this.


Oh my, I’m glad I did not catch that particular “old tools” bug yet, this is a beauty!

Yes, for folks who are curious about this sort of thing see:

and the book A Treatise of Mathematical Instruments by John Robertson.

The full title is:

of such
Mathematical Instruments,
as are usually put into a
portable case
Showing some of their uses in
Arithmetic, Architecture, Geometry, Surveying, Trigonometry, Geography, Spherics, Perspective, &c.
An Appendix
The Description and Use of the
Gunners Calipers
The Description and Precepts for the Delineation of
Ship-Guns and Sea Mortars

My current reading is also topical: The Perfectionists: How Precision Engineers Created the Modern World by Simon Winchester — highly recommended.

and c.f., my first project on my Shapeoko 3:


That Perfectionists book was a great read (listen for me). I’ve been trying to get different groups of friends to read it, with some success. It was a pretty big hit at the makerspace with a few people.

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Beauty. Certainly out of patent by now - keep the traditional tools alive!

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that is slick. do it lol

i love me some old solid tools, but o lawd those prices.
exactly why i spend a fair time at swapmeets. gems at penny prices

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I can’t wait to see how you do this binding of steel! :smiley:

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I bought the book! Thank you! I didn’t realize that I have been living, learning and teaching by the book! :smiley:

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That looks pretty interesting; however, what does it calculate? I can’t find a description, but I did go to engineering school in the slide rule days so I want one also. Please let me know when the user manual is ready.

I did pick up a copy of The Perfectionists from my local library (just before it closed).

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Those were exactly the questions I had when I saw it — unfortunately the images don’t match up with any of the plates in Robertson (it does show a pair of gunner’s calipers) — I agree with your suspicion it was an early sort of slide rule — unfortunately, my book on slide rules doesn’t have a section on their history — does anyone know of a good resource for that sort of thing?

Used to be that folks made custom slide (and circular) calculators — but they seem to have completely vanished — I was bumfuzzled that I was the only person in the office at my last design job who knew how to use a proportion wheel. Had to go fetch mine to show my children when reading Diver’s Down: Adventure Beneath Hawaiian Seas to them.