
The Largest Commercial Cylindrical Slide Rule Has a Scale Length of 24m - rbanffy
https://cacm.acm.org/blogs/blog-cacm/244935-the-worlds-largest-commercial-cylindrical-slide-rule-has-a-scale-length-of-24m/fulltext
======
barbegal
And you can buy it for just £455 [https://historictech.com/product/large-
daemon-schmid-loga-24...](https://historictech.com/product/large-daemon-
schmid-loga-24m-cylindrical-calculator-c-1915/)

~~~
Zenst
I wonder how much it would cost to make one of those, may not be far of what
that price and that is ignoring the historical value - seems kinda cheap and
if I had the disposable I'd of snapped that up.

~~~
pmiller2
That depends on what you mean by "how much it would cost to make." As far as
materials go, if you wanted a period correct replica, while you probably can't
get actual Bakelite (I'd go with brass, if making it look exactly like the
model isn't a big requirement), the rest of the materials are probably easy
and cheap to get. As a one off, your main cost would be time, and the
necessity of being able to access a decent shop. Using more modern and durable
materials would probably cost more than using basic materials from 100 years
ago, I would guess.

Probably the main constraint is the ability to make precise markings on the
cylinder. I bet you could do that with a fairly simple CNC setup, but it would
probably require some custom programming. All in all, it seems like a well-
equipped personal shop or maker space should have all the tools necessary to
do it. For a single piece, it seems like it's just a matter of time and
ingenuity in developing the manufacturing process. Scaling up production is an
entirely different matter, and who knows what the costs would be at any
significant scale?

------
pmiller2
I have never seen a cylindrical slide rule, but I have seen a gigantic linear
slide rule. The whole instrument itself was probably between 10 and 15 feet
long and about 1.5-2 feet wide. I don't know what the total scale length was,
because I never got to see it up close. It was hanging above the blackboard in
one of my high school math teachers' rooms. I think the effective scale length
might have been rather small, because, IIRC, it was actually a demo instrument
used to show people in math classes how to use a slide rule.

------
kanobo
Looks impressive, I love how serious tools back in the day still had visual
embellishments and interesting interfaces that gave a glimpse of the
inventor's personality.

~~~
pmiller2
Me too. This article, plus the link to a different antique slide rule that's
available for sale in the comments, make me want to own one of these with a
steampunk aesthetic.

