It would help if there was something to show the scale of the slide rule in the pictures.
Yes. It's about two feet wide.
Coincidentally, there's one for sale on eBay right now.
The largest commercial cylindrical slide rule has a scale length of 24m
11–20 of 48 posts
Re: The largest commercial cylindrical slide rule has a scale length of 24m
#12I love slide rules. The amount of functionality stuffed into such a simple device is beautiful. Also, turning multiplication/division into addition/subtraction with logarithmic scales felt like a genius level hack when I first learned about it, like the fast inverse square. On a mildly related note, does anyone know if it's possible to construct a logarithmic scale from simple tools? A demonstration I've always wante…
Maybe they focus the "old guy" rays I give off, but so do I. I have a small collection of slide rules, all normal sized linear types, which I still am fascinated with. They're all made between the 1940s and 1960s and aren't terribly rare but the care and precision that went into their manufacture is amazing given that they weren't terribly expensive back in the day. I especially like the one's made of bamboo. Not as much precision nor speed as a calculator or computer but always remember that we got to the moon on them.
Re: The largest commercial cylindrical slide rule has a scale length of 24m
#13At the other end of the spectrum: I bought one of these Russian KL-1 pocket-watch slide rules:
https://www.sliderulemuseum.com/Manuals/KL-1_RussianCircular...
(I now need reading glasses to use it- so annoying).
Re: The largest commercial cylindrical slide rule has a scale length of 24m
#14Earlier quoted context omitted.
Sorry, I meant "from scratch" meaning no computers. Pen and paper, compass and straight edge, that kind of thing.
Yes. You can calculate logarithms by hand using pen and paper. Then, you can make divisions using the compass and a straight edge until you have a finely divided ruler and then mark logarithms on that ruler based on what you calculated. After all, the slide rule was invented hundreds of years before the computer.
If you want a base-10 scale, I think you only need to calculate the logarithms of 1/5 and 1/2 by hand, and the rest can be done by scaling those ratios (not to scale):
| 10 | => divide by log10(1/2) : 1
| 5 | 5 | => divide by log10(1/5) : 1
|1| 4 |1| 4 | => divide by log10(1/2) : 1
|1| 2 | 2 |1| 2 | 2 | => divide by log10(1/2) : 1
|1|1|1|1|1|1|1|1|1|1|Re: The largest commercial cylindrical slide rule has a scale length of 24m
#15> The drums of the 24 m analog calculators are of course not 24 m long.
I was disappointed
Re: The largest commercial cylindrical slide rule has a scale length of 24m
#16Earlier quoted context omitted.
Sorry, I meant "from scratch" meaning no computers. Pen and paper, compass and straight edge, that kind of thing.
"Pen and paper, compass and straight edge," Compass and straight edges compute what are called the constructible numbers [1], which have 0, 1, and anything obtainable via addition, subtraction, multiplication, multiplicative inverse, and square roots of positive numbers. These will not allow you to get to logarithms. You can't avoid having to calculate them numerically; from there you may also create approximations t…
OTOH the first log table was computed by taking successive square roots of 10. Then you use the binary expansion of each number on your scale, right? So compass-and-straightedge doesn't seem crazy, since square roots are easier that way than numerically by hand.
Re: The largest commercial cylindrical slide rule has a scale length of 24m
#17Earlier quoted context omitted.
You can plot the lines using matplotlib, then print it and stick it on a piece of wood. There are also slide rule PDFs online.
Sorry, I meant "from scratch" meaning no computers. Pen and paper, compass and straight edge, that kind of thing.
Use a pantograph?
https://en.wikipedia.org/wiki/Pantograph
Log scale is a linear fractal, self-similar.
Re: The largest commercial cylindrical slide rule has a scale length of 24m
#18I love slide rules. The amount of functionality stuffed into such a simple device is beautiful. Also, turning multiplication/division into addition/subtraction with logarithmic scales felt like a genius level hack when I first learned about it, like the fast inverse square. On a mildly related note, does anyone know if it's possible to construct a logarithmic scale from simple tools? A demonstration I've always wante…
Maybe they focus the "old guy" rays I give off, but so do I. I have a small collection of slide rules, all normal sized linear types, which I still am fascinated with. They're all made between the 1940s and 1960s and aren't terribly rare but the care and precision that went into their manufacture is amazing given that they weren't terribly expensive back in the day. I especially like the one's made of bamboo. Not as…
I also have a small collection. One is one I found in my grandfather's things. It was a small cheap one, but interesting to me was that it was from an era when computers just starting to supplant people (he worked on a room-sized computer who's job was to count carpool inventory for the army.) I also have one I got from an army-surplus store in a flea market that has various aerial photography calculations tools on the back.
Re: The largest commercial cylindrical slide rule has a scale length of 24m
#19Earlier quoted context omitted.
Sorry, I meant "from scratch" meaning no computers. Pen and paper, compass and straight edge, that kind of thing.
Use a pantograph? https://en.wikipedia.org/wiki/Pantograph Log scale is a linear fractal, self-similar.
That would be useful for geometric scales, which I don't believe a logarithmic scale is
Re: The largest commercial cylindrical slide rule has a scale length of 24m
#20> The drums of the 24 m analog calculators are of course not 24 m long. I was disappointed
lol, so was I. a slide rule enthusiast myself I own several linear and circular slide rules. that said, I have come across an 8foot x 18inches linear slide rule used for teaching but a 45 meter drum shaped slide rule would be awesome.