#sliderules — Public Fediverse posts
Live and recent posts from across the Fediverse tagged #sliderules, aggregated by home.social.
-
We Built It with Slide Rules. Then We Forgot How
https://unmitigatedrisk.com/?p=1227
#HackerNews #WeBuiltItWithSlideRules #SlideRules #HistoryTechInnovation #LostSkills
-
We Built It with Slide Rules. Then We Forgot How
https://unmitigatedrisk.com/?p=1227
#HackerNews #WeBuiltItWithSlideRules #SlideRules #HistoryTechInnovation #LostSkills
-
Hackaday: Sliderule Simulator Teaches You How To Do Calculations The Old Fashioned Way. “Ever wanted to know how engineers made their calculations before digital calculators were on every workbench? [Richard Carpenter] and [Robert Wolf] have just the thing—a sliderule simulator that can teach you how to do a whole bunch of complex calculations the old fashioned way!”
https://rbfirehose.com/2026/02/21/hackaday-sliderule-simulator-teaches-you-how-to-do-calculations-the-old-fashioned-way/ -
Hackaday: Sliderule Simulator Teaches You How To Do Calculations The Old Fashioned Way. “Ever wanted to know how engineers made their calculations before digital calculators were on every workbench? [Richard Carpenter] and [Robert Wolf] have just the thing—a sliderule simulator that can teach you how to do a whole bunch of complex calculations the old fashioned way!”
https://rbfirehose.com/2026/02/21/hackaday-sliderule-simulator-teaches-you-how-to-do-calculations-the-old-fashioned-way/ -
Hackaday: Sliderule Simulator Teaches You How To Do Calculations The Old Fashioned Way. “Ever wanted to know how engineers made their calculations before digital calculators were on every workbench? [Richard Carpenter] and [Robert Wolf] have just the thing—a sliderule simulator that can teach you how to do a whole bunch of complex calculations the old fashioned way!”
https://rbfirehose.com/2026/02/21/hackaday-sliderule-simulator-teaches-you-how-to-do-calculations-the-old-fashioned-way/ -
Hackaday: Sliderule Simulator Teaches You How To Do Calculations The Old Fashioned Way. “Ever wanted to know how engineers made their calculations before digital calculators were on every workbench? [Richard Carpenter] and [Robert Wolf] have just the thing—a sliderule simulator that can teach you how to do a whole bunch of complex calculations the old fashioned way!”
https://rbfirehose.com/2026/02/21/hackaday-sliderule-simulator-teaches-you-how-to-do-calculations-the-old-fashioned-way/ -
Hackaday: Sliderule Simulator Teaches You How To Do Calculations The Old Fashioned Way. “Ever wanted to know how engineers made their calculations before digital calculators were on every workbench? [Richard Carpenter] and [Robert Wolf] have just the thing—a sliderule simulator that can teach you how to do a whole bunch of complex calculations the old fashioned way!”
https://rbfirehose.com/2026/02/21/hackaday-sliderule-simulator-teaches-you-how-to-do-calculations-the-old-fashioned-way/ -
#Accounting, #SlideRules, #penmanship, #shorthand, #typing, #telegraphy, and #carpentry were taught to school children in Burma, well into the 1980s. I think it would be socially beneficial to teach these skills to young American kids, today.
Basic accounting and personal finance are useful skills for adults, and indispensable for college kids wielding credit cards.
The slide rule endows the student with a keener understanding of various functions and, more importantly, always to check one's results, mentally.
Being able to write in a beautiful, cursive script with a fountain pen may now be but a party trick, but it still is an important social skill.
Shorthand offers a massive advantage in note taking. Given that every child learns to type social media posts well before they first learn to speak, proper typing technique should be taught to children, for efficiency, for preventing repetitive stress injuries, etc.
Telegraphy is valuable in aviation: VOR and NDB navigation aids transmit their identifiers in Morse code. And Morse code is still a thing in the amateur radio scene.
Teaching kids basic carpentry, like making a rough table, is of limited utility, but they will never forget that experience of making something out of raw materials.
Above all, these old skills are cool, at least in some circles. And if nothing else, these activities will surely keep them off social media.
-
#Accounting, #SlideRules, #penmanship, #shorthand, #typing, #telegraphy, and #carpentry were taught to school children in Burma, well into the 1980s. I think it would be socially beneficial to teach these skills to young American kids, today.
Basic accounting and personal finance are useful skills for adults, and indispensable for college kids wielding credit cards.
The slide rule endows the student with a keener understanding of various functions and, more importantly, always to check one's results, mentally.
Being able to write in a beautiful, cursive script with a fountain pen may now be but a party trick, but it still is an important social skill.
Shorthand offers a massive advantage in note taking. Given that every child learns to type social media posts well before they first learn to speak, proper typing technique should be taught to children, for efficiency, for preventing repetitive stress injuries, etc.
Telegraphy is valuable in aviation: VOR and NDB navigation aids transmit their identifiers in Morse code. And Morse code is still a thing in the amateur radio scene.
Teaching kids basic carpentry, like making a rough table, is of limited utility, but they will never forget that experience of making something out of raw materials.
Above all, these old skills are cool, at least in some circles. And if nothing else, these activities will surely keep them off social media.
-
And just like that, the last detail of the #CardboardComputer falls into place. I had been using a thumbtack as the axis, which wasn't portable, and I was hesitant about a split-pin (which is something people don't always have lying around).
So today I took a regular paperclip, straightened half of it (just with my fingers), pushed the straight part through from the back, and bent it again.
Voilà ! A nice, tight axis.
-
And just like that, the last detail of the #CardboardComputer falls into place. I had been using a thumbtack as the axis, which wasn't portable, and I was hesitant about a split-pin (which is something people don't always have lying around).
So today I took a regular paperclip, straightened half of it (just with my fingers), pushed the straight part through from the back, and bent it again.
Voilà ! A nice, tight axis.
-
Solving 2×2=4 is the #HelloWorld for any slide rule with the basic D and C scales, including the #CardboardComputer:
Adjust the wheels (or slide) to put 2 above 1
Keeping the alignment, read 4 over 2.
Not so hard, was it? There's a lot of unnecessary mystification around #slideRules, but they're simple tools at heart.
You can also try this with the online simulator at https://cardboard-computer.org
-
Solving 2×2=4 is the #HelloWorld for any slide rule with the basic D and C scales, including the #CardboardComputer:
Adjust the wheels (or slide) to put 2 above 1
Keeping the alignment, read 4 over 2.
Not so hard, was it? There's a lot of unnecessary mystification around #slideRules, but they're simple tools at heart.
You can also try this with the online simulator at https://cardboard-computer.org
-
I tried a prototype of the #CardboardComputer with paper glued onto thick, corrugated box cardbord. It's easy to use, but looks messy.
-
I tried a prototype of the #CardboardComputer with paper glued onto thick, corrugated box cardbord. It's easy to use, but looks messy.
-
I've switched from a whole bunch of text instructions to pictures and captions on the DiY templates page.
-
I've switched from a whole bunch of text instructions to pictures and captions on the DiY templates page.
-
#CardboardComputer prototype no. 2 (advanced version) solving the problem 5×25=75.
I cut the plastic cursor out of some stiff plastic "clamshell" packaging I pulled from the recycling bin.
Lessons from this iteration:
Be more careful drawing the hairline on the cursor next time.
Precise wheel alignment is very important, and I need to cover that more in the DiY instructions.
I'm going to glue these onto cardboard backings.
-
#CardboardComputer prototype no. 2 (advanced version) solving the problem 5×25=75.
I cut the plastic cursor out of some stiff plastic "clamshell" packaging I pulled from the recycling bin.
Lessons from this iteration:
Be more careful drawing the hairline on the cursor next time.
Precise wheel alignment is very important, and I need to cover that more in the DiY instructions.
I'm going to glue these onto cardboard backings.
-
What's a Thursday without more #CardboardComputer news? 🙂
There is now a home page with a virtual version that you can drag around manually to solve problems.
The basic and advanced exercise pages now have help deeplinks directly to the relevant sections in the guide.
(I learned a bit making touch events work with SVG on mobile devices.)
-
What's a Thursday without more #CardboardComputer news? 🙂
There is now a home page with a virtual version that you can drag around manually to solve problems.
The basic and advanced exercise pages now have help deeplinks directly to the relevant sections in the guide.
(I learned a bit making touch events work with SVG on mobile devices.)
-
The #CardboardComputer project by @david_megginson has inspired me to unearth two favorite #SlideRules of mine.
First up: A Pickett LogLog Duplex Decitrig, bought in Chicago on my way out to college in 1964 (along with a copy of Von Vega's Seven Place Logarithms). Made out of magnesium alloy in Eye-Saver Yellow, precisely calculated for the wavelength most easily visible to the eye. The Ferrari of slide rules.
-
The #CardboardComputer project by @david_megginson has inspired me to unearth two favorite #SlideRules of mine.
First up: A Pickett LogLog Duplex Decitrig, bought in Chicago on my way out to college in 1964 (along with a copy of Von Vega's Seven Place Logarithms). Made out of magnesium alloy in Eye-Saver Yellow, precisely calculated for the wavelength most easily visible to the eye. The Ferrari of slide rules.
-
The advanced demo page for the #CardboardComputer now covers all the scales: you can see animated solutions for squares, square roots, cubes, cube roots, circle areas and diameters, and three-factor multiplication (in addition to basic multiplication and division).
-
The advanced demo page for the #CardboardComputer now covers all the scales: you can see animated solutions for squares, square roots, cubes, cube roots, circle areas and diameters, and three-factor multiplication (in addition to basic multiplication and division).
-
The #CardboardComputer is looking spiffy with the @creativecommons CC0 Public Domain Mark attached.
-
The #CardboardComputer is looking spiffy with the @creativecommons CC0 Public Domain Mark attached.
-
There is also a detailed guide, including a very short Quick Start for addition and multiplication:
-
There is also a detailed guide, including a very short Quick Start for addition and multiplication:
-
The printable templates for the #CardboardComputer are available now at
https://cardboard-computer.org/templates.html
(There are also PDFs in A4 and US Letter sizes, in case your browser doesn't print properly.)
-
The printable templates for the #CardboardComputer are available now at
https://cardboard-computer.org/templates.html
(There are also PDFs in A4 and US Letter sizes, in case your browser doesn't print properly.)
-
First working prototype of the #CardboardComputer, calculating the Answer to Life, the Universe, and Everything.
-
First working prototype of the #CardboardComputer, calculating the Answer to Life, the Universe, and Everything.
-
In our second session of the day, we heard from Jørn Hafver who trained an AI in audio recognition right in front of us - so it could tell how loud we were clapping at the end. Ben Ashforth spoke about a journey he went on, inspired by a talk from the last gathering, to visit roads named after every day of the year (details at http://benguin.co.uk/roads). @alisonkiddle talked about the maths behind the games Guess Who and Which One Doesn't Belong, and has a pleasing binary chop device made from card with pins and holes. Phil Ramsen followed up on his talk from three years ago and discussed slide rules and Kolmogorov. Daniel Johnson explored the possibly surprising link between Numberblocks and Polyominoes (https://youtu.be/htnZGHjX8p4?si=YzAXxPP7lT2-_Do5&t=522)- and @Tarim said what we've all been thinking and pointed out some illogical song lyrics - lions don't really live in the mighty jungle, and Kilimanjaro is nowhere near the Serengeti! #mathsjam #maths #ai #travelling #guesswho #wwdb #sliderules #means #averaging #kolmogorov #numberblocks #polyominoes #songs #logic #lyrics
-
In our second session of the day, we heard from Jørn Hafver who trained an AI in audio recognition right in front of us - so it could tell how loud we were clapping at the end. Ben Ashforth spoke about a journey he went on, inspired by a talk from the last gathering, to visit roads named after every day of the year (details at http://benguin.co.uk/roads). @alisonkiddle talked about the maths behind the games Guess Who and Which One Doesn't Belong, and has a pleasing binary chop device made from card with pins and holes. Phil Ramsen followed up on his talk from three years ago and discussed slide rules and Kolmogorov. Daniel Johnson explored the possibly surprising link between Numberblocks and Polyominoes (https://youtu.be/htnZGHjX8p4?si=YzAXxPP7lT2-_Do5&t=522)- and @Tarim said what we've all been thinking and pointed out some illogical song lyrics - lions don't really live in the mighty jungle, and Kilimanjaro is nowhere near the Serengeti! #mathsjam #maths #ai #travelling #guesswho #wwdb #sliderules #means #averaging #kolmogorov #numberblocks #polyominoes #songs #logic #lyrics
-
In our second session of the day, we heard from Jørn Hafver who trained an AI in audio recognition right in front of us - so it could tell how loud we were clapping at the end. Ben Ashforth spoke about a journey he went on, inspired by a talk from the last gathering, to visit roads named after every day of the year (details at http://benguin.co.uk/roads). @alisonkiddle talked about the maths behind the games Guess Who and Which One Doesn't Belong, and has a pleasing binary chop device made from card with pins and holes. Phil Ramsen followed up on his talk from three years ago and discussed slide rules and Kolmogorov. Daniel Johnson explored the possibly surprising link between Numberblocks and Polyominoes (https://youtu.be/htnZGHjX8p4?si=YzAXxPP7lT2-_Do5&t=522)- and @Tarim said what we've all been thinking and pointed out some illogical song lyrics - lions don't really live in the mighty jungle, and Kilimanjaro is nowhere near the Serengeti! #mathsjam #maths #ai #travelling #guesswho #wwdb #sliderules #means #averaging #kolmogorov #numberblocks #polyominoes #songs #logic #lyrics
-
In our second session of the day, we heard from Jørn Hafver who trained an AI in audio recognition right in front of us - so it could tell how loud we were clapping at the end. Ben Ashforth spoke about a journey he went on, inspired by a talk from the last gathering, to visit roads named after every day of the year (details at http://benguin.co.uk/roads). @alisonkiddle talked about the maths behind the games Guess Who and Which One Doesn't Belong, and has a pleasing binary chop device made from card with pins and holes. Phil Ramsen followed up on his talk from three years ago and discussed slide rules and Kolmogorov. Daniel Johnson explored the possibly surprising link between Numberblocks and Polyominoes (https://youtu.be/htnZGHjX8p4?si=YzAXxPP7lT2-_Do5&t=522)- and @Tarim said what we've all been thinking and pointed out some illogical song lyrics - lions don't really live in the mighty jungle, and Kilimanjaro is nowhere near the Serengeti! #mathsjam #maths #ai #travelling #guesswho #wwdb #sliderules #means #averaging #kolmogorov #numberblocks #polyominoes #songs #logic #lyrics