Lmst

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.

#slideRules #DiY

Cardboard circle with half a paperclip in the centre.

Cardboard and paper circular slide rule, with a paperclip through the centre as an 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

#DiY

Closeup of a homemade circular slide rule showing 2 on the outer D scale above 1 on the inner C scale.

Closeup of a homemade circular slide rule showing 4 on the outer D scale above 2 on the inner C scale.

I tried a prototype of the #CardboardComputer with paper glued onto thick, corrugated box cardbord. It's easy to use, but looks messy.

https://cardboard-computer.org

#slideRules #DiY

A circular slide rule printed out on paper and glued to thick cardboard backing, with a thumbtack as a pivot.

I've switched from a whole bunch of text instructions to pictures and captions on the DiY templates page.

#CardboardComputer #slideRules #DiY

#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.

#slideRules #DiY

A paper circular slide rule pinned to a corkboard. The plastic cursor is over 1.5 on the C scale lined up with 7.5 on the D scale.

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.)

https://cardboard-computer.org

#slideRules #DiY #SVG

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).

https://cardboard-computer.org/advanced.html

#slideRules #DIY

A screenshot of a circular sliderule solving the problem √6,970 =~ 83.5 (the answer is at the top on the D scale, under the cursor).

The #CardboardComputer is looking spiffy with the @creativecommons CC0 Public Domain Mark attached.

https://cardboard-computer.org

#SlideRules #PublicDomain #CreativeCommons

Screenshot of a circular slide rule with D, C, CI, A, and K scales. The slide rule has the title "The Cardboard Computer" above the centre grommit, and the text "cardboard-computer.org" and "No rights reserved" below, with the Creative Commons Public Domain Mark icon.

There is also a detailed guide, including a very short Quick Start for addition and multiplication:

https://cardboard-computer.org/guide.html#quick-start

#CardboardComputer #slideRules

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.)

#slideRules #DiY

First working prototype of the #CardboardComputer, calculating the Answer to Life, the Universe, and Everything.

https://cardboard-computer.org

#slideRules #DouglasAdams

Paper circular slide rule showing the answer 42.

I finished #kentuckyroutezero It looks like a point and click adventure game, but IMO it's more visual novel/narrative game. There aren't any puzzles or tense moments, there are only stories. Sometimes you can co-create those stories by picking a dialogue option, on which the story builds on its continuation, but it applies mostly to the mini stories you can read in the dialogue box. Play this game when you're in the mood for reading, not playing.

#gaming #indiegame #cardboardcomputer