When folks started quarantining, chalk art spilled onto driveways and sidewalks to remind us that there’s still beauty and creative people doing what they always do. Now it’s time to strut your stuff and show your neighbors that things are greener on your slab of concrete. [friedpotatoes] has shared their giant sidewalk recipe with the world so you can paint the town red. With chalk.
Name brand sidewalk chalk is expensive considering how easy it is to make. What Big Chalk doesn’t want you to know is that the ingredients are just water, plaster of Paris, and tempera paint; meaning this project should be safe enough for the junior hackers to get some hands-on time. Some folks use food coloring instead of paint, but we know what happens to clothing when kids get their mitts on food coloring. [friedpotatoes] also includes extensive repurposing of recyclables, which is commendable.
The instructions suggest filling potato chip (crisp) tubes through a milk jug funnel to make giant pieces, but you can use any mold you like. If you have a CNC machine, it should be no trouble to make stamp-like pieces of chalk for tagging on the go, or shapes like arrows when you have to direct a miniature parade.
For permanent and precise sidewalk decorations, you can check out a graffiti paint machine and for totally temporary messages there is a water-dispensing writer.
” If you have a CNC machine, it should be no trouble to make stamp-like pieces of chalk for tagging on the go, or shapes like arrows when you have to direct a miniature parade.”
Umm… have you ever used chalk before? You know it’s not like ink, right?
In those cases, chalk spray and stencils are your best friends. I would not mind a cheap option to make chalk spray.
Please note that for (semi) professional chalking of public roads and sidewalks (= any other than childs play, really) you may need permisson of a local authority.
Also beware that tempura paint is not as “washable” as you might think. At least, not all kinds.
Tempura is batter, i think you mean something else.
I made that same mistake in my first draft. I guess I was typing hungry.
Hagoromo chalk
https://gizmodo.com/why-mathematicians-are-hoarding-this-special-type-of-ja-1711008881
Supposedly used a special type of clam shell.
Wow!
That lead me down a rabbit hole, (I stopped at Mersenne primes)!
Thanks!
Thanks for the Hagoromo reference. Having had my chance at some maths seminars in a former life, I sure can connect to that. Quoting from your reference:
“The bigger question, though, is why mathematicians are still clinging to chalk, period. In the 21st century, chalk is still one of the primary tools of mathematicians.”
They do offer a couple of plausible reasons. My take would be: mathematicians, being more intelligent than the rest of the pack are generally just less vulnerable to fads.
Or maybe mathematicians are still just humans, and find the familiar comforting?
Who needs isopropyl alcohol from whiteboard markers, when maths is a natural high?
@Marcel said: “Please note that for (semi) professional chalking of public roads and sidewalks (= any other than childs play, really) you may need permisson of a local authority.”
Yeah, in America these days you need permission to write on a sidewalk with chalk, but it’s OK to loot and burn an entire city.
@bbp said: “Tempura is batter, i think you mean something else.”
“Tempera” paint – delicious, just ask any four-year-old.