Giant Sidewalk Chalk

16,255

167

28

Introduction: Giant Sidewalk Chalk

Super-sized sidewalk chalk!

Have you eaten way too many Pringles in quarantine and have a giant bag of plaster laying around? Make some giant sidewalk chalk!

Supplies

Materials:

2+ Pringles cans

Plaster of Paris

Duct tape

Tempera paint (optional, make sure it's washable and non toxic)

Water

Empty milk jug (not pictured)

Tools:

Bucket

Stir stick

Plastic cups (for scooping/measuring)

Cutting device

Can Opener

Step 1: Prep the Pringles Cans

Eat all the Pringles!

Once the cans are empty, use a can opener to remove the bottom of one Pringles can so that it is now a Pringles tube!

Step 2: Make a Mega Can

Attach the two cans together top to top with duct tape so you have one very long can. Connecting them top to top will make it easier to get off at the end. Make sure its sealed really well so plaster won't leak out of the seam. It's easier with a second person to help line up the cans.

Step 3: Make a Wide Mouth Funnel

Cut the top off of a milk jug to create a wide mouth funnel for pouring the plaster into the cans.

Step 4: Mix the Plaster

We mixed roughly 6 plastic cups of plaster powder with about 4-5 cups of water for a good pourable plaster mixture. The exact proportions aren't super important, just make sure that it isn't too dry or too thin, err on the side of it being too dry so you don't have to worry as much about leaks. If you want to make colored chalk add in about a half a plastic cup of tempera paint into the mix before adding the water. Make sure the paint you use is non toxic and washable, so you don't stain the concrete or harm the environment. Paint marketed towards kids usually meets these standards.

Step 5: Fill the Molds

Use the milk jug funnel from earlier to help fill the cans. This is definitely easier with a second set of hands to steady the cans and funnel. Be sure to work fairly quickly as plaster only has a 5-10 minute work period before it starts to cure. Fill it all the way to the top!

Find somewhere to leave them upright for about 20-24 hours to fully cure.

We tried lining the cans with wax paper, but it ended up giving a worse finish and made it harder to demold at the end than just the plain can.

Step 6: Demold Your Giant Chalk!

Start by removing the duct tape from the middle and then tear away the Pringles tubes from the plaster! The cardboard was still a bit damp and made it easy to tear off along the seam of the mega can. The chalk will also still be slightly damp and need another 24 hours or so to fully dry.

Step 7: Draw Something!

Make a giant sidewalk drawing with your new homemade giant chalk!

Super-Size Speed Challenge

First Prize in the
Super-Size Speed Challenge

2 People Made This Project!

Recommendations

  • Teach With Tinkercad Contest

    Teach With Tinkercad Contest
  • Halloween Contest

    Halloween Contest
  • Plywood Contest

    Plywood Contest

28 Comments

0
Mad4400
Mad4400

Question 6 weeks ago

Have you tried making black chalk?
I have not been successful as it always turns to light grey when it sets regardless of the type or quantity of dye, ink or paint I use.

0
friedpotatoes
friedpotatoes

Answer 4 weeks ago

I have not, most of the colors turned fairly pastel so I'd imagine you would need a lot of black pigment to cover the white from the plaster. I wonder if grinding up lump charcoal in a blender could be a cheap way to get a lot of black pigment? If you are able to get it to work let me know! I'd do a spot check to make sure it isn't going to stain the concrete because my guess is that you may need a ratio that is like 4 parts plaster to 1 part pigment to get it dark enough. Starting with a dry pigment and the dry plaster might make mixing the pigment in easier as well.

0
friedpotatoes
friedpotatoes

Reply 4 weeks ago

Thanks for posting this link! I did not know this had been posted there and its really cool to see!!!

I hope the chalk worked well for you and your niece!

1
rburr2
rburr2

2 years ago

Are they likely to break in half easier? Is it possible to add a dowel rod in the middle to make it stronger?

0
friedpotatoes
friedpotatoes

Reply 4 weeks ago

Sorry for the late reply, the longer one did end up breaking after a while, but the issue with a dowel is that as you wear down the chalk the dowel will eventually be exposed and make drawing difficult. Id recommend making shorter pieces instead so there is less leverage, but it was fairly strong as is.

4
RichardBronosky
RichardBronosky

2 years ago

This is great. I clicked it hoping there was an aspect of reusing chalk butts that get left over when my kids get almost finished with sidewalk chalk. But, as an added feature, I could place the chalk butts in the bottom of the can. So, I'm going to try that. I'm also going to try making rainbow/tie-dye chalk. Great idea with the plaster-of-paris! I had no idea. This opens up so many project options.

0
friedpotatoes
friedpotatoes

Reply 2 years ago

The consistency is really close to store bought chalk, I would bet you could either crush up the old ends, or just toss them in the mold and it would work great! There was still some white plaster left when I mixed the blue and it made a nice marbled effect on the sides of the bucket, I bet if you mixed colors separately and then poured them in together it would make some nice effects.

0
friedpotatoes
friedpotatoes

Reply 4 weeks ago

I believe most store bought sidewalk chalk is based on plaster with a pigment added, which is what I based the project on! you can see some marbling in the blue one i did and you totally could do it on purpose with different colors kind of like soap making!

1
Mad4400
Mad4400

Reply 6 weeks ago

I just break up my butts using a rubber mallet and a plastic bag and sprinkle them in a mould as I fill it. I used to just mix them all up but now I only add similar colours to what I am making. That way the chalk will give you some shading or highlights depending on what you put in. I only started making chalks for the neighbours kids during covid lockdowns so they could have more variety than the standard 4 colours they had. But I ended up getting right into myself, spending time drawing with them, laying out roads and paths to ride bikes and scooters. I then moved onto doing cartoon characters such as ninja turtles, my lil pony and some old school hanna barbera stuff. I spend most of one night doing a big halloween scene right out the front of their house so the kids could still get into the "spirit" despite not being able to trick or treat at that time as the youngest had just contracted the virus.

0
friedpotatoes
friedpotatoes

Reply 4 weeks ago

You totally could reuse chalk butts with this! They would probably be ok to use as is and just have chunks of another color, or try dissolving them in a bit of water so they mix into the plaster more easily. Crushing and adding them dry would probably work well too

1
steamcheng
steamcheng

Reply 6 weeks ago

Noticed that! TempEra, not tempUra!

0
friedpotatoes
friedpotatoes

Reply 4 weeks ago

Tempura paint probably would not go well with sushi lol, thanks for catching that!

1
Mackramer
Mackramer

2 years ago

Really great idea! Thanks for sharing

3
lclaiborne
lclaiborne

2 years ago

Nice! I wanted to do a mural all the way down the driveway one weekend, but the chalk is pricey and badly colored. This fixes my problem! 😁 Thanks, excellent!

0
friedpotatoes
friedpotatoes

Reply 2 years ago

Do It! You could probably up the paint content a bit to get more vibrant chalk, but do a small scale test and see if it has issues with staining the concrete or something though first! We didn't have any issues getting it off the sidewalk though with a hose, so it would probably be fine.

1
DianaHM
DianaHM

2 years ago

This is really great!!