Introduction: Chalk-O-Lot, the Mega Sidewalk Bike Chalk Grinder With Street Chalk!

Introducing the "Chalk-O-Lot" - a super-sized sidewalk chalk writer for your bike.

Simple and straightforward to create. You're kids will be decorating the sidewalks in no time.

Parts list.

  1. One 1/4 x 4 inch threaded rod with 2 nuts and washers or you could use a ZipTie for this.
  2. One 36 inch long x 1 inch wide x 1/4 thick Alloy bar from Lowe's or Home Depot.
  3. One Container of Plaster Of Paris.
  4. Water
  5. Tempera or water soluble paint. I chose Red, White and Blue for this project for the 4-of July parade. Your kids will love marking up Main Street in the next parade. (Post some pictures if they do).
  6. Three 3 inch nails.

Recommended Tools.

  1. Drill with 3/8 inch drill bit.
  2. Wrench for the tightening the nut or just use a couple zip ties.
  3. Vise for bending the alloy in to right angles.

Step 1: Step 1: Build the Chalk-O-Lot

Here I'm building a a Chalk-O-Lot for a 20 inch wheeled kid's bike.

  1. Take the 36 inch alloy bar and make a mark at 16 inches and 20 inches
  2. Bend 90 degree angles at the marks using a vise. It will end up looking like a square U. Bend the alloy very slowly.

Step 2: Step 2: Drill Holes

  1. Dry fit everything to the bike so you get an idea of what you are about to do.
  2. Drill 2 holes into the ends of alloy bar about 1/4 inch away from the end. These holes should be large enough to fit over the axle on the bike.
  3. Drill 2 holes for the threaded rod at 11.5 inches from the end of the alloy bar. See picture for clarification. This rod clenches the container so it won't fall out.

Step 3: Step 3: Mix Up the Street Chalk

Mix up your colors that you want using water soluble paint. We made three colors.

  1. Divide the dry plaster into different containers that are disposable.
  2. Mix in water and paint. The plaster directions recommend a 2 to 1 ratio.
  3. Now put the mixtures back into the plaster container however you want. You have about 20 minutes to do so before it starts to set up.
  4. Put 3 nails into the container which will ensure the container doesn't fall out when transporting it around. See the last picture.

Step 4: Step 4: Attach the Plaster Container to the Bike.

  1. Slip the container of plaster into the Chalk-O-Lot.
  2. Put the threaded rod through the holes you made at 11.5 inches and bolt it down.
  3. Put black tape or something over the ends of the threaded rod so no one gets hurt. Safety first.
  4. Now hook the Chalk-O-Lot on to the bike by spreading the arms and slipping the holes in the end of the arms over the axle.
  5. Let everything set for a couple of hours and then remove the bottom and top of the plaster carton to expose the chalk.

Step 5: Step 5: Ride-a-lot With Your Chalk-o-lot

  1. Time to get riding! Mark-a-lot with your Chalk-O-Lot . After the chalk has run out on 1 side just flip it over and use up the rest.

As a bonus, flip the entire block of plaster up to the seat for transportation. Just make sure to tie it to the seat post or else it might fall and break in half or crush something.

Like this idea? Please check out the Bike Contest that this is in and vote! >>>>

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