Cover the Red Dot Puzzle

This carnival game is a puzzle that looks easy to play. The person running the game would demonstrate how to cover the red spot using 5 metal disks so no red was showing and then invite customers to play for the chance to win a stuffed animal.

The game requires skill and luck as usually the disks need to be dropped on to red circle from an inch or two above and needed to be placed in a way to leave no red showing. The game is not played at carnivals as much as it used to be, maybe because the solution is available on You Tube.

This project shows how to make the game. This involves making 5 metal disks from aluminum beverage cans and painting a red disk of the correct size.

• 8 empty aluminum beverage cans
• Contact adhesive
• Cardboard
• Red paint

Make some aluminum sheet from a beverage can:

• Cut off the top and bottom of the can using a box cutting knife and a pair of scissors.
• Trim the edges with scissors.
• Cut down the tube and flatten by rubbing against an edge.
• Make seven more sheets from aluminum cans.

• Draw 5 circles on two of the pieces.
• An easy way is to draw around the top of a beverage can.

Spray contact adhesive on one of the sides of all the aluminum sheets and wait until the glue has dried to the touch.

• Laminate three sheets to one with the drawn circles using contact adhesive.
• Repeat for the other sheet with the drawn circles - creating a sheet of 4 layers thick.

Cut around the circles from the laminated sheets to make five aluminum disks.

• Draw a circle with a compass on cardboard and test placing the disks using the method found from a you tube search.
• Adjust the size of the circle so the placement of the disks only just covers the inside of the circle, an adjustment of a millimeter or two in diameter can make a big difference.
• Paint the inside of the circle with red paint.
• The metal disks I made were 11.5cm in diameter and they just covered a red circle of 18.4cm diameter.

Have your friends try to cover the red circle with the 5 aluminum disks. They will likely try different ways and maybe even come close but all of the red needs to be covered to win.

Fully covering the red dot with the 5 aluminum disks can be a challenge even when the solution is followed as precision is needed when dropping the disks. Place the first disk on the left, just slightly clear of the center, the next goes above to the right with the bottom edge to the center, the third goes below with its edge meeting at the center the 4th and fifth go as shown above.