This is a very easy modern marble run at an inexpensive price. It is constructed on your closet door and uses magnet tape to hold PVC pipe to sheet metal so you may change it at any time.
Step 1: Parts
In this instructable, you will need sheet metal to cover your whole closet door (measure first,) wood screws (size depending on your door and for mine it took 42 screws,) bag of PVC pipes (3/4 inch), metal marbles, and magnetic tape. The only tools we need are a drill and scissors.
Step 2: Mounting the Sheet Metal on the Door
In this step, we will mount the sheet metal onto the closet door using the screws. Take the sheet metal and at intervals of approximately 6 inches, drill holes 1/2 inch from the edge of the sheet metal, making sure that your holes will be able to be screw into a flat portion of the closet door. You may have to adjust the holes slightly so that they will be able to connect to the closet door at a flush portion. Drill all the holes to the size of screws that you have bought. Install on closet door.
Step 3: Cutting the Magnet Tape
Now let's cut the magnetic tape. Cut it so the tape is thinner and less wide (otherwise known as hot-dog style) and cut it as long as the PVC piping is. Remove the adhesive and place on the PVC.
Note: Try to make the magnetic tape as long as you can on each piece of PVC so that the magnetic attraction is stronger.
Step 4: Ready to Roll!
Now you're finished! Get creative and add weird shape PVC pipes. Some PVC pipes are made to be for toilets, like the P-trap, but just add magnetic tape and you can make better marble runs. Roll marbles into buckets, add extra pieces of magnetic tape to random things that like paper towel rolls or plastic cups, or just have fun with what you have!
Post your ideas in the comment box below!
Note: After a few months, the adhesive of the magnetic tape may wear out. To solve this problem, use hot glue to attach the magnet on the PVC.