"Particle trails" add zing and excitement to games - you often see sparks and flames blazing behind go karts, swords, people and just about anything that moves in the digital world of video games. Wouldn't it be cool to add a particle trail to a real world object - like a skateboard? This project provides an opportunity to learn about innovation, in particular combining two existing ideas (particle trail + skateboard) to create something interesting. Tinkercad is a great place to turn ideas into reality and I couldn't wait to see sparks shooting off the back of my skateboard, so I logged on and got to work!

Please be aware, there is an element of danger involved and care should be taken during construction and use to minimise the risk of injury. Use appropriate safety equipment!

Supplies

Skateboard
Downloadable Firetail STL for 3D printing
6mm (1/4 inch) threaded rod
2 washers and 2 nuts to suit rod
Elastic band
about 1 metre (3 feet) of strong string or paracord
Two 4mm X 50mm (5/32 X 2 inch) bolts
Screws about 30mm (1 1/4 inches) long
Ferrocerium Flint Rod 12mm X 150mm (15/32 X 6 inches)

Step 1: Print the Firetail Accessory

Print the design at 20% infill. You can scale or tweak it depending on the dimensions of your skateboard or just make your own, using this one as a guide. Hinge hole diameter is 8mm. The hinge system will be stronger if printed vertically. Use a file, chisel or utility knife to get rid of support materials when printing is complete.

Step 2: Perform Test Assembly

Hinge

Cut the threaded rod to the correct length with a bolt cutter or hacksaw. Put a nut and washer on each end and check that the hinge moves freely. If there are any problems simply use a file to create a free moving join. Once you are satisfied that the hinge moves freely, remove the threaded rod.

Rod Holder

The rod holder has been printed separately so that it can be reprinted in case of wear or damage. Drill a couple of holes through the rod holder and the bottom plate of the device to join them together. Check that the bolts are holding the rod holder securely, then remove it from the plate so that you can proceed to installation.

Step 3: Add the Rubber Band and Attach Hinge Device to Skateboard

Thread the rubber band through the hole in the top plate and use a small nail, rivet rod or small piece of metal to secure it. carefully drill holes for the top plate, than screw it (with the rubber band intact) to the skateboard. Line up the bottom plate, insert the steel rod and secure with nuts and washers.

Thread the rubber band through the bottom plate and secure it with a small nail or metal rod to ensure the device remains closed and inactive when not in use. Attach string or paracord to the rod. We started out with string, but ended up using paracord as it's much stronger.

Step 4: Attach the Rod Holder

Cut the Ferrocerium Flint Rod into five lengths of about 15mm (3/4 inch). Use great care as sparks will be produced during the cutting process. Do not cut near flammable objects and wear adequate protection, including safety goggles. Tap the five rod segments into the rod holder and attach it to the bottom plate using the bolts. It should hold the rubber band and pull cord in place.

Step 5: Get Rolling!

When you pull firmly on the cord the device will engage, sending sparks out the back of your skateboard! It produces friction, so it also has a braking effect. The firetail device works best on relatively smooth surfaces and takes a bit of getting used to, so go easy at first!

Ideas should not stay stuck inside your head, so use Tinkercad to make them a reality! I hope you enjoyed this instructable, and I hope you enjoy watching sparks fly off the back of your skateboard!