3D Printed Jart (aka Lawn Dart)
by makermichael, published
Back in the 1980s there was an outdoor game called Jarts. The object of this game was to get an oversized dart to stick inside a plastic ring a set distance away. It was a fun game but not necessarily the most safe. For this reason, yard darts were banned for sale in the USA in 1988. Original Jarts are hard to find, but now you can print your own.
First off, a little advice - Don't make this if you're a moron. I'm not responsible for anything bad that may happen if you build one of these and decide not to use your brain. Also, please keep them away from anyone who's prone to accidents or injuries. Keep in mind, while Jarts (aka Lawn Darts) is a fun family game, they were banned for a reason - don't let that reason be because of you.
This file was modeled from an original Jart. I tried to get the flight charistics as close as possible to the real thing.
Tools required -
Grinder / Dremel
Powerdrill (optional but makes life easier)
Bill of materials (for 1 dart)
10-24 x 36" threaded rod
3D Printed body / handle
2 - #10 Flat washers
20 - 3/16" x 1 1/4" Fender washers
2 - 10-24 Coarse thread nylon lock nuts
1 - 10-24 Coarse thread cap nut
- Print STL - I used an Ultimaker with .01mm layer height and 25% fill. I found it best to use a raft for stability. Use an Exacto knife to clean up the part once printed.
- Measure threaded rod into 12" sections.
- Thread on nylon lock nuts on either side of the cut line. Cutting might mess up the threads and backing the nuts off will make the threads usable. Chuck the rod into your power drill and hold it with the wrench to make things go faster.
- Cut rod. Held it in a vise using a paper towel to protect the threads.
- Take off any rough edges from the cut side with a grinder or Dremel.
- Thread the first nylon lock nut about 2" up, with the flat side facing the tip of the rod.
- Slide on the body, #10 washer, handle, another #10 washer, then thread on the capnut. Snug up the capnut with a wrench. Loctite might be a good idea too, safety frst!!
- Snug up the nylon locknut to take out the play. The fins should stil be allowed to spin freely.
- Add weights - I found that 20 fender washers was just about right. Feel free to experiment.
- Add the other nylon lock nut and tighten it down so there is no play in the washers.
- There should be about 1.5" of ground penetrating tip exposed. You probably shouldn't sharpen it..
- Go ouside, away from any people, pets, and anything else you care about including your personal safety, and give it a toss. With any luck it lands sticking into the ground and not into your head or body. No go make 4 more so you have a complete set!