→ Please rate the print profiles - It would help tremendously.

This is a working cannon. It has a spring to shoot cannon balls. Use the hinge to aim precisely. Print as many cannon balls (included) as you need or shoot paper balls, peas, etc. Print it as a toy for your kids, grandkids, or present it to friends as a gift. Some use it to launch cat treats for the cats...

In the base carriage, there are identations to store 2 cannon balls. (Better print two).

Use it as a permanent display on your desk, ready to fidget or defend yourself whenever needed.

Hint: To get all versions as STL, use “Download STL” above.

Start with the “thick plunger” version as requested by fabrizio-the-frog and yume.

Printing

• Print it without supports and as oriented in the STL. (The cannon and front of the carriage should point down towards the print bed.)
• The cannon is fully print-in-place: No assembly required, just remove the cannon from the print bed and fire away! (The hinge and piston might need some initial movement to get going.)
• The cannon is designed for easy printing, so bed adhesion should not be an issue.
• The spring (inside the cannon) is 3D printed, and works well also if you print in PLA. There is a hinge included for aiming. It might need some initial movement to get going.

Models included

• You can select a strong or weak spring (weak one for kids, to make it easier to pull and reduce potential injury). There is also a third “big gun” version, able to shoot 23mm nerf rival ammunition or the included bigger cannon ball.
• For each version, there are three models:
  • The cannon only, you can also print this as initial test for your calibration
  • The cannon without wheels
  • Then cannon with wheels. The wheels dont turn, but look cool. They also print without support material
• There is also a cannon ball included

Additional models 

You find a keychain version with ball holder here.

Added the tiny keychain cannon. It holds one ball securely in place and is still fully functional. In case you can print this version, try also the tiny version!

Added the autoloading cannon remix. It can load two balls and you dont need to prime the cannon anymore before putting the cannon balls in.

I added the “big gun” models (idea from nilson_fx): With those, you can shoot 23mm nerf rival ammunition or the included “big gun” cannon ball.

Videos featuring this model

• Thanks to lostintech to feature this model in his youtube channel!
• Thanks to +Ultra for his TikTok video of the cannon.
• Thanks to MakerTeam for their print video on youtube.

Troubleshooting

In case the hinge is fused (not turning) or the spring doesn't work, try slicing with PrusaSlicer. E.g. Cura seems to have trouble with print-in-place hinges.

Other models

I uploaded a new print-in-place spring-driven model, the slot machine!

See also my other fidget models, e.g. the fidget flaps:

I experimented more with the spring mechanism, and created also a finger trainer from them:

There are more print-in-place models, 

the fidget ring

or the spinning coaster:

Thanks

Thanks to iqless for the picture of his “cannon-only” print, and thanks to MatthewHarles for the “cannon-only" two color print! Thanks to deadhawke for his picture of the black cannon being pulled by hand. Thanks to gerd for his photo of the yellow cannon with yellow/blue cannon balls. Thanks to collisto for the photo of the bling-bling white/golden cannon.

Thanks to nilson_fx to pointing out an issue in the cannon design which might have lead to printing issues. Also he had the idea to do a bigger version.

Thanks to makeshift-meatballs to point out that the “big gun” model was not correctly uploaded.

Thanks to revy2k for his picture of the red Big Gun scaled to 230%, his visual deterrent, alongside a normal cannon.

Thanks to rockzz22 for the picture of the collection of his white and green cannons.

Thanks to matemaciek for his picture of the translucent orange and blue cannons.

Thanks to Chris for his picture of the print bed full of cannons in dark red glitter.

Thanks to aroet for his picture of cannon ball and hand-held cannon mass production.