Piston with Connecting Rod Keychain 2026

This is an almost replica of a real piston with a moving connecting rod, scaled down into a simple keychain!

This design went through multiple iterations until the proportions and details felt right… 

The final version keeps the piston and connecting rod strong and safe to their mechanical form, 

while being optimized for 3D printing and daily use as a keychain. finally im satisfied with the results, it works and looks just perfect!

here's a quick look of my attempts

ASSEMBLE

Simply push the small Pin/Screw through the piston and rod hole, until you hear a “Click” 
(it might be feelin kinda tight sometimes depends the printer/print, but don't worry, just push it in with a bit of force and it will go perfectly into spot with no issue! ive tested it many times until the release of this project)

No glue, no tools required. It will never come off or break.

I would really like to hear your opinion on the comments!
Please let me know for anny issues, questions, or project suggestions/upgrades you would like to see!